ESSENTIALS 
uF 
CHEMISTRY 
AND 
TOXICOLOGY 
FO. USE OF STUDENTS IN-MEDICINE 
BY 
Ii. A. WTTTHAUS, A.M., M 
Professor of Chen istry and Physics in the ■ .cvetc 
of New York ; Professor of Chemistry amu 'roxu 
logy in the University of Vermont; Me,. W of 
the Chemical Societies of Paris and, Be" tin; 
Member of the American Chem ical Soc 
Fellow of the American Academy o,‘ 
Medicine; of die Nero York Aca- 
- - demy <f Medicine, etc. 
TWELFTH* EDITION 
YORK 
1 AM WOOD & COMPANY 
1894 Copyright by 
WILLIAM WOOD & COMPANY 
1894 
PRESS OP 
STETTINER, LAMBERT A CO., 
ti, S4 A K6 RE *DE ST., 
NEW YORK. PREFACE TO THE FIRST EDITION. 
This little volume is designed to fill a vacancy 
hitherto left unoccupied by chemical writers. 
Many valuable text-books have appeared with- 
in the past few years; none of these, so far as I 
am aware, are designed for, or adapted to the 
special needs of, the American medical student, 
and all are more or less overburdened with 
descriptions of technical and pharmaceutical 
processes which are of no direct importance to 
the practitioner in medicine. In the following 
pages I have omitted all topics which are not 
“essential” to an understanding of those 
chemical problems which have a direct bearing 
upon the practice of medicine; more atten- 
tion has been directed to the chemistry of 
therapeutics than to that of pharmacy, while 
physiological chemistry, which must now be IV 
PREFACE TO THE FIRST EDITION. 
regarded as one of the most important founda- 
tions of rational medicine, has been treated of 
as fully as the limits of the volume will permit. 
The modern system of notation has been 
adopted, and the principles of the atomic theory 
have been dealt with in such a manner as, it 
is hoped, will- afford the student a firm ground- 
work for future study. 
It has not been my intention to write a manual 
of analytical chemistry, as those already at the 
command of the student leave nothing to be de- 
sired ; I have, therefore, given only such ana- 
lytical processes as the physician may reasonably 
expect to make use of in the course of his daily 
practice. 
Weights and measures are given in the metric 
system, and temperatures in degrees of the Cen- 
tigrade scale. 
New York, Oct., 1878. 
R. A. W. PREFACE TO THE PRESENT 
EDITION. 
In the present edition the part relating to the 
compounds of carbon has been in great part 
rewritten and rearranged to keep pace with the 
advances in organic chemistry, so far as is possible 
in a work of this character. Many of the al- 
kaloids have been removed from the “miscel- 
laneous” class to their proper positions in the 
classification, and brief notice is taken of the 
ptomai'ns and of advances in physiological 
chemistry. 
In this edition, also, the orthography adopted 
by the American Association for the Advance- 
ment of Science has been followed. 
R. A. W. 
New York, Sept. 19, 1894 ESSENTIALS OF CHEMISTRY 
AND 
TOXICOLOGY. 
INTRODUCTION. 
1. How do physical and chemical phenomena 
differ from each other ? 
In the former the composition of the matter 
acted on remains unchanged, while in the latter 
it is altered. Thus, when a cylinder of lime is 
strongly heated it becomes white hot and emits 
light; it is still lime, however, after the action 
of the heat, as it was before. This is a physical 
phenomenon. If now we throw this lime into 
hydrochloric acid it disappears, and, after the 
action has been completed, we find neither lime 
nor hydrochloric acid, but two new substances, 
one a solid, called calcium chlorid, the other a 
liquid—water; both of which differ in their com- 
position from the original substances, which have 
disappeared. This is a chemical phenomenon. 
2. What is chemistry ? 
It is that branch of science which treats of the 
composition of substances, their changes in com- 
position, and the laws governing such changes, 
1 2 
ESSENTIALS OF 
3. How may we classify all matter ? 
Into elements and compounds. 
4. What is an element ? 
A kind of substance which we cannot, by any 
known means, split up into any two or more 
other kinds of substance ; as iron, charcoal, oxy- 
gen. Elements are also called elementary or 
simple substances. 
5. What is a compound ? 
A substance made up of two or more elements 
in definite proportions ; as water, sulfuric acid, 
potash. 
6. How many elements are noic known ? 
Sixty-nine. See Appendix A. 
7. What is an atom ? 
The smallest quantity of an elementary sub- 
stance that can enter into chemical action. 
It is, therefore, improper to speak of an atom 
of a compound substance. 
/ 8. What is a molecule? 
The smallest quantity of any substance that 
can exist in a free state. Molecules nearly al- 
ways contain two or more atoms. In molecules 
of elementary bodies the atoms are of the same 
kind, while in compound substances they are of 
different kinds. The molecule of hydrogen is 
made up of two atoms of hydrogen, while the 
molecule of hydrochloric acid is made up of one 
atom of hydrogen united with one atom of 
chlorin. 
9. State the law of definite proportions. 
The relative weights of elementary substances 
contained in a compound are definite and invari- 
able, e.g., water contains 2 parts by weight of CHEMISTRY AND TOXICOLOGY. 
3 
hydrogen and 16 parts of oxygen, never more 
and never less. 
10. State the law of multiple proportions. 
When two elements unite with each other to 
form more than one compound, the resulting 
compounds contain simple multiple proportions 
of one element as compared with a constant quan- 
tity of the other ; e.g., nitrogen and oxygen unite 
with each other to form five compounds, in 
which, for 28 parts by weight of nitrogen, there 
are contained 16 parts by weight of oxygen, or 
some simple multiple of 16 : 
Nitrogen monoxid contains 28 pt's nitrogen & 16 oxygen. 
“ dioxid “ 28 “ “ 16x2=32 “ 
“ trioxid “ 28 “ “ 16x3=48 “ 
“ tetroxid “ 28 “ “ 16x4=64 “ 
“ pentoxid “ 28 “ “ 16X5=80 “ 
11. What is a compound ? 
A substance made up of two or more elements, 
united with each other in definite proportions. 
The properties of a compound are properties of 
its own and independent of those of the constitu- 
ent elements. Thus, the properties of water are 
entirely different from those of the constituent 
gases, oxygen and hydrogen. 
To separate the telements of a compound a 
chemical decomposition is necessary. . 
12. What is meant by “analysis” and “ synY 
” ? L 
x Analysis is the decomposition of a compound 
into simpler compounds or into elements. 
SynfEesis'lsTEeTormation of compounds from 
elements or from simpler compounds. 4 
ESSENTIALS OF 
13. What is a ‘ ‘ mixture ” ? 
A product obtained by uniting into a more or 
less homogeneous whole two or more substances, 
whether elementary or compound. 
The properties of a mixture are an aggrega- 
tion of the properties of its constituents. 
The substances composing a mixture may fre- 
quently be separated from each other by simple, 
physical means. 
E. g. A mixture of sugar and chalk is sweet; 
the sugar remains soluble in water and may be 
separated from the insoluble chalk by washing 
with water. The chalk and sugar are each capa- 
ble of the same chemical actions while in the 
mixture as when free.# 
14. State the laic of reciprocal proportions. 
The ponderable quantities in which substances 
unite with the same substance express the rela- 
tion, or a simple multiple thereof, in whicirtTiey 
unite with each other. 
E. g. Forty parts of calcium combine with 71 
parts of ohlorin, and 40 parts of calcium combine 
with 16 parts of oxygen, therefore 71 parts of 
chlorin combine with 16 parts of oxygen, or the 
combination occurs in the proportions of some 
simple multiples of 71 and 16. 
15. State the laws of Gay Lussac. 
1. There exists a simple relation between the 
volumes of gases which combine with each other. 
2. There exists a simple relation between the 
sum of the volumes of the constituent gases and 
the volume of the gas formed by their union. 
1 vol. chlorin + 1 vol. hydrogen = 2 vols. hy- 
drochloric acid. CHEMISTRY AND TOXICOLOGY. 
5 
1 vol. oxygen + 2 vols. hydrogen = 2 vols. 
vapor of water. 
1 vol. nitrogen + 3 vols. hydrogen = 2 vols. 
ammonia. 
16. State the law of Avogadro. 
Equal volumes of all gases, \mder like condi- 
tions of temperature and pressure, contain equal 
numbers of molecules^ 
“This is al so" know if as the law of Ampere. 
17. By the preceding laws and the results of ex- 
perimefiTprove that, if th~itorn of hydrogen weighs 
one, that of oxygen weighs sixteen, and that of chlo- 
rin thirty-fire and a half. 
It may be shown by experiment that hydrogen 
combines with chlorin and oxygen in the follow- 
ing proportions by volume: 
1 vol. chlorin 4- 1 vol. hydrogen = 2 vols. 
hydrochloric acid. 
1 vol. oxygen + 2 vols. hydrogen = 2 vols. 
water vapor. 
If equal volumes contain equal numbers of 
molecules, 
1 molecule chlorin + 1 molecule hydrogen =s 
2 molecules hydrochloric acid. 
1 molecule oxygen + 2 molecules hydrogen = 
2 molecules water. 
As each molecule of hydrochloric acid contains 
chlorin and hydrogen, the molecules of chlorin and 
hydrogen must each contain two quantities small- 
er than the molecules, i.e., two atoms. Therefore 
2 atoms chlorin + 2 atoms hydrogen = 2 mole- 
cules hydrochloric acid. 
2 atoms oxygen + 4 atoms hydrogen = 2 
molecules water. 6 
ESSENTIALS OF 
But the relations by weight in which the com- 
binations occur are : 
35.5 chlorin -+• 1 hydrogen = 36.5 hydrochloric 
acid. 
16 oxygen + 2 hydrogen = 18 water. 
Therefore, if one atom of hydrogen weighs 1, 
an atom of chlorin weighs 35.5 and an atom of 
oxygen weighs 16. 
18. What is the atomic weight of an element ? 
The weight of one of its atoms as compared with 
the weight of an atom of hydrogen. Thus, an 
atom of hydrogen weighing 1, an atom of oxy- 
gen weighs 16, an atom of sulfur 32, and an atom 
of chlorin 35.5. This weight is relative and not 
absolute. What the absolute weight of an atom 
of hydrogen may be we do not know. 
19. What is molecular weight ? 
The weight of the molecule of any substance, 
simple or compound, in terms of the weight of 
one atom of hydrogen. Thus, the molecule of 
hydrogen being composed of two atoms of hydro- 
gen, its molecular weight is 2. The molecular 
weight of hydrochloric acid is 36.5, its molecule 
being 36.5 times as heavy as an atom of hydro- 
gen. 
The molecular weight of a substance may also 
be said to be the sum of the weights of the atoms 
composing its molecule. Thus the molecule of 
hydrochloric acid contains one atom of hydrogen, 
weighing 1, and one atom of chlorin, weighing 
35.5, therefore its molecular weight is 36.5. 
20. How is Avogadro's law utilized in the deter- 
mination of molecular weights ? 
The specific gravity of a gas (hydrogen = 1) is CHEMISTRY ANB TOXICOLOGY 
7 
the weight of a given volume of the gas compared 
with the weight of an equal volume of hydrogen. 
It is therefore, under Avogadro’s law, also the 
weight of a molecule of the gas as compared with 
the weight of a molecule of hydrogen ; and as 
the unit of molecular weights is the atom, or half 
molecule of hydrogen, the molecular weight of the 
gas or vapor is its specific gravity (hydrogen = 1) 
multiplied by two. 
21. What is the “ valence ” of an element ? 
The combining power of one of its atoms as 
compared with that of hydrogen. 
Atoms of certain elements, such as chlorin, are 
found to be equal in combining power to those 
of hydrogen, i.e., one atom of chlorin is equal to 
one atom of hydrogen; such elements are said 
to be univalent. Atoms of other elements, as 
oxygen, are found to be equal in combining 
power to two atoms of hydrogen ; these are said 
to be bivalent. So other elements are said to be 
trivalent, quadrivalent, quinquivalent, sexivalent, 
as their atoms are equal in combining power to 
three, four, five, or six atoms of hydrogen. 
The valence of an element is expressed sym- 
bolically thus: ' univalent, " bivalent, trivalent, 
iv quadrivalent, v quinquivalent, and vi sexivalent, 
the sign being'placed over and to the right of the 
symbol of the element, thus : O", Pv. (See Q. 23.) 
Elements are also classified as monads, diads, 
triads, tetrads, pentads, according as their valence 
is equal to one, two, three, four, or five. 
22. What are artiads and perissads ? 
Artiads are elements of even valence ; perissads 
those of uneven valence.* 8 
ESSENTIALS OF 
23. What are chemical symbols ? 
Signs by which the elementary substances are 
expressed in chemical writing. The symbol of 
an element is the first (capital) letter of its Latin 
name, usually followed by one of the small let- 
ters; thus the symbol of hydrogen is H, that of 
chlorin Cl, and that of carbon C. 
24. Does the symbol express a definite or an in- 
definite quantity of the element ? 
A very definite quantity, namely, one atom. 
25. What is a formula ? 
A collection of symbols representing a molecule 
and expressing the number and kinds of atoms of 
which it is constituted; tKusrffCl is'the formula 
of hydrochloric a'Cffl, and expresses that its mole- 
cule is composed of one atom of hydrogen and 
one atom of chlorin; H20 is the formula of water, 
and shows that its molecule is composed of two 
atoms of hydrogen and one atom of oxygen. 
26. What is a chemical equation? 
An expression, by means of symbols, numbers, 
and signs, of a chemical action. The sign + is 
used as the equivalent of the word “and,” and 
the sign — indicates that the substances whose for- 
mulae are placed before it have acted upon each 
other (have “reacted”) to produce .the substances 
whose formulae follow the sign. Thus, the equa- 
tion, 
CaO + 2HC1 = CaCl3 + HaO 
indicates that one molecule, composed of one 
atom of calcium and one atom of oxygen, and 
two molecules, each composed of one atom of 
hydrogen and one atom of chlorin, have acted CHEMISTRY AND TOXICOLOGY. 
9 
upon each other. This action has produced one 
molecule, composed of one atom of calcium and 
two atoms of chlorin, and one molecule, com- 
posed of two atoms of hydrogen and one atom of 
oxygen. 
As matter cannot be lost or created, the same 
number of each kind of atom must occur before 
and after the = sign. 
27. What is an acid? 
(1) It is a compound of an electro negative ele- 
ment or radical with hydrogen, which hydrogen 
it can part with in exchange for an electro positive 
element, without formation of a base. (See Q. 
32.) —. 
(2) It is a compound which evolves water })y 
its action upon pure caustic potash, or soda. 
” 28. What is the basicity of an acid1 
It is the number of replaceable atoms of hy- 
drogen contained in its molgqule. 
“Thus, HNO3 is monobasic, 112S04 is dibasic, 
H3PO4 is tribasic. 
~Volybasic acids are those whose basicity is 
greater than one. 
29. What are hydracids and oxyacids ? 
A hydracid is one containing as 
HOI. Xn oxyacid is one containing oxygen; as 
H2SO4. 
30. What is a salt ? 
It is an acid whose hydrogen has been partially 
or completely replaced by an electro-positmTeTe- 
ment or elements (a metal or metals). (See Q. 33.) 
31. What are haloid salts ; what oxysalts '/ 
A haloid salt is a salt' of a hydracid. An oxy- 
saftdS A Siift oFan oxyacid. 10 
ESSENTIALS OF 
32. What is a base ? 
It is a substance which will react with an acid 
to produce a salt and water. 
33. What is a metal ? 
An element capable of replacing the hydrogen 
of an oxyacid to form a .salt, (See Classification 
of 'Elements,' p. 16.) 
34. How many salts of an univalent metal and a 
monobasic acid can exist ? 
Only one. One "atom of the metal is capable 
of replacing one atom of hydrogen, and the acid 
only contains one atom of "IT capable of being so 
replaced ; e.g., the only possible salt of sodium 
and nitric acid is sodium nitrate, NaN03. 
35. How are the salts of the monobasic acids with 
bivalent metals formed? 
An atom of the bivalent metal displacing two 
atoms of hydrogen, and the monobasic acids only 
containing one atom of replaceable hydrogen in 
each molecule, the formation of salts by these two 
substances is only possible when two molecules 
of the acid combine and the atom of bivalent 
metal replaces their united hydrogen, thus : 
211 NOs + Zn = Zn(N03)» + H2 
Nitric acid 
(2 molecules). 
Zinc. 
Zinc 
nitrate. 
Hydrogen 
univalent. 
36. How many salts may be formed by an univa- 
lent metal and a dibasic acid ? 
Two. One in which only one of the atoms of 
hydrogen has been replaced by an atom of the 
metal, e.g., HNaSO<; and another in which both CHEMISTRY AND TOXICOLOGY. 
11 
atoms of hydrogen have been replaced by ajxums 
of the metal, e.g., Na2S04. 
f 37. What is understood by the reaction of a sub- 
stance ? 
All the acids and some salts have the power of 
reddening certain vegetable blue colors, such as 
solution of litmus ; these are said to have an 
acid reaction. Certain other substances, as the 
hydroxids of sodium and potassium, have the 
power of restoring the blue color of litmus after 
it has been reddened by an acid ; these sub- 
stances are said to be alkalineTn reaction. When 
a substance wITTneither redden litmus nor re- 
store its blue color When reddened, it is said to be 
neutral i 1 " 
38. What is meant by “ neutralization’’’’? 
The addition of an acid to a base (or rice 
versa) in such quantity that they are both 
verted entirely into salt. 
The reaction changes from acid or alkaline to 
neutral, except when the salt formed.itself has 
arTacfd or alkaline reaction. 
39. The formula of hydrochloric acid being HCl 
and that of caustic soda NallO, and the atomic 
weights being: II = 1 ; Cl — 35.5; Na = 23; 
0 — 16, how much caustic soda is required to neu- 
tralize 36.5 parts of hydrochloric acid? and what 
are the formula and quantities of the products? 
The reaction takes place according to the 
equation : 
IIC1 + NallO = NaCl + 11,0 
The molecular weight of hydrochloric acid is 12 
ESSENTIALS OE 
1 -l- 35.5 = 36.5 ; that of caustic soda is 23 + 1 + 
16 = 40. Therefore 40 parts of NaHO are re- 
quired to neutralize 36.5 parts of HC1. The 
products are : NaCl, 23 + 35.5 = 58.5 5 and 
HsO, 2 -t- 16 = 18. As 36.5 + 40 = 76.5 
equals 58.5 + 18 = 76.5, the work is correct. 
(See Q. 489, 490.) 
Note.—The student should be frequently practised in 
writing equations, and should be called upon from time 
to time to make calculations such as the above, and later 
to take into account water of crystallization, purity, 
etc. See Stoichiometry, in Manual, 4th Ed., pp. 44-46. 
40. How are compounds containing two, three, 
or four elements distinguished by name ? 
A compound whose molecule contains two_ele- 
ments is called a binary compound, e.g., HV6 ; 
one containing three"elemehtsis" called a ternary 
compound, e.g., H2S04 ; and one containing 
four elements is called a quaternary compound 
e.g., KHS04. 
41. What is the fundamental principle of mod- 
ern chemical nomenclature ? 
That the name"shall indicate, so far as possi- 
ble, the composition ancTconstitution of the sub- 
stance. 
By 'composition we understand the kinds of 
elements of which the molecule of the com- 
pound is composed, and the number of atoms of 
each kind. By constitution we understand the 
relations which the several atoms constituting 
the molecule bear to each other. (See Q. 692.) 
42. How are the names of binary substances con- 
structed ? 
They are made up of the name of the more CHEMISTRY AND TOXICOLOGY. 
13 
electro positive, followed by the name of the 
more electro-negative, in which the termination 
in, on, ogenf~ygen, orus, turn, or urip changed 
£0 idj e.g., the compound of potassium and 
chlorin is called potassium chlorid ; thiaf'of’cal- 
cium and oxygen,' calcium oxid ; and that of 
sodium andsuliiir, sodium sill fid. 
43. When more than oneHnnary compoj.md of 
the same two elements. exisl, how are they distin- 
gwished by name ? 
By prefixing to either word of the name, con- 
structed as in No. 42, the Greek numeral corre- 
sponding to the number of atoms of the element 
designated by that word, as compared with a 
fixed nnmhev of atoms of the other element: 
N20 = Nitrogen monoxid. 
N0(=N202) = Nitrogen di'oxid. 
N203 = Nitrogen tfnoxid. 
N02(=N204)= Nitrogen tetrox\d. 
N2Os = Nitrogen pentoxid. 
44. How are the names of the oxyacids construct- 
ed? 
By writing the word acid, preceded by the 
name of the electro-negative element other than 
oxygen, in which the termination is modified, 
and to which a prefix is sometimes added to in- 
dicate the degree of oxidation. 
When but two acids exist, that containing the 
least amount of oxygen is designated by the ter- 
mination ous ; that containing the greater amount 
of oxygen, by the termination ic—e.g 
HN02 = Nitres acid. 
HNOs = Nitn'c acid. 14 
ESSENTIALS OF 
When more than two acids are known, that 
containing less oxygen than the ous acid is des- 
ignated by the prefix hypo ; that containing more 
oxygen than the ic acid, by the prefixj>g£—e.g.: 
HC10 = Hvvochloxaus acid. 
HClOa = Ciilo'nw.s acid. 
HC103 = Chlor|OiH3. 
HCIO, = Perchloric acid. 
In the cases of the acids of sulfur and of phos- 
phorus (q. v.), derived acids exist, which are 
differently named. 
45. How are the names of oxy salts derived from 
those of the corresponding acids when the valence of 
the metal equals the basicity of the acid ? 
By prefixing to the name of the acid that of 
the metal, changing the termination oils into ite, 
or ic into ate, and expunging the word acid: 
Nitrous acid. Potassium nitrite. 
UNO, Iv'NOa 
Sulfuric acid. Calcium sulfate. 
H,SO« Ca"S04 
The salts of the hydracids, being binary com- 
pounds, are named in accordance with No. 42 : 
IIC1 KC1 
46. How are the names of oxysalts derived from 
those of the acids when the valence of the metal and 
the basicity of the acid are unequal ? 
In the same way as in No. 45, except that the 
Greek numeral corresponding to the number of 
Hydrochloric acid. Potassium chlor/d. CHEMISTRY AND TOXICOLOGY. 
15 
atoms of the metal in the salt is prefixed to the 
name of the metal, whose termination is also 
changed to ic: 
H3P04 
K'H2P04 
Phosphorte acid. 
Monopot&ssic phosphate. 
K,HPO« 
D/potassic phosphate. 
k3po. 
For rules governing chemical orthography and 
pronunciation, see Manual, Appendix A, pp. 
511-515. 
Trtpotassie phosphate. 16 
ESSENTIALS OF 
CLASSIFICATION OF THE ELE 
MENTS. 
CLASS I. TYPICAL ELEMENTS 
Hydrogen—Oxygen. 
Elements whose oxids combine with water to form 
acids, never to form bases. Which do not displace 
the hydrogen of oxy acids to form oxysalts. 
Group I. Fluorin, chlorin, bromin, iodin. 
Group II. Sulfur, selenium, tellurium. 
Group III. .Nitrogen, phosphorus, arsenic, 
antimony. 
Group IV. Boron. 
Group V. Carbon, silicon. 
Group YI. Vanadium, columbium, tanta- 
lium. 
Group YII. Molybdenum, tungsten, osmi- 
um (?). 
CLASS II. ACIDULOUS ELEMENTS. 
Elements whose oxids unite with water, some to 
form acids, others to form bases. Which form 
oxysalts. 
Group T. Gold. 
Group II. Chromium, manganese, iron. 
CLASS III. AMPHOTERIC ELEMENTS CHEMISTRY AND TOXICOLOGY. 
17 
Group III. Glucinium, aluminium, scandi- 
um, gallium, indium. 
Group IV. Uranium. 
Group V. Lead. 
Group VI. Bismuth. 
Group VII. Titanium, germanium, zirconi- 
um, tin. 
Group VIII. Palladium, platinum. 
Group IX. Rhodium, ruthenium, iridium. 
Elements whose oxids unite with water to form 
bases, never to form acids. Which form oxysalts. 
Group T. Lithium, sodium, potassium, ru- 
bidium, caesium, silver. 
Group II. Thallium. 
Group III. Calcium, strontium, barium. 
Group IV. Magnesium, zinc, cadmium. 
Group V. Nickel, cobalt. 
Group VI. Copper, mercury. 
Group VII. Yttrium, cerium, ytterbium, lan- 
thanium, didymium, erbium, samarium. 
Group VIII. Thorium. 
See Manual, 4th ed., pp. 52-54. 
CLASS IV. BASYLOUS ELEMENTS. 18 
ESSENTIALS OF 
CLASS I. TYPICAL ELEMENTS. 
HYDROGEN. H'. 1. 
47. What are the symbol, valence, atomic and 
molecular weights of hydrogen ? 
Its symbol is H. It is univalent. The weight 
of one atom of hydrogen is the unit of atomic 
weights, the standard with which the atoms are 
compared. Its atomic weight is therefore 1. Its 
molecular weight is 2. 
48. Ilow does II exist in nature ? 
Free in volcanic gases, in lire damp, in me- 
teorites, in the gases exhaled from the lungs, 
ahTHn those of the stomach and intestines. In 
combination, in Water, hydrogen sulfid, am- 
moniacal compounds, and in many organic sub- 
stances. 
4&:~~IIow is it prepared ? 
By the decomposition of water (which is a 
compound of hydrogen and oxygen). Either : 
1. By the action of a galvanic current. 2. By 
certain metals having a great tendency to unite 
with oxygen, as sodium. 3. By the action of 
hot zinc or iron. 4. By the action of these 
metals (zinc or iron) on cold, dilute sulTuric or 
hydrochloric acid. 'ITie last, is t ho method which 
is usually resorted to. When obtained by this 
process, H is’almost always contaminated with 
small quantities of other gases, due to the pre- CHEMISTRY AND TOXICOLOGY. 
19 
sence of impurities in the zinc and acid used. 
When perfectly pure H is required it is better to 
resort to the decomposition of water by the bat- 
tery. See Manual, pp. 55-57. 
50. Write the equation representing the action 
between zinc and sulfuric acid. 
H,S04 + Zn + «H20 = Z11SO4 + 20 + H„ 
Sulfuric 
acid. 
Zinc. 
Water. 
Zinc 
sulfate. 
Water. 
. Hy- 
drogen. 
51. State some of the principal physical proper- 
ties of hydrogen. 
A gas, colorless, odorless, and tasteless. It is 
thenghteSTToiown ‘substance, being about 14£ 
times lighter than air. One litre of hydrogen 
weighs, at 0 ''TTand 760 mm. barometric pres- 
sure, Grm. 0.0896. It is exceedingly diffusible. 
At —140° (—229° Fah.) and 650 atmospheres 
pressure it forms a steel-blue liquid. Its solu- 
bility in water is small, but is the same at all 
temperatures. 
52. What results when a flame is applied to pure 
hydrogen ? 
The gas ignites, and burns with a pale blue 
flame, producing little light, but mucfiTTfeatT' 
The product of the burning is water = JH^O. 
53. Is it a supporter of combustion or Inspira- 
tion ? 
No. A taper introduced into a vessel of H is 
extinguished, the hydrogen itself burning at the 
mouth of the vessel. An animal introduced into 
an atmosphere of pure hydrogen dies, not from 
any active agency of the gas, but from lack of 
oxygen. 20 
ESSENTIALS OF 
54. Explain what takes place when certain 
oxids, as those of iron or copper, are heated in 
hydrogen. 
At elevated temperatures the oxygen lias a 
greater tendency to unite with hydrogen fKan to 
remain combined with the other element, conse- 
quently the oxid is decomposed, water is formed 
and passes off as steam, while the metal remains. 
CuO + H, = H20 + Cu 
Cupric 
oxid. 
Hydrogen. 
Water. 
Copper. 
Such an action is called a deoxidation or a reduc- 
tion, and any substance which, like hydrogen, 
has a tendency thus to remove oxvgehirom its 
compounds is said to be a de&cidizing or reducing 
agent. 
OXYGEN. O". 16. 
55. What are the symbol, valence, and atomic 
and molecular weights of oxygen ? 
O. Bivalent. Atomic weight = 16. Mole- 
cular weight = 32. 
56. How does 0 exist in nature ? 
It is the most abundant of the elements. Ex- 
ists free in atmospheric air, and in combination 
in a great number of substances. 
57. How is it prepared? 
By decomposing a compound rich in oxygen. 
Potassium chlorate is generally decomposed by 
heat., when oxygen is given off and potassium 
chlorid remains. The chlorate is heated in a 
retort of difficultly fusible glass, or preferably 
of metal, which should not be more than a third CHEMISTRY AND TOXICOLOGY. 
21 
or half full ; the gas is collected over water. By 
mixing with the chlorate an equal weight of 
manganese dioxid the liberation of oxygen takes 
place at a lower temperature. When this mix- 
ture is used, care must be had that the manganese 
compound has not been adulterated, and that no 
organic matter is present, lest an explosion oc- 
cur. The gas produced from this mixture must 
be washed by causing it to bubble through a 
solution of potash to separate a small quantity 
of chlorin which is formed. This precaution is 
essential if the gas is to be used for inhalation. 
Oxygen is also prepared : 
1. By the electrolysis of water. 2. By heating 
certain oxids and peroxids. 3. By the action of 
sulfuric acid on compounds rich in O. 4. By the 
mutual decomposition of potassium permanga- 
nate and hydrogen peroxid, etc. 
58. State the more prominent physical properties 
of 0. 
It is a colorless, odorless, tasteless gas ; heavier 
than air (sp. gr. 1.108, air = 1). Sparingly solu- 
ble in water; more readily soluble in absolute 
alcohol. It liquefies at —140° (—229° F.) under 
a pressure of 300 atmospheres. The liquid boils 
at —187°.4 (—294°.5 F.), 
59. Does 0 unite readily with other elements? 
Very readily, and compounds of oxygen w'ith 
all other elements except fluorin are known. 
60. What is a compound of O with another ele- 
ment called ? 
An oxid. 
61. What is meant by oxidation and combustion ? 
By oxidation we mean the act of union of oxy- ESSENTIALS OP 
gen with another element. This process is at- 
tended by the liberation of heat, and, when it 
takes place rapidly, of light. The rusting of a 
given weight of iron is a slow oxidation, while 
the burning of the same in oxygen is a rapid oxi- 
dation. Only the latter produces light, while in 
both cases the same amount of heat is liberated. 
By combustion, in a general sense, is'nieanQEe 
rapid union of the oxygen of the air wTThsome 
other substance, as coal or phosphorus. In a 
wider sense, however, combustion maybe defined 
as any chemical union of two substances attended 
by liberation of heat and light. 
62. What are meant by combustibles and sup- 
porters of combustion ? 
By a combustible we understand a substance 
having ~a great tendency to unite rapidly with 
oxygen, such as phosphorus and sulfur. Such 
substances burn with greater brilliancy in pure 
oxygen than in air, which is oxygen in a diluted 
form. By supporters of combustion we mean 
gases with which substances of the last class 
enter into chemical action attended by light and 
heat. 
'*6n. Is the distinction in the last section a scien- 
tific one ? 
No. The process of combustion being a union 
of two substances, each of these takes an equal 
part in the reaction. The air or oxygen burns 
quite as much as the jet of illuminating gas 
which we say burns ; indeed, we may light a jet 
of oxygen in an atmosphere of coal gas, when it 
will burn as would a jet of coal gas in an at- 
mosphere of oxygen. CHEMISTRY AND TOXICOLOGY. 
23 
64. When we burn a candle, what takes place, 
and how does the sum of the weights of the products 
compare with that of the candle ? 
The substance of the candle is made up prin- 
cipally of two elements, carbon and hydrogen ; 
which, uniting with the oxygen of the air, form 
compounds called carbonic anhydrid and water. 
The former is an invisible gas and the latter 
passes off as steam. If, by a suitable arrange- 
ment, we collect and weigh these products of the 
combustion, we find that their united weight is 
greater than that of the candle, and this increase 
in weight is equal to the weight of the oxygen 
which has been abstracted from the air and 
united to the carbon and hydrogen# 
65. Of what importance is oxygen in respiration ? 
It is the only substance capable of maintaining 
the process for any length of time, and will only 
do so when suitably diluted with an inert gas, 
such as nitrogen. The principal purpose of respi- 
ration is to furnish oxygen for the oxidations oc- 
curring in the body. The blood in the lungs 
gives off carbonic anhydrid, which results from 
the oxidation of carbon, and water, which re- 
sults from the oxidation of hydrogen. At the 
same time it removes oxygen from the air. This 
oxygen is then carried to the' various tissues, 
composed largely of carbon and hydrogen. Oxi- 
dation takes place here, with the production of 
carbonic anhydrid and water, while heat is libe- 
rated. 
66. What is an “ anhydrid ” ? 
An oxid capable of combining with water to 
form an acid. Thus, S03 is called sulfuric anhy- 24 
ESSENTIALS OF 
drid because : S03 -+- H20 = H2S04 = sulfuric 
acid. 
67. What are ‘ ‘ basic oxids ’’ ? 
Oxids which combine with water to form bases. 
Thu§7 quicklime is a basic oxid, because it com- 
bines with water to form tile base Call202. 
68. What arc, “ neutral, saline, or indifferent 
oxids ” ? 
Oxids which are either essentially neutral, as 
water ; or are formed by the union of two other 
oxids, as the red oxid of lead, Pb304, which is a 
union of 2(PbO) and Pb02. 
69. What is ozone f 
Oxygen in a peculiar condition of condensa- 
tion. The molecule of oxygen is made up of 
two atoms, while that of ozone contains three. 
70. Under what conditions is ozone, farmed, and 
to what extent ? 
Pure liquid ozone has been obtained by sub- 
jecting ozonized oxygen to the temperature of 
liquid oxygen at the atmospheric pressure. 
In diluted form it is prepared by passing silent 
electric discharges through cold, dry air or oxy- 
gen ; by the actiou of concentrated sulfuric acicl 
on barium dioxid ; by slow oxidation of phos- 
phorus in damp air; by the decomposition of 
water by the battery. 
The first-mentioned method gives the best 
yield, which, under most favorable conditions, 
does not contain more than ten percent, of ozone. 
71. What are the properties of ozone ? 
The purg .liquid is dark blue, almost opaque, 
and evaporates to a bluish gas. 
In the dilute form it is slowly converted into CHEMISTRY AND TOXICOLOGY. 
25 
ordinary oxygen in the presence of water at 100° 
(212° F.), a change which takes place rapidly at 
237° (459° F.). It is a powerful oxidant. 
72. Describe the tests for ozone. 
1. Neutral litmus paper, impregnated with so- 
lution of potassium iodid, is turned blue by 
ozone. The same paper, without iodid, is not 
affected. 
2. Paper impregnated with a solution of a 
thallous salt is turned brown. 
3. Metallic silver is blackened by it. j 
73. How many compounds of hydrogen and oxy- 
gen are known, and what are they ? 
Two : 
Hydrogen monoxid, or water, H20 
dioxid or peroxid, H2Oa 
74. Describe the physical properties of water. 
Below 0° (32° F.), it is a crystalline solid (ice. 
snow). Above that temperature and below 100° 
(212° F.), at a barometric pressure of 760 mm., it 
is a liquid which boils at Jdie temperature named. 
Its boiling point is" elevated by increased pres- 
sure, and falls with “diminished pressure. Its 
vapor is colorless and transparent. Tt is an ex- 
cellent solvent, 
75. In what way is the solubility of solids in 
water affected by variations in teinpe.rjit.uve ? 
rule, the amount of a solid which a given 
volume can dissolve increases as the temperature 
is raised. 
COMPOUNDS OP HYDROGEN AND OXYGEN. 26 
ESSENTIALS OF 
There are exceptions. Thus, common salt is 
nearly equally soluble at all temperatures. The 
solubility of disodic sulfate increases rapidly 
up to 33 (91°.4F.), and then diminishes nearly 
as rapidly at higher temperatures. A few sol- 
ids, like the hydroxid and citrate of calcium, 
are more soluble at low than at high tempera- 
tures. 
76. How is the solubility of gases in water in- 
fluenced by variations in temperature and pres- 
sure? 
All gases (except hydrogen) arc the more solu- 
ble the lower the temperature and the greater 
the pressure. 
77. What is a saturated solution ? 
One containing as much of the dissolved sub- 
stance as can be dissolved at the existing tem- 
perature and pressure. 
78. Explain what is understood by physical and 
what by chemical solution. 
In a physical solution there is no modification 
of the solvent or substance dissolved"- Such a 
solution, on evaporation, deposits the dissolved 
solid unaltered. 
In chemical solution, the solvent and dissolved 
substance act upon each other to produce a new 
substance, which is then dissolved. Such a solu- 
tion does not leave tlie substance originally dis- 
solved when it is evaporated. 
79. What is water of crystallization, and what 
symbol is used to denote it ? 
Many substances, upon assuming the crystal- 
line form, take with them a definite number of 
molecules of water, which are .necessary to the  AND TOXICOLOGY. 
27 
maintenance of the peculiar form, and frequent- 
ly of the color, but which in no way modify the 
chemical properties of the substance! Tliis is 
called water of crystallization, and is denoted by 
the symbol Aq (Latin aqua = water)?" 
Sodic sulfate with 10 molecules 
water of crystallization. 
Na2S04, lOAq 
80. Explain the meanings of the terms anhy- 
drous. deliquescent, and efflorescent. 
A substance is anhydrous when it contains no 
water. A 'deliquescent substance is a solid ~th at 
has such a tendency to unite with water that it 
absorbs it from the air, becoming damp, and 
finally liquid. Crystalline bodies effloresce when, 
on exposure to air, they lose their water of crys- 
tallization and fall to powden 
81. How can "we prove by analysis that water has 
the composition If 0 ? ( See Q. 12.) 
If we pass the current of a battery through 
acidulated water, the water is decomposed into 
its constituent gases, and, collecting these sepa- 
rately, we finTTone to be pure hydrogen and the 
other pure oxygen. For every one volume of 
oxygen collected we will obtain two volumes of 
hydrogen, and if we weigh these gases we will 
find that the hydrogen formed weighing 2, the 
oxygen will weigh 16 ; and as each atom of oxy- 
gen weighs 16, and each atom of hydrogen 1, the 
molecule of water is composed of one atom of 
oxygen combined with twojitoms of. hydrogen, 
and its formula is consequently HaO. 28 
ESSENTIALS OF 
82. How can we prove synthetically that the com- 
position of water is HH) ? (See Q. 12.) 
1. If we make a mixture of 2 volumes of hydro- 
geu 1 volume of oxygen, and pass through 
it an electric discharge, chemical union will take 
place, the gases will disappear entirely, and in 
their place will remain a small quantity of water. 
2. If we burn hydrogen in an atmosphere of 
oxygen, and collect the result, we will find it to 
be water. If in No. 1 we use more than 2 vol- 
umes of hydrogen, or more than 1 volume of 
oxygen, the excess will remain after the union. 
This is in obedience to the law of definite pro- 
portions. 
83. What influence has temperature upon a 
mixture of oxygen and hydrogen ? 
At the ordinary temperature a mixture of oxy- 
gen and hydrogen remains such indefinitely, uo 
chemical union taking place; but if the tempe- 
rature be raised even at a single point in the 
mixture, as by applying a lighted match, or by 
the passage of an electric discharge, union takes 
place, and proceeds through the entire mass with 
great rapidity, causing a violent explosion. 
This influence of temperature upon chemical 
action is one of great importance, and not to be 
lost sight of, especially in animal chemistry, as 
certain actions take place at the temperature of 
the body which are arrested when the tempera- 
ture is raised or lowered a few degrees. 
84. What precaution is to be observed in experi- 
menting with hydrogen ? 
As mixtures of hydrogen and air in certain 
proportions explode violently on contact with CHEMISTRY AND TOXICOLOGY. 
29 
flame, the latter should be completely expelled 
from the generator before the former is col- 
lected. Hydrogen, being exceedingly diffusible, 
should be freshly prepared when needed, lest it 
become mixed with air. Neglect of these pre- 
cautions may cause serious accident. 
85. What is an hydroxid? 
A compound produced by the replacement of 
one-half the hydrogen of water by another 
ment or a radical (see Q. 688): e.gpotassium 
hydroxid, KHO ; calcium hydroxid, CaH^OTT" 
86. What is a hydrate? 
A compound containing chemically combined 
wate'f.' "Thus, the crystalline solid is 
ajiydrate of sulfuric acid, H2S04. 
~~WI. What is hydroxyl or oxhydryl? 
The group of atoms OH left by removal of 
H from HiQ. 
”88! ’ How are natural waters classified ? 
First, into unnotable and potable. The former 
are obviously unfit for drinking, as sea water. 
The latter are apparently"fit for domestic use. 
Potable waters are classified into : 
A. Meteoric waters—rain water, snpw water. 
B. Surface waters—rivers', laSes, ponds. 
C. Ground waters—water saturating the su- 
perficial porous stratum of the earth: e.g., well 
water. 
D. Deep waters—those coming from below an 
impervious stratum: e.g., spring and artesian- 
well waters. 
89. Which of these waters are most frequently 
contaminated ? 
Surface waters and ground waters. (See Q. 96.) 30 
ESSENTIALS OF 
90. What substances render a water unfit fieri' 
drinking ? 
1. An excess of solid matter, as in sea water 
and the water of mineral springs. 2. An excess 
of organic matter. 3. Poisonous metals, as lead 
or copper. 
91. What is meant by organic imjmrity ? 
Low forms of vegetable life ; decomposing 
animal or vegetable matter ; contamination from 
admixture of sewage or of discharges from tan- 
neries and from certain factories. 
92. Give a rough method of detecting organic 
impurity. 
Put a pint of water into a perfectly clean quart 
bottle, cork and shake strongly, remove the cork, 
and inhale the air of the bottle. If the water be 
much contaminated, and if the observer’s sense 
of smell be acute, an offensive odor will be ob- 
served. 
Note.—This method is quite rough, and only very bad 
water will produce an odor. The best method of deter- 
mining accurately to what extent a water is contaminated 
with organic matter is by the use of Wanklyn’s process, 
which, unfortunately, is not adapted to the use of medi- 
cal practitioners. See Manual, pp. 69-72. 
93. What waters are most liable to organic con- 
tamination ? 
That of stagnant pools. That of rivers having 
a sluggish stream or flowing through towns or 
manufacturing districts. That of wells. 
94. What poisonous metal occurs most frequently, 
and how may it be detected ? 
Lead. Take two tumblers full of the water, 
place them upon a sheet of white paper, and add CHEMISTRY AND TOXICOLOGY. 
31 
colorless ammonium sulfliydrate solution to one 
tumbler, and afterward hydrochloric acid. If 
the water to which the first reagent has been added 
becomes perceptibly darker than the other, and 
does not become colorless with hydrochloric acid, 
it is contaminated with lead or copper. 
95. What influence has the purity of icater upon 
its power of dissolving lead? 
Perfectly pure, unaerated water has no action 
upon lead, and a bright strip of the metal will 
retain its lustre in it indefinitely. But if the 
water contain air in solution, the lead becomes 
oxidized, and the oxid dissolves in the water: the 
solvent power of the water Being"increased by 
the presence of chlorids or nitrates. IfT* on the 
other hand, the water Hold involution sulfategjpr 
carbonates or carbonic anhydrid (commonly called 
carbonic acid gas) in small amount, its power, of 
dissolving lead is very much diminished, because 
these form upon the surface of the a. cnat- 
ing of lead sulfate or carbonate, which are com- 
pounds insoluble in water, and which protect the 
lead from any’TurEHef action of thfiJvater, 
96. What practii■dTThifiaJJions may he drawn 
from the last answer? 
1. Rain water should never be collected from 
roofs covered with lead, or in leaden tanks, be- 
cause such water contains no fixed* solids and is 
liable to contain nitric agid- utwJVmtrates ; its sol- 
vent power for leaiTis therefore comparatively 
great. * 2. A well or vessel for containing water 
should never have a leaden cover, because the 
water, evaporating from the surface, condenses 
upon the lead in a very pure form, as far as solids 32 
KSSiNTlA't^'O'P' 
are concerned, but highly aerated ; it thus dis- 
solves a portion of the oxidized metal, and, falling, 
carries it into the mass below. 
97. Explain what is meant by hard and soft 
water, and the cause of hardness, 
A water is said to be hard when it forms a 
curdy deposit with soap, and soft when soap dis- 
solves in ir without precipitation. - The curdy 
deposit. consists of tlie calcium ~and magnesium 
salts'of the fatty acids! which are insoluble in 
water, and its formation indicates an excess of the 
salts of those metals. 
98. What 'is the difference between temporary 
and permanent hardness, and to what is it due? 
Temporary hardness is removed by boiling and 
filtering from the deposit .stHwoduced. Tempo- 
rary Iiardness is due to bicarbonates of calcium 
and magnesium, which are soluble, but decom- 
posed by boiling, with expulsion of carbon dioxid 
and precipitation of the insoluble carbonate. 
Permanent hardness is due to the sulfates, which 
are not decomposed by boiling*, 
9y. What are'lhe physical characters of a good 
drinking water ? 
It must be neither flat, salty, sweetish, nor 
otherwise disagreeable in taste ; cool, limpid, 
clear, odorless ; and capable of dissolving soap, 
without formation of a curdy precipitate./ 
N. B.—A water which does not fulfil these 
conditions is certainly unfit, one which does is 
not necessarily fit for drinking. See Manual, pp. 
68-78. 
100. How may impure water be completely or 
partially purified for drinking purposes ? CHEMISTRY AND TOXICOLOGY. 
33 
Completely by distillation, but the product is 
flat" inTaste unless subsequently aerated and 
charged with a small quantity of salts. Par- 
tially by filtration and by boiling. The former 
process removes suspended impurities, and, if 
freshly-burnt animal charcoal be the filtering 
medium, dissolved impurities to some extent. 
By boiling, the water is softened, if temporarily 
hard, and, if the boiling be continued for half an 
hour, the probability of transmission of disease 
by bacteria is much diminished, if not removed. 
(See Manual, pp. 73-75.) . 
101. Where does water exist in the animal econ- 
omy? 
In all parts. 
102. What functions does water perform in the 
economy ? 
In the liquid parts it holds the solids in solu- 
tion (and it is of all liquids the best solvent we 
have); in the semi-solids it maintains the peculiar 
consistence of these parts. Many of the constitu- 
ents of the body contain water as a part of their 
composition, and, when this water is driven off, 
their condition becomes so altered as to render 
them entirely unfit for the performance of their 
functions. 
luis. By what channels is water eliminated from 
the system, and how does the amount discharged 
compare with that ingested ? 
It is discharged in the urine, perspiration, ex- 
pired air, and faeces. The amount discharged is 
greater than that ingested, the excess being 
formed by the oxidation of the hydrogen con- 
tained organic matters of the body. ESSENTIALS OF 
104. What is the formula of hydrogen dioxid; 
and under what other names is it known ? 
H202. Hydrogen peroxid ; peroxide of hydro- 
gen ; oxygenated water ; golden liquid. 
105. Describe its properties. 
In the pure form a colorless, syrupy liquid, 
heavier than water, having a disagreeable metal- 
lic taste. In solution in water of 10 to 20 vol- 
ume strength, a colorless liquid. 
It is a powerful oxidizing agent, and in some 
cases also acts as a reducer. It is a strong 
bleacher and disinfector. The pure substance 
yields 475 times its volume of oxygen when de- 
composed. The solution customarily used, 10 to 
20 volumes. 
106. For what purposes is it used? 
As a disinfectant; as a bleacher ; in the labora- 
tory as an oxidizer and for many other purposes; 
for bleaching hair. 
107. Describe a reaction given by //202 but not 
by ozone. 
Add to the liquid a few drops of potassium 
dichromate solution and a little dilute sulfuric 
acid, and agitate with ether. The ether assumes 
a brilliant blue-violet color in the presence of 
H202. 
' (See Manual, pp. 77, 78.) CHEMISTRY AND TOXICOLOGY. 
35 
CLASS II. ACIDULOUS ELEMENTS. 
108. What are the characteristics of the acidu- 
lous elements ? 
Their oxids combine with water to form acids, 
never to form bases. They do not displace the 
hydrogen of oxvacids to form oxvsalts 
109. What name is sometimes used to designate 
the elements of thjs class ? 
The metalloids. 
1 lU!"IV/me the principal elements included in 
this class. 
Chlorin, bromin. iodin, sulfur, nitrogen, phos- 
phorus, arsenic, antimony, boron, carbon, and 
silicon.' 
GROUP I. THE HALOGENS 
Fluorin F . 19. 
Chlorin .Cl 35".5 
'Bromin Br 80. 
Iodin 1 127. 
111. Name the elements constituting the chlorin 
group. 
Fluorin, chlojin, bromin, ioj^jn. 
112. JJescriSe the common properties of the ele- 
ments of this group. 
They are univalent. They form compounds 36 
ESSENTIALS OF 
with hydrogen, containing one volume of the 
element, in the gaseous state, combined with one 
volume of hydrogen, which are monobasic acids. 
Their hydroxids are monobasic acids (fluorin 
forms no hvdroxidl. They are all possessed of 
bleaching and disinfecting powers, 
lid. What name is applied to the group ? 
The halogens. 
FLUORIN. 
114. What are the symbol, and atomic and 
molecular weights offluorin ? 
F. 19. 8g. 
the prominent properties of fluorin. 
A yellowish-green gas. Decomposes__J3jO 
with formation of IIF and ozone. Detonates 
violently on contact' with H. Attacks organic 
substances energetically. In it Si, Do, As, Sb, 
S, and I ignite spontaneously. 
116. What compound offluorin with hydrogen is 
known, and what are its uses and properties ? 
Hydrofluoric acid, or hydrogen fluorid, HF. 
A colorless gas, soluble in water, highly acid and 
corrosive* It is used, either as gas or m solution, 
foretelling on glass, which it attacks with great 
energy. 
117. How is HF obtained, and what precautions 
are to be observed f 
It is prepared by the action of sulfuric acid 
upon fluorspar : 
Calcium 
fluorid. 
CaF2 + HaS04 = CaS04 + 2HF 
Sulfuric 
acid. 
Calcium 
sulfate. 
Hydrogen 
fluorid. CHEMISTRY AND TOXICOLOGY. 
37 
The operation must be performed in vessels of 
lead or of platinum. 
Great care is to be had that the gas is not 
inhaled, and that the skin is not exposed to it, 
as, in a few instants, it produces painful_blisters, 
afterwards forming open wounds, whiclf are vgyy 
painful and heal with great difficulty^ 
118. What are the symbol, and atomic and 
molecular weights of chlorin ? 
Symbol Cl. Atomic weight 35.5. Molecular 
weight 71. 
119. How does it exist in nature? 
It is not found free, but is very abundant in 
combination, notably in common salt. 
120. How is it prepared ? » 
There are three principal .methods: 1. By the 
decomposition of its hydrogen compound {i.e., 
muriatic acid) by black oxid of manganese : 
CHLORIN. 
MnOa + 4HC1 = MnCl, + 2H,0 + Cla 
Manganese 
dioxid. 
Hydrochloric 
acid. 
Manganous 
chlorid. 
Water. 
Chlorin. 
2. By decomposition of common salt, 1 part of 
which, mixed with 1 part of finely powdered 
manganese dioxid. is heated with 3 parts com- 
mercial sulfuric acid. 3. When comparatively 
small quantities of Cl are required, it may be 
obtained by exposing chloride of lime, moistened 
with water or with dilute acid. This is a conve- 
nient method when ffie gas is required .for disiac 
fection of limited spaces or for inhalation? 38 
ESSENTIALS OF 
121. State the more prominent physical proper- 
ties of Cl. 
It is a greenish-yellow gas, having a very 
penetrating, suffocating odor, acting energeti- 
cally upon the air-passages even when dilute, 
producing coughing, inflammation, and haemo- 
ptysis. It is2£ times heavier than air, and, as it 
is quite soluble in water, should be collected by 
allowing the delivery tube to reach to the bottom 
of a jar, whose opening is directed upwards,when 
the Cl collects from the bottom, driving the air 
out above it. It is liquefied by a pressure of 
atmospheres, and liquid chlorin is now used in- 
dustrially. 
122. What is aqua chlori (U. S.), or liquor 
chlori (Br.)? 
A solution of Cl in water, saturated at the tem- 
perature of the air. 
123. Does Cl unite with other elements readily ? 
It does. It unites directly with all elements 
except fluorin, oxygen, nitrogen, and carbon, and 
with th"ese it unites indirectly. This union of Cl 
with other elembfits is frequently attended by the 
appearance of light and heat: When a candle is 
burnt in Cl, the hydrogen of the candle unites 
directly with the Cl, giving off light and 
while the carbon, being incapable of union with 
Cl under these conditions, rises as a dense smoke. 
124. When chlorin and hydrogen combine, what 
substance is formed? 
Hydrochloric acid. 
125. In what proportionate volumes do these two 
gases combine ? 
In equal volumes. CHEMISTRY AND TOXICOLOGY. 
39 
126. Under what conditions does the combina- 
tion occur ? 
A mixture of Cl and H may be kept indefinitely 
at oldmary temperatures, and in the dark, with- 
out union taking place. When the" mixture is 
exposed to diffuse sunlight the combination takes 
place gradually, but if the mixture be exposed 
to the direct rays of the sun, or to certain strong 
artificial lights, or if a spark be passed through 
the mixture, combination occurs instantly with 
an explosion. 
127. TVKat change takes place when a solution of 
Cl in Hi 0 is exposed to light ? 
Under the influence of light, Cl decomposes 
II20, with formation of hydrochloric acid, while 
O is liberated : 
2H20 + 2C12 = 4HC1 + 02 
Water. 
Chlorin. 
Hydrochloric 
acid. 
Oxygen. 
128. If hy is the equation in the last answer not 
written II20 + 2C1 = 2HC1 + O ? 
Because that would indicate that a single atom 
of O could exist uncombined. Atoms, when 
liberated from one combination, immediately 
combine with other atoms to form new molecules 
(see Q. 8). 
129. How does Cl act as a bleaching, deodoriz- 
ing, and disinfecting agent ? 
Indirectly as a powerful oxidizing; agent. It 
decomposes the H20 present, according to the 
equation given above, and the_D, being in the 
nascent state, acts energetically. Cl will not 
bleach a perfectly dry~subs£ance. 40 
ESSENTIALS OF 
130. What is meant by the nascent state, and 
how is the superior energy of elements in this state 
explained ? 
An element is said to be in the nascent state 
(the state of being born) at the instant that it is 
set free from one of its compounds. Free oxy- 
gen exists as a collection of molecules of oxygen, 
each molecule consisting of two atoms. "When 
oxygen is liberated from a compound it is set 
free, first as individual atoms; these, however, 
not being capable of existing free, immediately 
unite in pairs to form molecules. But if, at the 
instant at which oxygen is liberated, there be 
present any substance with winch oxygen has a 
great tendency to combine, its atoms enter into 
combination with this rather than with each 
other. As the force required to break up the 
molecule of oxygen is in this case not required, 
the combination takes place readily. 
131. What are the names and formula of the 
compound of chlorin and hydrogen ? 
Hydrogen chlorid, or hydrochloric acid—HC1. 
132. What are the physical pi'operties of this 
substance ? 
It is a colorless gas ; gives off thick white 
fumes on contact with moist air; has a very 
sharp, penetrating odor, producing great irrita- 
tion of the respiratory passages and attacking 
the skin ; reddens litmus; does not burn in air 
or support combustion ; exceedingly soluble in 
water ; heavier than air. Sp. gr. 1.293. 
133. What are the hydrochloric or muriatic 
acids of the arts and pharmacy ? 
Solutions of this gas in water, of varying 
strength and purity. CHEMISTRY AND TOXICOLOGY. 
41 
134. What varieties are there? Describe them. 
Commercial: A yellow liquid, having usually 
a sp. gr. of about 1.16 ; contaminated with iron 
and chlorids of sodium and arsenic ; used for 
manufacturing and rough chemical purposes. 
Pure7 Acidum hydrochloricum, U. S., Br. A 
colorless liquid, being a pure solution of HC1 in 
water, of about the same strength as the last. 
Sp. gr. 1.16. 
Acidum hydrochloricum dilutum, U. S., Br. 
The last-named diluted with water to sp. gr. 
1.049 = 10 per cent. HC1 (U. S.); sp. gr. 1.052 = 
10.5 per cent. HC1 (Br.). 
135. Name the tKree strong mineral acids. 
Hydrochloric, sulfuric, and nitric acids. 
136. What is the action of hydrochloric acid 
with a metallic oxid or hydroxid? 
Both are decomposed, while water and a chlo- 
rid are,formed, thus: 
CaO + 2HC1 = CaCl2 + H20 
Calcium 
oxid. 
Hydrochloric 
acid. 
Calcium 
chlorid. 
Water, 
NaHO + HC1 = NaCl + II30 
Sodium 
hydroxid. 
Hydrochloric 
acid. 
Sodium 
chlorid. 
Water. 
137. What is arjua regia? 
A mixture of nitric and hydrochloric acids in 
the proportion of IHNOs to 3HC1, or three parts 
by weight of nitric acid to five of hydrochloric. 
The acids react upon each other with liberation 
of Cl. which, being in the nascent state, com- 
bines with the noble metals, gold arid platinum, 
if they be present. From this fact the name is 42 
ESSENTIALS OF 
derived, gold having been considered by the 
older chemists as the king of metals. The mix- 
ture is also known as nitrohydrochloric or nitro- 
muriatic acid. 
In the dilute form, it is used in medicine under 
the name Acidum nitrohydroehloricum, U. 8., Br. 
138. Describe the tests for the soluble chloride 
and hydrochloric acid. 
1. With silver nitrate, a white, flocculent pre- 
cipitate, insoluble in nitric acid, readily soluble 
in ammonium hydroxid. 
2. With mercurous nitrate, a white precipi- 
tate, turning black on addition of ammonium 
hydroxid. 
139. What chlorids are insoluble or very diffi- 
cultly soluble in water ? 
Those of lead, shyer, and mercury (calomel). 
140. How may they be distinguished from each 
other? 
By adding ammonium hydroxid. If the sub- 
stance be silver chlorid it is dissolved, if it be 
mercurous chlorid it turns black, and if it belead 
chlorid it remains unaltered. 
141. Does free' hydrochloric acid exist in the 
body ? 
Yes. It is the free acid of the gastric juice. 
142. Define a poison. 
Any substance which, being in solution in 
the blood, may produce death or 'serious bodfly 
hj&rbj. 
143. Define a corrosive. 
A substance capable of producing death or 
injury'by’Its chemical action upon a tissue with 
which it comes in direct contact. CHEMISTRY AND TOXICOLOGY. 
144. In what other respects do corrosives and 
poisons differ? 
Corrosives act upon dead and living tissue 
alike, while poisons, as a rule, do not. The vio- 
lence of cotMsion is directly proportionate to 
the degreejof concentration, while the action of 
poisons depends ujRTn the actual quantity ab- 
sorbed, but in no wise on ffre~Tfcgrce of concent ra- 
by destroying the skin, producing an injury re- 
sembling a burn; the poisons, if applied to the 
skirl, act only when absorbed. 
T45. May the same substance be a corrosive and 
also a poison? 
Yes. Oxalic acid in concentrated solution acts 
primarily as a corrosive. In dilute solution it 
does not oorrodfTTie stomach, but acts as4 poison. 
Are the mineral nr.ids poisons or corrosir.es ? 
They are corrosives. 
147. Describe the prominent symptoms produced 
by the mineral acids. 
Acute, burning pain, extending from the mouth 
to the stomach, referred chiefly to the epigastrium, 
and beginning immediately. Violent aDd distress- 
ing vomiting of dark, tarry, or “coffee-ground ” 
and highly acid material. Eschars, at first white 
or gray, later brown or black, are formed where 
the acid has come in contact with the "Skin, lips, 
or tongue. 
148. How does death occur? 
Either within twenty-four hours from collapse; 
more suddenly from perforation and opening of 
large blood vessels; or after several weeks or 
months from starvation, due to destruction of 44 
ESSENTIALS OP 
gastric cells or closure of the pylorus by inflam- 
matory thickening. 
149 In what respects does hydrochloric acid dif- 
fer from nitric and sulfuric in its action on the 
economy f 
The HC1 gas, escaping from the solution, enters 
the air passages, and causes serious interference 
with respiration, dyspnoea, stridulous, frequent, 
and moaning breathing, and loss of articula- 
tion. 
150. What should be the treatment in corrosion 
by mineral acids ? 
The object is to dilute and to neutralize the 
acid and convert it into a harmless salt. For this 
purpose the best agent is magnesia (magnesia 
usta) suspended in water j~ or. if this be not at 
hand, a strong solution of soap. Chalk and the 
carbonates or bicarbonates of sodium and potas- 
sium should not be given, as they generate large 
volumes of gas. The scrapings of a plastered 
wall are entirely useless. The stomach pump, or 
any attempt at the introduction of a tube into the 
oesophagus, is not to be thought oi.t 
151. Describe the post-mortem appearances caused 
by hydrochloric acid. 
The pharynx,larynx, and oesophagus are highly 
inflamed ; the mucous membrane sloughed off in 
places. The internal surface of the stomach is 
dark red or even black ; the walls much thinned, 
or even perforated and softened. If death has 
resulted secondarily (see Q. 148), more or less of 
the stomach is found white or gray and thickened, 
particularly at the pylorus, which may be so 
small as not to admit a fine knitting needle.v CHEMISTRY AND TOXICOLOGY. 
45 
152. What is a general characteristic of the 
compounds of chlorin with oxygen ? 
They are all very unstable, being decomposed 
by very slight influences and frequently with 
explosion. 
BROMIN. 
153. What are the symbol, and atomic and mole- 
cular weights of bromin ? 
Symbol = Br. Atomic weight = 80. Molecu- 
lar weight = 16Q. 
154 What are its physical properties ? 
It is a dark-brown liquid, giving off brown 
fumes freely when exposed to the air ; has a 
strong, disagreeable odor, and is very irritating 
to mucous surfaces. It is sparingly soluble in 
water. 
To5. How does bromin exist in nature ? 
It is not found free, but exists in small pro- 
portion, widely diffused, however, in combina- 
tion with potassium, sodium, and magnesium, 
in seajflants, and in the waters of the sea ancTof 
certain mineral springs. 
156. How does bromin compare with chlorin in 
its chemical actions ? 
Its actions are very similar to those of chlo- 
rin, but less intense ; it forms compounds simi- 
lar to those of chlorin, and is a good bleaching 
and disinfecting agent. Chlorin drives bromin 
out of its combinations. When chlorin acls upon 
a bromid uTsolution, a chlorid is formed, while 
bromin is set jlfie. 
157. Describe the tests for a bromid. 
1. With silver nitrate solution, a yellowish- 46 
ESSENTIALS OF 
white precipitate, which is insoluble in. nitric 
acid ; soluble in a large excess of ammonium 
hydroxid. 
2. Add a few drops of chlorin water (to libe- 
rate the bromin), and then some chlorotprm ; 
shake ; the chloroform is colored yellow by bro- 
min. 
3. Repeat 2, using starch paste instead of 
chloroform ; the liquid is colored yellow. 
IODIN. 
158. Give the symbol, and atomic and molecular 
weights of iodin. 
Symbol = I. Atomic weight = 127. Mole- 
cular weight = 254. 
159. How does it occur in nature ? 
In the form of iodids in mineral waters, in sea 
water, and in animals and vegetables inhabiting 
tKeJatter.. 
160. Describe the principal physical properties 
of iodin. 
A blue-gray solid in scales, having a metallic 
lustre. Volatile at all temperatures, the vapor 
having a beautiful violet color and a peculiar 
odor. Fuses at 113°.6 C. (236°.5 F.). Dissolves 
readily in chloroform and in carbon disulfide 
forming violet-colored solutions ; also inT 
forming aTbrown solution. Sparingly soluble Jn 
Haq 
161. How may the of iodin in aqueous 
solution b< increased?. 
Water which stands in contact with excess of 
iodin continues to dissolve it. The HsO is par- CHEMISTRY AND TOXICOLOGY. 
47 
tially decomposed by the I, with formation of 
hydriodic acid (see Q. 162), in a solution of 
which I is more soluble than in pure HaO. 
The presence of certain__salls. as potassium 
iodid, ammonium chlorid and nitrate, etc., 
increases the solvent power of HaO for I. A 
solution ofj in potassium iodid solution is used 
medicinally under the of Lugol’s solution, 
or Liq. Iodi Comp., U. S.; Liquor fodi, Br. • 
162. Describe the chemical properties of iodin. 
They are very similar to those of Cl and Br, 
but less active than either, I being driven out of 
its binary compouncTsTiy either Cl or Br. It de- 
composes H20 slowly, and hydrogen sulfid rap- 
idly, with formation of hydriodic acid and libe- 
ration of O or sulfur. Nitric acid oxidizes it to 
iodic acid. 
163. How may free iodin or an iodid he de- 
tected ? 
1. Iodids with silver nitrate solution form a 
yellow precipitate, insoluble in nitric acid or in 
ammonium hydroxid. 
2. Add fuming nitric acid to solution of an 
iodid, then chloroform, and agitate; the chloro- 
form (lower) layer is colored violet. 
3. Add palladic chlorid to solution of an iodid; 
a dark-brown precipitate. 
4. Free iodin colors starch paste dark violet- 
blue. 
164. Wha t compound of hydrogen and iodin is 
known ? 
Hydriodic acid, or hydrogen iodid. HI. 
1 tio. What are its properties t 
It is a colorless gas, very soluble in water. 48 
ESSENTIALS OP 
Its concentrated aqueous solution has a strong 
acid reaction, and fumes when exposed to the 
air. It is decomposed by Cl, Br, oxidizing 
agents, sulfuric acid, etc,, etc. When exposed to 
the air, the oxygen unites with the hydrogen of 
the acid, forming water, while the iodin is seF 
tree, and dissolved in the remaining acid until 
this becomes saturated with iodin, when the re- 
mainder is precipitated in the solid form. It 
behaves with metals and their hydroxids like 
hydrochloric acid. • CHEMISTRY AND TOXICOLOGY. 
49 
GROUP II. SULFUR GROUP. 
Sulfur S 32. 
Selenium Se —79.5 
Tellurium Te 128. 
166. Describe the common properties of the ele- 
ments of this group. 
They are bivalent. Each forms a hydrogen 
compound, containing an atom of the element 
aiTft two”atoms of hydrogen, which is a weak, di- 
basic acid. Their oxyacids are all dibasic. 1 ~ 
167. What are the symbol, and atomic and mole- 
cular weights of sulfur ? 
Symbol = S. Atomic weight = 33. Mole- 
cular weight = 61. 
168. How does 8occur in nature? 
Free, and in combination in jmlfids, sulfates, 
and organic compounds. 
169. Describe me prominent physical properties, 
of sulfur. 
\ yellow, crystalline solid, white when in a 
finely-divided state, having faint though charac- 
teristic odor and taste. It fuses at 114° (237°.3 
F.). aiuP boils”! 130° (824° F.). It is insoluble 
in tIQ0, soluble in carbon disulfid and in proto- 
chlorid of sulfur. 
SULFUR. 50 
ESSENTIALS OP 
170. What is the *difference between roll sulfur 1 
flowers of sulfur, and precipitated sulfur? ) 
' Roll sulfur is' prepared by pouring melted S 
into moulds, which are cooled. Floicers of sulfur 
are obtained by mixing vapor of 8 with cold 
air, when the S assumes the solid form in small 
feathery crystals. Precipitated sulfur, or sulfur 
prcecipitatum, U. 8., is obtained by decomposing 
a sulfid, S being precipitated in the amorphous 
condition and in a very fine state of subdivi- 
sion. 
171. What occurs when sulfur is heated in con- 
tact with air ? 
It burns with a blue flame at about 250°, unit- 
ing with the O of the air to form sulfur dioxid— 
S02. 
172. Does sulfur unite directly with any other 
elements ? 
Yes; many metals burn in vapor of S, with 
formation of sulfids. Sulfur also burns in an 
atmosphere of H, with formation of hydrogen 
sulfid. 
178. What is an important compound of sulfur 
and hydrogen, and with what oxygen compound 
does it correspond f 
Hydrogen sulfid, also known as sulfuretted 
hydrogen—HaS. It corresponds with HaO. only 
in place of O there is S, and in each one atom of 
the bivalent O or S is united with two atoms of 
the univalent H: 
COMPOUNDS OP SULFUR. CHEMISTRY AND TOXICOLOGY. 
51 
H 
°( 
XH 
H 
K 
XH 
Water. 
(Hydrogen oxid.) 
Hydrogen sulfid. 
[There is another compound of S and H cor- 
responding to HaOa:] 
/H 
O' = HaOa 
xO—H 
/H 
S( =SaHa 
XS—H 
Hydrogen 
dioxid. 
Hydrogen 
disulfid. 
174. IIow may Hi8be prepared? 
By treating ferrous sulfid with dilute sulfuric 
acid : 
FeS + HaS04 = FeS04 + HaS 
Ferrous 
sulfid. 
Sulfuric 
acid. 
Ferrous 
sulfate. 
Hydrogen 
sulfid. 
Also by decomposing antimony trisulfid or 
calcium sulfid by HC1. 
175. What are the principal physical properties 
of hydrogen sulfid? 
It is a colorless gas, having an exceedingly 
offensive odor "oFrbtten eggs and a correspond- 
ingly disgusting taste. Heavier than air (sp. gr. 
1.19). Under a pressure of 17 atmospheres it 
forms a colorless, mobile fluid which crystallizes 
at—85° F.). ~BoIuble in water, the soTu: 
tion having an acid reaction, and being cTecom- 
posed with deposition of S when exposed to the 
air for some time. 52 
ESSENTIALS OP 
176. What a/i'e the products of combustion of 
IhS ? 
If the supply of O be small, with formation of 
H20 and deposition of solid 8 : 
Hydrogen 
sulfid. 
2H2S -t- 02 = 2H20 + S2 
Oxygen. 
Water. 
Sulfur. 
If, however, the supply of O be sufficient, the 
products are entirely gaseous : 
2H2S + 302 = 2H20 + 2SOa 
Hydrogen 
sulfid. 
Oxygen. 
Water. 
Sulfur 
dioxid. 
Mixtures of air or oxygen with H2S are explo- 
sive. 
177. When II2S is passed through a solution of 
a salt, what takes place ? 
Both the gas and the salt are decomposed, with 
formation of a sulfid, and regeneration of the 
acid T 
Cupric 
sulfate. 
CuS04 + H,S = CuS + HaS04 
Hydrogen 
sulfid. 
Cupric 
sulfid. 
Sulfuric 
acid. 
178. What use is made of this reaction in ana- 
lysis ? 
The sulfids of the different metals, formed as 
above, vary in their color and in their solubility 
in acidulated HaO ; therefore, by passing HaS 
through a solution, we can determine whether 
certain metals are present or not, according as 
insoluble, colored precipitates are or are not 
formed. (See Laboratory Guide, 8d Ed., pp. 
21-32.) CHEMISTRY AND TOXICOLOGY. 
53 
179. How may the presence of Hi8 or of a 
sulfid be detected ? 
1. HaS colors paper moistened with lead ace- 
tate solution brown‘ or black . 
2. HaS has the odor of rotten eggs. 
3. A sulfid is decomposed by HC1, yielding 
HaS, whose presence is then shoWfiTby 1 and 
2. 
180. In what gaseous mixtures does IfSoccur,? 
In sewer gas, in the emanations from dead 
bodtSSTand in the gases discharged from vol- 
canoes. 
181. What should be the treatment in IfS 
poisoning ? 
Plenty of fresh air, cold affusions, hot brandy 
and water, inhalation of chlorin largely diluted 
with air. 
182. What oxids of sulfur are known ? 
Sulfur dioxid, S02 
“ trioxid, S03 
183. What is another name for sulfur dioxid t 
Sulfurous anhydrid ; also improperly called 
sulfurous acid. 
184. Why is the name sulfurous acid an im- 
proper one for this compound ? 
Because it contains no H, which enters into the 
composition of every acid. The true sulfurous 
acid is a compound of the anhydrid with HjO : 
SOa + HaO = HaSOa 
SulfnTOus 
anhydrid. 
water: 
Sulfurous 
185. How may SOt be prepared? 
It is formed whenever S is burnt in air, and is 54 
ESSENTIALS OF 
also obtained by decomposing sulfuric acid with 
charcoal or metallic copper : 
Sulfuric 
acid. 
2HjS04 + C = 2SOa + COa + 2HsO 
Carbon. 
Sulfur 
dioxid. 
Carbon 
dioxid. 
Water. 
2H3SO4 + Cu = CuSO« + 2H,0 + S02 
Sulfuric 
acid. 
Copper. 
Cupric 
sulfate. 
Water. 
Sulfur 
dioxid. 
The copper or coal and the requisite sulfuric 
acid are placed in a flask, which is heated. 
~T86. Describe 'the principal physical "properties 
of SOi. 
A colorless gas, having a suffocating odor (sul- 
fur matches) and a disagreeable and persistent 
taste. More than twice as heavy as air (sp. gr. 
2.317). Liquefies at —10° (+14° P ). It is very 
soluble in HaO, which takes up about 40 times 
its volume at the ordinary temperature. 
187. What is the Acidum sulfurosum U. S., 
Br. ? 
An almost saturated solution of SOa in water. 
188. Is this simply a solution of SOa ? 
No ; it contains the true HaS03, sulfurous acid, 
formed by the union of SOa 4- H20. 
189. What is used for? 
As a bleaching and disinfecting agent, and in 
the manufacture of sulfuric acid. 
190. What action has S02 on the economy when 
inspired ? 
In a concentrated form it is poisonous. When 
diluted with air it produces irritation of the air 
passages. Individuals may, however, become by 
degrees habituated to its presence in air, in quan- CHEMISTRY AND TOXICOLOGY. 
55 
tities which would prove fatal to those not so 
trained. 
191. What substance is represented by the for- 
mula SOt? 
Sulfur trioxid, or sulfuric anhydrid. 
192. State the properties of S03. 
It occurs as long, colorless, transparent prisms, 
which at 18°.^(Bo'i F.) melt to an oily liquid, boil- 
ing at 46° (114°.8 F.) When exposed to_the air 
it gives off dense white fumes. In the*"aTjsence 
of 1I20 it has no effect upon litmus paper. It 
has a'great tendency to unite with HaO to form 
sulfuric acid, and if dropped into H20 pro- 
duces a hissing noise from the violence of the 
action. 
lUST What is the compound having the formula 
IliSOz f 
Sulfurous acid. 
194. Give the formula of sulfuric acid. 
H3S04. 
195. What is the common name of H3SOJ 
Oil of vitriol. 
1951 What is its basicity ? How many sulfates 
of sodium and of calcium are there, and what are 
they ? 
It is dibasic. There are two sulfates of so- 
dium : monosodic sulfate, NaHS04, and disodic 
sulfate, Na2S04 ; and one sulfate of calcium, 
calcium sulfate, CaS04. 
197. Give a general idea of the principle of 
manufacture of sulfuric acid. 
Sulfurous anhydrid is obtained by heating 
either S or a natural compound of S and iron, 
called iron pyrites, in a current of air. The 56 
ESSENTIALS OE 
anhydrid thus obtained is caused to unite with 
HaO and O : 
Sulfur 
dioxid. 
so2 + h2o + o = h2so4 
Water. 
Oxygen. 
Sulfuric 
acid. 
The actual reactions are : 
First. S02 is oxidized by nitric acid, with 
liberation of nitrogen tetroxid : 
Second. The nitrogen tetroxid so formed com- 
bines with H20 to regenerate nitric acid and form 
nitrogen dioxid : 
SOa + 2IINO3 = HaSO« + 2NOa. 
3NOa + HaO = 2HN03 + NO. 
Finally, the dioxid so produced is oxidized by 
air to the tetroxid, which again regenerates nitric 
acid : 
2N0 + 0„ = 2NOa. 
The nitric acid therefore acts as a carrier of O 
from the air to the S02. 
The acid so obtained is concentrated b£_ eva- 
poration of the H20 mixed with it, firstTn pans 
of lead, and subsequently in retorts of glass or 
platinum., 
198. Describe the 'prominent physical properties 
of pure HiSOi. 
A dense, oily, colorless liquid. Sp. gr. 1.842. 
Boils at 388° (640° F.), distilling in great part un- 
changed. Odorless, intensely acid in taste and 
reaction, and highly corrosive. Non-volatile at 
ordinary temperatures. CHEMISTRY AND TOXICOLOGY. 
57 
199. Describe the principal chemical characters 
of 1US0,. 
Heated with S, C, Hg, Cu, or Ag, it is reduced, 
with formation of S02. It has a great tendency 
to unite with ti20 toTorm definite hydrates, one 
of which, H3SQ4,ILO. crystallizes at 8°.f) (47°.3 
F.), and is known as glacial sulfuric acid. 
When H2S04 and HaO are mixed, there is 
marked elevation of temperature. H2S04 ab- 
sorbs 1I20 from the air, and removes its elements 
from organic substances, which are thereby 
blackened From liberation of their carbon, ije.. 
are charred, 
auu. fame and describe the varieties of this acid 
used in the arts and in pharmacy. 
Commercial: An oily liquid, with a brownish 
tinge "(due to charred organic matter), sp. gr. 
1.83 to 1.84, and containing 93 to 99| percent, of 
true H2S04. 
Pure: Acidum sulfuricum, U. S., Br.: a color- 
less, oily liquid, having sp. gr. 1.84. 
Acidum sulfuricum dilutum, U. 8., Br., is a 
dilute acid of 1.069 sp. gr. and 9 to_10 per cent. 
H2S04, U. 8.; sp. gr. 1.094 and 1216T3 per cent. 
tlvS04, Br. 
zui. What is Nordhausen sulfuric acid? 
A brown liquid, obtained by distilling green 
vitriol (FeSQi). and used in dyeing as a solvent 
or indigo. It is a mixture of S' >3 with pyro-sul- 
furic acid, H2OtS2, which is itself a compound of 
II2S04 + S03. 
202. Describe the tests for soluble sulfates or sul- 
furic acid. 
1. With barium chlorid, nitrate, or acetate, a 58 
ESSENTIALS OF 
white precipitate, insoluble in HC1 or in nitric 
acid. 
2. With lead acetate, a white precipitate, in- 
soluble in dilute acids. 
3. With calcium chlorid, a white precipitate, 
either immediately or on dilution with two vol- 
umes of alcohol; insoluble in dilute acids. 
Toxicology of H2SOi, see Q. 147-151. 
203. How may stains of sulfuric, hydrochloric, 
and nitric acids on cloth he distinguished from 
each other ? 
When not too old, stains of H2S04 and HC1 
are bright red, the latter the brighfet of the two. 
They disappear permanently when moistened 
with aqua ammonise. Those of nitric acid are of 
a yellowish tinge, and are not remove’cTby aqua 
ammonise. CHEMISTRY AND TOXICOLOGY. 
59 
GROUP III. NITROGEN GROUP. 
]SlTRO«EN N 14 
Phosphorus P 31 
Arsenic As 75 
Antimony Sb 120 
204. Describe the common properties of the ele- 
ments of this group. 
They are trivalent or quinquivalent. Each 
foriffint fiVdr6ggfi"T6mpound, containing three 
atoms of hydrogen, combined with one atom of 
the elementT These hydrogen compounds are 
nofT aci<T but basic in their natufgT The oxy- 
aciekrrttffer rtt basicity from monobasic to tetra- 
bastc; ~ 
NITROGEN. 
205. Give the symbol, and atomic and molecular 
weights of nitrogen. 
Symbol = N. Atomic weight = 14. Mole- 
cular weight = 28. 
206. Where does~Noccur in nature? 
Free in atmospheric air ; in combinationJii the 
nitrates, in ammoniacal salts, arid in'organic com- 
v VtfTTSta$e the more prominent properties of 
nitrogen. 
Itjs a colorless, odorless, tasteless gas ; lighter 
than air (sp. gr. 0.972 — air = Very spar- 60 
ESSENTIALS OP 
ingly soluble in water, more soluble in alcohol. 
Chemically, it is noticeable from its negative 
characters. It does not burn or support combus- 
tion. It does not unite with other elements 
directly, or does so with great_. difficulty. Its 
compounds are nearly all very_jprone to.decom- 
position. It does not support respiration, but 
has no positively deleterious action upon the 
economy. 
208. What are the constituents of atmospheric 
air ? 
Oxygen and nitrogen ; with small quantities 
of dSfBohic anhydfid, vapof'of water, ammonia, 
and nitric acid. 
“20tT ~ Whdfis the proportion by volume of nitro- 
gen to oxygen in air ? 
79 of nitrogen to 21 of oxygen. 
2T0. Does this proportion vary much in free 
air ? 
No. Although air is a mere mixture, the pro- 
portion of its chief constituents remains prettv 
much the saTneat different times, seasons, and* 
elevations above the sea level. 
<jil. WhaTTs observed with regard to the solubil- 
ity of air in water ? 
All water, even that which has been recently 
distilled, contains air in solution, and it is from 
the air so held in solution that aquatic animals, 
Iffcathing by means of gills, obtain the oxygen 
wTltCimfey require. ~ As air is a mixture, it has 
noCrSdlPbimy of its__owu, but each constituent 
gas is~dlssol vecTaccording to its solubility ; and 
as oxygen is more soluble in water than nitrogen, 
the air in solutKmin water lias not the gomposi- CHEMISTRY AND TOXICOLOGY. 
61 
tion 79 nitrogen to 21 oxygen, but 65 nitrogen to 
35 oxygen. 
(See carbonic anhydrid, Q. 828 et seq.). 
212. What compounds of nitrogen and hydroqen 
are known ? 
Ammonia, NH3 ; Hydrazin, N2H4; and Hydra- 
zoic acid, NSH. 
(See Manual, p. 105.) 
213. What are the physical properties of am- 
monia ? 
It is, under ordinary conditions of temperature 
and pressure, a colorless gas, having a pungent, 
irritating odor and a caustic taste. It dissolves 
lh 112(> to "The extent of 1.050 volumes to onejit 
0°, and is also very soluble in alcohol. 
214. Describe its cKemtcaCcFiafacters. 
It does not burn readily, but may be made to 
do so when mixed with O. It combines with 
XI20 to form a highly~alkaline liquid, containing 
ammonium hydroxid, JN|H4HU. It combines di- 
rectly with acids, without yepatation of hydrogen, 
to form amihflGiacal salts : 
Ammonia. 
NH, +~~HC1 = NH«C1 
Hydrochloric 
acyl. 
Ammonium 
ehlorid. 
(See ammonium compounds, Q. 549 et seq.). 
215 Give the formula and describe the relations 
of hydroxylamin. 
NHaHQ It is intermediate in composition be- 
tween ammonia, NBU, and ammonium hydroxid, 
NH4HO, and may~be considered as ammonia one 
of~Wtrose hydrogen atoms has been replacetTby 
hydroxyl, OH: thus, OII,HaN. It is consequently 
an amin. (See Q. 769, and Manual, pp. 105, 274.) 62 
ESSENTIALS OF 
216. What compounds of N and 0 are known ? 
Nitrogen monoxid N20 
rr" cTToxid NT) 
“ trioxid Jf2Os 
“ tetroxid NOi 
“ pentoxid 
217. By what other names is nitrogen monoxid 
known ? 
Nitrous oxid; laughing gas. 
218. By what method is it prepared? 
By heating ammonium nitrate to a temperature 
not exceeding 250° (482° F.), when it is gplltup 
into NoO and water—thus: 
(NH4)N03 = N20 -t- 2H20 
Ammonium 
nitrate. 
Nitrogen 
monoxid. 
Water, 
219. State some of the physical properties of 
NiO. 
It is a colorless, odorless gas, having a sweetish 
taste; heavier than air, sp. gr. 1.527; somewhat 
soluble in water, more so in alcohol. 
220. How does NtO rank as a supporter of com- 
bustion and respiration? 
After oxygen, it is the best we have; a glowing 
match-stick rekindles when' Immersed in the.gaa. 
as it does~in oxygen; pnosphorus and other cnin- 
bushble substances burn in N2U'witn almost as 
much hrilliancy as in oxygen, this being due to 
the fact that at the temperature produced N20 is 
decomposed into N and O, and in this mixture the 
O is in much larger proportion than in air. An 
animal will also live longer in an atmosphere of CHEMISTRY AND TOXICOLOGY. 
63 
NaO than in any other gas than air or oxygen ; 
but, although the supply of gas be maintained 
and the products of respiration bexeraayed, the 
animal eygntually dies of asphyxia.* 
221. What effect has'NjO upon the system when 
inhaled ? 
It produces, first, exhilaration, frequeptly ac- 
companied by laughter, and a tendency to mus- 
cular exertion, the patient sometimes becoming 
aggressive;' afterwards loss ot consciousness and 
complete anaesthesia. 
2221 What precautions are to he observed in the 
preparation of for use as an anaesthetic ? 
The temperature of the retort must not be 
allowed to rise beyond 250° (482° F.), lest the 
gas produced be contaminated with the higher 
oxids of nitrogen. The ammonium nitrate used 
should be absolutely free from ammnmumtihlo- 
rid. or the NaO will be contaminated with chlorin. 
223. By what other name is nitrogen dioxid 
known ? 
Nitric oxid. 
224. How is NO prepared ? 
By the actlon-of copper on nitripapid : 
8HNO3 + SCju = 2NO + 3Cu(NOs)a + 4IIaO 
Nitric 
acid. 
Copper. 
Nitrogen 
dioxid. 
Copper 
nitrate. 
Water. 
225. What are its physical properties ? 
A colorless -gas, sparingly soluble in water. 
Its taste and odor are unknown!"* 
\Vhat takes place when NO comes in con- 
tact with air or oxygen ? 
NO immediately unites with 0 to form NOa. 64 
ESSENTIALS OF 
227. What is another name for nitrogen tri- 
oxid ? 
Nitrous anhydrid ; improperly, nitrous acid. 
228.. Under what name is nitrogen tetroxid 
sometimes improperly designated ? 
Hyponitric acid. 
229. State its properties. 
It is a brown gas, having a disagreeable, suf- 
focating. odor : it is very irritating to the respi- 
ratory passages, colors the skin yellow, and is an 
energetic oxidizing 1 J ' 
280. How is njormea ? 
Whenever a metal, as copper, silver, or mer- 
cury, is dissolved in nitric acid, the acid is de- 
composed, as in Q. Gil ; the NO formed, as soon 
as it comes in contact with air, absorbs O and is 
converted into NUa. STfTlis gas is very delete- 
rious. care should be had that it have a tree exit 
into the open air whenever nitric acid is decom- 
posed, as in the formation of metallic 'nitrates' 
281. What is another name for nitrogen pent- 
oxid ? 
Nitric anhydrid. 
How many nitrogen acids are there, and 
what are they ? 
Three : 
Hvbonitrous acid—HNQ. 
Nitrous acid—HN02. 
Nitric acid— hnttt: 
233. Give the formula and basicity of nitric 
acid. 
HNOs. Monobasic. 
234. What is a common name for nitric acid? 
Aquafortis. CHEMISTRY AND TOXICOLOGY. 
65 
235. How does it exist in nature ? 
It exists in combination with the metals as 
nitrates. Those of potassium and sodium are 
the"niost abundant and are the chief sources of 
nitric acid. Ammonium nitrate occurs in small 
quantities in atmospheric air, especially after 
thunder showers* 
*7330. W/ldl is the principle of the manufacture 
of UNO, ? 
Sulfuric acid is caused to act upon potassium 
or sodium nitrate, when : 
kno3 + 1I3S04 = K1IS04 + hno3 
Potassium 
nitrate. 
Sulfuric 
acid. 
Mononotawsic 
sulfate. 
Nitric 
acid. 
237. What are the physical properties of pure 
nitric acid? 
A colorless liquid, having a penetrating odor 
and an intensely .sour taste. When cooled to 
—40° (—40J F.) it forms a solid. It boils at.863 
(186°.8 F.). ' 
238. State some of the chemical properties of 
UNOo. 
It has a strongly acid reaction. It acts ener- 
getically upon all_ animal tissues, decomposing 
them, and turnuig suph as contain "albuminoid 
subst&mcesyellow. It gives up part of its oxygen 
with great readiness, and is, power- 
f ul< ox-idizing'agent. It isTCMtly decomposed by 
most metals, with formation When 
exposed toaii; and ligfct, it and is 
decomposed into II20, and 0,_ 66 
ESSENTIALS OF 
289. Name and describe the varieties of HN03 
met with in commerce and pharmacy. 
Commercial: A yellow liquid, contaminated 
with the oxids of nitrogen, HC1, arsenic, and 
other impurities. It is met with in two degrees 
of st rength : Single aqua foriis = 39 per cent. 
HN03 ; and double aqua fgrtis — Of nor cent. 
HNOs. 
Fuming: A concentrated acid, containing 
much nitrogen tetroxid. which gives it a deep 
yellow' color.. It is a powerful oxidizing agent. 
Chemically pure (C. P.) acid: Perfectly color- 
less ; sp. gr. 1.521. Should be kept in bottles 
completely1 filled, and protected from the light. 
Acidum nitricum, U. S., Br., a colorless acid, 
of sp. gr. 1.42 = 70 per cent. HN03. 
Acidum nitricum dilutum, U. S.,, Br., the last- 
named diluted ; sp. gr. 1.059 = 10 per cent. 
HNO3, U. S.; sp. gr. 1.101 = 17.44 per cent., Br. 
240. Describe the tests for nitrates or HN03. 
1. Add an equal volume of H3SO4, cool, and 
float on the surface of the liquid a solution of 
ferrous sulfate ; the lower layer becomes grad- 
ually brown, black, or purple, beginning at the 
top. 
~2. Boil in a test tube some HC1 containing 
enough indigo-carmine to colordl blue, add the 
liquid to be tested, and boil again ; tlie color is 
discharged. 
8. If acid, neutralize with potassium hvdroxid. 
evaporate to drvness. moisten witlyjf h. ami 
add a crystal or brucin; a red color. 
4. Add H3SO4 and fragments of copper ; boil; 
brown fumes. (See Manual, pp. 110, 111.) CHEMISTRY AND TOXICOLOGY. 
67 
241. What is the appearance of stains upon the 
skin or mucous membrane caused by IIJV03 f 
Not red as with HC1 or II3SO4, but at first 
yellow, changing to dirty brownish-yellow. 
(Toxicology, see Q. ■ 
242. Give the symbol, and atomic and molecular 
weights of phosphorus. 
Symbol = P. Atomic weight = Jh Molecu- 
lar weight = 124. 
24o. Of how many atoms does the molecule of 
phosphorus consist ? 
Of four. 
244. How does phosphorus exist in nature ? 
It is not found in its own form, but is widely 
distributed in combination in the three king- 
doms of nature. In the animal it occurs both 
oxidized in the form of phosphates (the phospho- 
rus used in the arts is obtained from calcic phos- 
phate), as well as in certain organic compounds 
entering into the composition of nerve tissue. 
245. What is meant by allotropy ? 
as phosphorus and carbon, ex- 
ist in two or ipore forms, in which, although the 
chemical relations rtJIHiiin unaltered in kind, the 
physical properties vary ; these different condi- 
tions of the same element are said to be allotropic. 
246. In how many allotropic conditions does 
phosphorus exist, and what are they ? 
Four—black, white, red, and yellow. Of 
these, the last two hJe the most frequently met 
with. 
PHOSPHORUS. , 68 
ESSENTIALS OF 
247. What arc the physical properties of the or- 
dinary, or yellow, variety ? 
Wlien freshly prepared, and at ordinary tem- 
peratures, it forms a yellowish, translucent solid, 
which, on exposure to light, becomes more 
darkly colored and opaque. It has the consist- 
ence of wax. When exposed to the air it gives 
off white fumes and an odor of garlic. At 0° 
(32 F.) itrtlecomes brittle ; at 44° (111° F.) it 
melts to a yellowish liquid, and at 290° (554° F.), 
iiTtEeabsence o faifTls' con verted into a colorless 
vapor. In air, at 60° (140° E\), it ignites, burn- 
ing with a bright liame and giving off dense 
white fumes. Owing to the readiness with which 
Pignites, and the painful nature of the burns 
produced by it, it should never be cut except un- 
der HjO, and should not be handled except with 
forceps. In the, dark this form of P gives off 
a peculiar pale light It is insoluble in 1I20 ; 
sparingly soluble In alcohol, ether, and the fatty 
and ethereal oils ; very soluble in carbon disulfid, 
from which solution it separates in the formjjf 
crystals. 
'218. What are the physical properties of the red 
variety ? 
It is red, brown, or dark yellow in ccflor. It 
may be heated to 250° (482° F.) without melting, 
but at that temperature it is suddenly converted 
into the yellow variety, which ignites with an 
explosion. It fires much less readily than yellow 
phosphorus, and may be kept dry, while the yel- 
low must be preserved under HaO. It has no 
odor or taste, and is insoluble in those substances 
which dissolve the other form. CHEMISTRY AND TOXICOLOGY. 
69 
249. What is the most important difference be- 
tween the two forms ? 
The yellow variety is exceedingly poisonous, 
the red is innocuous. 
350. IIow may yellow phosphorus be pulver- 
ized ? 
By melting it under H,0, and agitating the 
mixture until it has cooled so far that, the 
phosphorus has solidified in a finely divided 
form. 
251. IIow is red Pprepared? 
By maintaining the yellow variety at from 
24<t (464 F.) to 280° (536° F.) in an atmosphere 
of carbon dioxid for two to three days, and, 
after cooling, washing out the unaltered yellow 
P with carbon disulfid. 
252. What are the chemical characters of phos- 
phorus ? 
It combines readily with oxygen (the yellow 
modification at lower temperatures than the red) 
to form an oxid if the oxygen be dry, or an acid 
in the presence of moisture. It combines di- 
rectly with Cl, gr, and L It is not acted on % 
HCl. or by cold 1I2S04. ' It is rapidly oxidized 
ft is an enenretic ■•e.l.mjn.r n.rpnl 
25oTIiow many varieties of phosphorus poison- 
ing may occur, and what are they ? 
Two. 1st, The acute form, consequent upon 
the ingestion of a poisonous dose of the ele- 
ment ; and 2d, The chronic form (also known 
as the lucifer disease), affecting those engaged 
in certain branches of match manufacture. 
254. IIow does the acute form occur? 
The recorded cases are about equally divided 70 
ESSENTIALS OF 
between accidental, suicidal, and murderous. 
The substances used being either match heads 
(which are composed, in the common sulfur 
match, of potassium chlorate, fine sand, phos- 
phorus, and a coloring matter), or a rat poison, 
which is a mixture of phosphorus with flour. 
255. What circumstances affect the rapidity with 
which symptoms appear in these cases ? 
The action is much accelerated by the pres- 
ence of any oily or fatty matter, which dissolves 
the poison and thus favors its absorption. The 
symptoms usually make their appearance within 
two or four hours after ingestion of the poison, 
but they may be delayed for days. 
256. Describe the prominent symptoms in acute 
phosphorus poisoning. 
Eructation of gas having the odor of garlic. 
The mouth, when observed in the dark, is fre- 
quently faintly luminous (phosphorescent). Af- 
ter several hours, pain in the throat, a sense of 
heat in the epigastrium, nausea, and vomiting. 
The vomited matters are sometimes bloody, and 
frequently (see Q. 261) luminous when agitated 
in the dark. The abdomen is tender, and there 
are diarrhoea and colicky pains. After one or 
two days these symptoms cease, there remaining 
only pain in the back and limbs and a feeble 
pulse. Death sometimes occurs suddenly in 
from two to four days. Usually about the fourth 
day the patient becomes jaundiced, suffers from 
headache, insomnia, and retention of urine, rap- 
idly becomes delirious and comatose, and dies. 
257. What is the lethal dose of phosphorus f 
The smallest quantity of P that has been CHEMISTRY AND TOXICOLOGY. 
71 
known to cause the death of an adult was 0.008 
gram (| grain). 
258. What treatment is to be followed1? 
The unabsorbed portion is to be removed as 
speedily as possible by an emetic of copper sul- 
fate, or the stomach pump. No chemical anti- 
dote is known. French oil of turpentine (the 
older the better) should be given as a physiologi- 
cal antidote. The food should be entirely free 
from oils and fats. 
259. What post-mortem appearances are ob- 
served after death by acute phosphorus poisoning? 
Occasionally small fragments of P may be 
detected, by their luminous appearance, in the 
stomach or intestines. The oesophagus, stom 
ach, and intestines are frequently marked with 
ecchymotic spots. Advanced fatty degenera- 
tion is observed in the liver, kidneys, heart, 
and muscular tissue. The blood is very fluid, 
and the red corpuscles more transparent than 
normal. 
260. Describe Mitscherlich's process for detecting 
phosphorus. 
This process is based upon the property of un- 
oxidized phosphorus of becoming luminous in 
the dark. The matters supposed to conTaTn~the 
poison are rendered fluid by dilution with water, 
and acidulated with sulfuric acid. They are 
placed in a flask upon a sand bath, and the flask 
connected with a Liebig’s condenser, which is 
placed in absolute darkness. Upon heating the 
flask any phospftorus'present is volatilized, and, 
condensing in the tube, forms a luminous ring. 
This reaction is very delicate, and the appearance 72 
ESSENTIALS OF 
of the ring is proof positive of the presence of 
unoxidized phosphorus. 
261. Under what conditions will this process fail ? 
The presence of certain volatile substances de- 
stroys the luminosity of phosphorus ; prominent 
among these are alcohol, ether, and oil of turpen- 
tine. In the case of the former two, which are 
quite volatile, the luminous ring does not appear 
until they have distilled over and are thus sepa- 
rated. When oil of turpentine is present the 
luminous property of phosphorus is permanent- 
ly destroyed; consequently, when it is known 
that this substance has been administered, this 
process should not be resorted to, and in any case 
only half the material should be used. 
(See Manual, pp. 114-117.) 
262. Give a short description of the process of 
match manufacture. 
The wooden splints are dipped for about a 
third of their length in some combustible sub- 
stance, as melted sulfur or paraffin ; after this 
has set they are pointed with the phosphorus 
paste. This paste is spread out on an iron plate, 
which is warmed. During the process (when the 
mixture does not fire, which frequently occurs) 
fumes of the lower oxids of phosphorus are given 
off. After the pointing process, the matches are 
arranged in the drying room, from which they 
are taken to be packed. 
263. What classes of operatives are liable to the 
lucifer disease ? 
Those who are engaged in the manufacture of 
phosphorus are not attacked by it, but those 
who are engaged in the pointing, drying, and CHEMISTRY AND TOXICOLOGY. 
packing of matches. Weak and scrofulous fe- 
males and children are more subject than others. 
264. How may this form of poisoning be dimin- 
ished in frequency, and prevented ? 
1st. Strict cleanliness and good ventilation of 
the shop are imperative. 2d. The mouth is fre- 
quently washed with a weak solution of sodic 
carbonate. 3d. Saucers filled with turpentine 
are placed in the rooms. There is only, one meth- 
od, however, of completely remedying the evil, 
and at the same time preventing the daily house- 
hold use of a violent poison—that is, the prohi- 
bition of the use of yellow phospTTonTs in the 
mn.nnfftrt.qrp of mnlrlipn 
265. What is the composition of gaseous hydro- 
gen phospliid ? 
P1I3. 
5TTTT7 How may it be prepared ? 
By the action of concentrated solution of 
caustic potash upon phosphorus, or by the de- 
composition of a compound "of phosphorus and 
calcium by wafer,. ' 
~2Wt. What are the properties of the gas as thus 
obtained ? 
It is colorless and has a disgusting odor of 
rotten Jjsfr ; almost insoluble"- m water, easily 
soluETe in alco'noi or etncr. As" each bubble of 
tlie~gas comes iii contact with the air it inflames 
and produces a ring of smoke. It is highly 
poisonous. * 
JjJgS. WTutrt other subsbmm- is prcs'dnt'tn the gas 
as thus obtained, and what property is due to its 
presence ? 
It is contaminated with small quantities of an- 74 
ESSENTIALS OF 
other compound of phosphorus and hydrogen, 
which is liquid at ordinary temperatures. It is 
to the presence of th4s substance that the gas 
owes the property of igniting on contact with air. 
The pure gas only ignites when heatecfto 100° 
(2LS1F.). 
269. How many compounds of phosphorus and 
chlorin arc known, and what are they ? 
Two: . 
Phosphorus trichlorid, P"'C13, 
[SftttT&cniorid. P'Clo. 
PCl:i is a colorless liquid, formed by the direct 
unioii of cliIoni)~~and phosphorus. When the, 
chlorin is in excess the solid PCUis formed. 
hiTT a oj phosphorus and oxy- 
gen are known ? 
Two : 
Phosphorus trioxid, P203, 
Phosphorus pentoxid, P205. 
271. Under what other name is P> 0., known, 
how is it formed, and what are its properties ? 
Phosphorous anhydride It is formed when 
phosphorus is oxidized in a very immea quanti- 
ty of perfectly dry air or oxygen. As soon as it 
is exposed to air containing a small quantity of 
moisture, it ignites from the heat produced by its 
union with H20, to form phosphorous acid. 
272. W hat is another name for PiOb, and how 
is it formed f 
Phosphoric anhydrid. It is formed when 
phosphorus is burned in dry air or oxygen. 
273. What are its properties? 
It is a snowy-wliite, flocculent powder, having CHEMISTRY AND TOXICOLOGY. 
75 
a tendency to unite with water, which it absorbs 
from other substances greedily (owing to this 
property it forms a valuable drying agent), form- 
ing a highly acid liquid. . 
"274. Give the names and formula of the acids 
containing phosphorus. 
Ilypophosphorous acid, Ij^PO,: Phosphorous 
acid, H3PO3; Phosphoric acid, H3P<)4 ; Pyro- 
phosphoric acid, H4P207 ; Metaphosphoric acid, 
IIP03. 
275. What are the basicities of these acids ? 
Ilypophosphorous acid is monobasic ; phos- 
phorous acid, dibasic ; phosphoric, tribasic ; py- 
rophosphoric, tetrabasic; and metaphosphoric, 
monobasic. 
276. Write the formula of the sodium {univalent) 
salts of the phosphorus acids. 
NaipP02; NaiPPOs; Na2HP03 ; NaII2P04; 
Na2IIP04 ; Na3P04; NaiPP.O, ; Na2H2P207; 
Na3HP207: Na4P2()7 ; NaP03. 
277. How does phosphoric acid occur in na- 
ture ? 
It is not found free, but is very widely dissemi- 
nated in combination in the phosphates, in the 
mineral, vegetable, and animal world. 
278. By what other names is it known ? 
Common phosphoric acid or tribasic phosphoric 
acid. 
279. How is it prepared ? 
By the direct oxidation of P by means of 
HN03. The reaction,, which is dangerous when 
yellow P is used, is started by the application of 
heat, and, once started, continues without fur- 
ther heating. 76 
ESSENTIALS OP 
280. What is the Acidum phosphoricum dilu- 
tum, U. 8., Br. ? 
A solution of phosphoric acid, prepared as 
above, diluted with water to sp.gr. 1.056, and 
containing 10 per cent, of acid, U. S. ; sp. gr. 
1.08 = 14 per cent, of acid, Br. 
281. By what tests may phosphoric acid or a 
phosphate in solution be detected ? 
1. Add solution of ammonium chlorid, contain- 
ing free ammonia, and then solution of mag- 
nesium sulfate ; if II3P04 be prescnC~a white 
crystalline precipitate is formed 
[The same reaction occurs if an arsenate be 
.present.] 
2. To the neutral solution add solution of sil- 
ver nitrate ; if H3P04 be present, a yellowish- 
white precipitate is formed, which dissolves on 
addition of HN03 or of ammonium hydroxid. 
[If the precipitate were formed by anjjxscuate, 
it would not be yellowish, but brown or brick 
red.] 
3. To dilute ITN03, add the solution to be 
tested, and then solution of ammonium molyb- 
date ; if II3P04 be present, a yellowish precipi 
tate is formed. 
282 Give the symbol, and atomic and molecular 
weights of arsenic. 
Symbol = As. Atomic weight — 75. Mole- 
cular weight = 300. 
283. 0/ how many atoms is the molecule of ar- 
senic composed f 
Of four. 
AKSENTC. CHEMisTKy And toxicology. 
77 
284. How does arsenic exist in nature ? 
In small quantities in the elementary form ; 
more abundantly in three sulfur compounds, 
realgar, orpiment, and mispickel, the last being 
a compound of sulfur, arsenic, andiron, and the 
chief (ire of arsenic. It also exists in small quan- 
tifies in many ofes, and in traces in the waters of 
certain mineral springs* 
285. Wliat are (Tie;'properties of arsenic ? 
It is a gray solid. When pure it is odorless 
and tAStGlessj'easily powdered ; sp. gr. 5.6 to 
5.9 ; when heated to 180° (356° F.) without ac- 
cess of air, it distils unchanged and without melt- 
ing. It is a good conductor of electricity. 
286. ’"Whataction have air and water upon As? 
At ordinary temperatures it remains unchanged 
in dry air ; at High temperatures it unites rapidly 
wi't’h O, producing a strong bluish-white light. 
When pure it is insoluble in H2Q, but when ex- 
posed to that fluid or to damp air it becomes tar- 
nished from the formation of a film of oxid upon 
its surface, and this oxid is dissolved to a certain 
extent by the HaO. 
287. For what purposes is arsenic used in the arts? 
It is mixed with lead in the manufacture of 
shot : it enters ifffo the'comoosi t.j'ui nf 11 y 
andis used in certain fireworks. \ 
“"288. What compound of arsenic mud hydrogen 
is known ? 
Hydrogen arsenid, AsH3. 
289. Tinder what conditions is this substance 
formed ? 
Wheii nascent hydrogen is in prgsepce of an 
arsenical compound., 78 
ESSENTIALS OP 
290. What are its physical properties ? 
A colorless iras. having a strong odor of garlic, 
soluble liTtfve volumes of air free II20 ; burns in 
air. 
291. How is it affected by red heat in the absence 
of air ? 
It is decomposed into its constituent elements. 
As being deposited asia brilliant metallic solid 
;im! IT passing oil as gas. 
''Z'Xt What is produced when Aslh is burnt in 
air ? 
If the flame be not interfered with, the com- 
bustion is complete, the H forming HaO, and the 
As, As203. The latter may be condensed on a 
cold surface held above the flame, in the form of 
white octahedral crystals. 
If the flame be cooled by introduction into it of 
a cold surface, the oxidation is limited to ihe 
formation of H20, and elementary As is deposited 
upon the cold surface as a brown, or dark gray, 
film. 
293. What changes are caused by passing Aslh 
through a sohition of silver nitrate ? 
The solution is darkened, and deposits a black 
sediment of metallic silver. Arsenious acid is 
produced, and remains in the solution,^ 
294. Name the compounds of arsenic and oxygen . 
Arsenic trioxid, As2Os. 
Arsenic pentoxid, As206. 
295. Under what other names is arsenic trioxid 
known f 
Arsenious anliydrid, white arsenic, and, im- CHEMISTRY AND TOXICOLOGY. 
79 
properly, as arsenious acid ; Acidum arseniosum, 
U. S., Br. 
296. What are the physical properties of As2 03 ? 
It occurs in two forms : 1st. As “Ikn^iiti-of 
arsenic,” a heavy, white, crystalline powder, 
usually in octahedra, sometimes in prisms ; sp. 
gr. 3.69. 2d.» An amornhons substance, either 
translucent and yellowish (vitreous arsenic) or 
white and opaque (pcrrcelainous arsenic); sp. gr. 
3.79. Both forms are odorless and have a faint, 
somewhat metallic taste whenjn solutioh. 
297. Describe and explain what is ooserved when 
powdered white arsenic is thrown on water. 
Notwithstanding its high sp. gr., a portion 
only sinks, the remainder floating on the surface. 
The particles of the portion which sinks are no 
longer distinct, but are collected in lumps, each 
of which encloses a bubble of air. The floating 
particles also have air bubbles adherent to them. 
A fllm of air therefore adheres to the surface of 
the arsenic and prevents its contact with the 
water. 
298. What is the solubility of white arsenic in 
pure water ? 
The vitreous variety is more readily and more 
rapidly soluble than the crystalline, but by pro- 
longed boiling the solubilities of the two be- 
come more nearly equal. Even after long con- 
tact with a large excess of cold H20 all of the 
crystalline arsenic, is not dissolved. One thou- 
sand parts of cold H20, in contact with powdered 
white arsenic for f "™ntiy-fr>"-11 hours, dissolve 
about two parts of the oxid. The same amount 
of boiling II20, put upon the powder and allowed 80 
ESSENTIALS OF 
to stand twenty-four hours, dissolves about 10 
parts, and the same amount of H20, boiled on 
the powder for one hour (the amount of liquid 
being kept the same), dissolves about 65 parts. 
A hot saturated solution may be evaporated to 
half its bulk without depositing any of the oxid, 
and, if allowed to cool, it still retains a large 
amount. 
299. How is the solubility of white arsenic in 
water influenced by the presence of other substances? 
The presence of mineral acids, or alkalies, 
ammonia, ammoniaeaTBillCS',"alkaline carbonates, 
tartaric acid, or tartrates increases thejsoluhility. 
Fats arid other organic substances (present in the 
various liquid articles of food) diminish the solu- 
bility. 
Note.—In medico-legal cases it must not be forgotten 
that a poisonous substance may be swallowed witfi a 
drink, without being in solution. If the beverage lie mu- 
cilaginous, or be stirred immediately before drinking, 
the amount held in suspension may greatly exceed that 
held in solution. ———— 
300. If As-. 03 be heated in a tube, what occurs? 
It volatilizes unchanged, and is deposited in 
the cool parts, of the tube in the form of small, 
brilliant, white, eight-sided crystals. 
301. If As, Os be heated in the presence of char- 
coal, what occurs? 
It gives up its oxygen readily ; carbonic an- 
liydrid is formed, while arsenic is deposited in 
the elementary form. 
302. IIow does As203 behave with oxidizing 
agents ? 
It takes up oxygen readily. In aqueous solu- CHEMISTRY AND TOXICOLOGY. 
81 
tion, exposed to the air, a portion is converted 
into H3As04. With IIN03 the action is more 
rapid, II3ASO4 being formed,while brown fumes 
are given off. 
303. What action has hydrogen sulfid on As-iO* 
in acid solution ? 
Both substances are decomposed, the trisulfld 
of arsenic, As2S3, being deposited as an insolqble 
yellow powder, 
304. For what purposes is As? 0., used in the arts ? 
In the manufacture of green pigments; of 
white' glass ; in calico printing : ~in the 
preservation of animal substances by the taxi- 
tlermist and fgr dissection ; as a vermin poison; 
and as the starting-point in the manufacture of 
arsenical compounds. 
305. What is tfiPtrue arsenious acid ? 
This substance has not been isolated, but is 
considered as existing in solutions'of arsenious 
anhydrid, and having the formula 1I3As03 
(corresponding to that of phosphorous acid). 
There are, a number of‘important 
salts corresponding to this acid, known as ar- 
senites. 
' What is produced when a solution of sodium 
carbonate is heated with white arsenic ? 
A solution of sodium arsenite. Carbon di- 
oxid is given off]: 
2Na2C03 + As203 -t- tT20 — 
Sodium 
carbonate. 
Arsenic 
trioxid. 
Water 
= 2Na2IIAs03 + 2C02 
Disodic 
arsenite. 
Carbon 
d^oatid. 82 
ESSENTIALS OF 
307. What is Fowler’s solution ? 
A solution of potassium arsenite in water, con- 
taining compound tincture of lavender to give 
it taste and odor, that it may not be mistaken for 
water. 
308. What is Scheele’s green ? 
Arsenite of copper. 
309. What is Schweinfurt green f 
A compound of arsenite and acetate of copper; 
aceto-metarsenite of copper. 
310. Under what name is Schweinfurt green 
known in the U. S.f 
Paris green. 
311. What is anotherpiame for arsenic pentoxid, 
and what are its properties ? 
Ajgenic anhydrid. It is a heavy, white solid, 
gradually hut abundantly soluble in water. 
312. What is produced w7ien'~As70l is dissolved 
in 11,0? 
An acid solution of arsenic acid, H3AsQ4. 
313"."1 WfdW phosphorus acid does arsenic acid re- 
semble in its chemical properties ? 
Phosphoric acid. It is converted into pyroar- 
senic and metarsenic acids under the same condi- 
tions under which phosphoric acid yields pyro- 
phosphoric and metaphosphoric acids. Its salts, 
called arsenates, resemble in constitution the cor- 
responding compounds of phosphoric acid. 
31?. What is realgar, and how does it occur ? 
Arsenic, djjsijlfid, As.,S„ It is found in nature 
in translucent red crystals. It is also manufac- 
tured commercially by melting together arsenic 
trioxid and sulfur; and, thus prepared, it forms 
dark-reel amorphous masses, tasteless and odor- CHEMISTRY AND TOXICOLOGY. 
83 
leas. In powder it is orange-yellow, insoluble in 
water, alcohol, or dilute hydrochloric acid. 
315. Hmc do the natural and artificial realgars 
differ in their action when taken internally, and 
why ? 
The native realgar is inert, while the artifi- 
cial product is poisonous. The sulfid is in both 
cases non-poisonous, but the artificial realgar al- 
ways contains arsenic trioxid* 
316. What is the common name for arsenic tri- 
sulfid, and how does it occur ? 
It is found in nature as brilliant, yellow, gold- 
like scales and crystals, known as arpiment. ft 
is also manufactured artificially by subliming to- 
gether arsenic trioxid and sulfur; this product, 
used as a pigment under the name King’s yellow, 
always contains arsenic trioxid, which rentiers it 
more poisonous than orpiment. Pure As2S3 may 
be obtained by passing hydrogen sulfid through 
an acid solution of arsenic trioxid and washing 
the deposit. * 
317. What relation has As3S3 to As303 chemi- 
cally ? 
As Asa03 is the anliydrid of arsenious acid, so 
As2S3 is the anhydrid of an acid of similar com- 
position, in which the oxygen is replaced by sul- 
fur, called thioarsenious acid, AsS3H3, and corre- 
sponding to which are salts, called tliioarseuites. 
318. What other compound of sulfur and arsenic 
is known ? 
Arsenic pentasulfid, As2S6. 
31$). What is Donovan’s solution ? 
A solution of m ercuric iodid and arsenious 
iodid, Asl3. " 84 
ESSENTIALS OF 
320. Name some of the compounds of arsenic 
which have given rise to poisoning. 
Elementary arsenic, hydrogen arseuid, arsenic 
trioxid, potassium or sodium arsenite, artificial 
sulfids of arsenic, arsenical greens. 
321. In what way may elementary arsenic cause 
poisoning ? 
By the ingestion of flypaper, or the ll30 in 
which it has-been moistened. The As with which 
the paper is charged is converted into II3A8O3 by 
the action of air and moisture. 
322. How has As If caused poisoning ? 
By inhalation of 11 made from Z11 and II2SO4 
containing As. 
323. Which of the arsenical compounds has been 
the most frequently administered, with homicidal 
intent ? 
Arsenic trioxid. 
324. By what channels has it been so adminis- 
tered ? 
By the mouth, by injection into the rectum and 
into the male urethra, by the vagina. 
325. Have fatal cases of arsenical poisoning re- 
sulted from the external application of arsenical 
compounds t 
Yes, numerous cases are recorded resulting 
from the rubbing of arsenical preparations into 
the scalp, scrotum, etc., to kill parasites, as well 
as by the use of such preparations by quacks as 
cancer cures. 
32(5. What is the lethal dose of white arsenic ? 
The smallest amount known to have caused 
the death of an adult was 0.162 gram (2* grains). CHEMISTRY AND TOXICOLOGY. 
85 
A case is recorded in which 62 grams ( § ij.) were 
taken without causing death. 
327. State the conditions which favor the activ- 
ity of the true poisons. 
1 When taken in solution, or in a form readily 
dissolved by'The gastTRT secretions. 2. When 
vomiting does not occur, or is delayed. 3. When 
taken into the empty stomach with little or no 
solid food. 4. When the person exercises aclive- 
ly after the poison has been taken, 5. When 
taken into a system already weakened by disease. 
328. State the conditions which impede the action 
of the true poisons. 
1. When taken in a form insoluble either by 
reason of chemical combination or physical con- 
dition. 2. When vomiting is copious and occurs 
early. Almost the entire quantity taken may be 
thus expelled before absorption has occurred to 
any great extent. 3. Sleep. 4. When taken by 
a person already under the influence of a drug 
having antagonistic action. 5. When taken by 
one habituated to its use. 
329 In what way may the arsenical pigments 
give rise to accidental poisoning f 
By inhabiting rooms the walls of which are 
covered with paper colored by these substances ; 
by the use of articles of clothing or ornament 
dyed with them ; by sucking ornamental con- 
fectionery of a green color ; and by the acci- 
dental mixing of Paris green, used to exterminate 
vermin, with articles.,of food. 
~~V>oW. What are the prominent symptoms of acute 
arsenical poisoning ? 
They usually begin in from 20 to 45 minutes, 86 
ESSENTIALS OF 
Nausea and faintness. Violent, burning pain in 
tiie stomach, which becomes more and more 
intense, and increases on pressure. Persistent 
and distressing vomiting of matters, sometimes 
brown or gray, or streaked with blood, or green 
(Paris green), or black or blue (charcoal or indigo 
powder mixed with As203 according to the Eng- 
lish law). Purging. More or less severe cramps 
in the lower extremities. 
331. What are the prominent symptoms of 
chronic arsenical poisoning ? 
Inflammation of the conjunctivas, with intole- 
rance of light. Irritation of the skin, accompa- 
nied by an eruption (eczema arsenicale). Local 
paralyses. Great weakness and emaciation. Ex- 
foliation of the cuticle and falling out of the 
hair. 
332. What should the treatment be in acute 
arsenical poisoning ? 
If vomiting have not occurred, it should be 
induced by tickling the fauces or by zinc sulfate, 
never by tartar emetic ; the stomach pump should 
be used if the case be seen early. Moist, recently 
prepared ferric hydroxid, or “dialyzed iron,” 
should be administered. 
333. 1low is ferric hydroxid prepared for this 
purpose ? 
Add to solution of ferric sulfate (Liq. ferri 
tersulfatis, U. S. ; Liq. ferri persulfatis, Br.) 
excess of aqua ammonite, collect upon muslin, 
and wash with water. It should be prepared 
when wan ted, and administered, while still moist, 
in doses twenty times as great as the amount of 
arsenic'presumed to have been taken. ~ ’ CHEMISTRY AND TOXICOLOGY. 
87 
334. What tent .should be applied to the urine 
during life to detect the presence of arsenic ? 
Reinsch’s test (see Q 346-348). 
335. When should this test not be used, and whyf 
It should not be applied to any portion of the 
body after death in a case of suspected homi- 
cide, until the presence of arsenic has been 
demonstrated by other tests, anduntil after 
the relative amounts of As and Cu have Been* de- 
termined. If this precaution be neglected, Cu is 
introduced into the substances uhaer*examina- 
tion, and between As’20:i and 
Paris green becomes impossible. 
336. Describe the post-mortem appearances in 
acute arsenical poisoning. 
They are confined to the stomach and intes- 
tines. The stomach is inflamed, whether As has 
been taken by the mouth or by other channels 
of absorption. The mucous surface is coated 
with a layer of mucus, tinged with blood or bile, 
and sometimes containing white crystals of 
As20;) or green particles of Paris green. The 
color of the mucous membrane is brownish red, 
interspersed with darker streaks or patches be- 
tween the rugae. The small intestines are some- 
times inflamed throughout their length, but 
more usually the inflammation is limited to the 
duodenum. 
337. Is the above appearance of the stomach posi- 
tive proof that the poison was taken during life ? 
It is not. When As203 is injected into the 
stomach after death, the walls of the viscus be- 
come reddened so as closely to simulate the 
appearance of inflammation. 88 
ESSENTIALS OF 
338. What portions of the cadaver should be 
preserved for analysis in cases of suspected homi- 
cide by poison ? 
The alimentary canal from the cardia to the 
middle of the rectum, unopened, and the con- 
tents enclosed by ligatures at the oesophagus, 
duodenum, and lower end of gut; the liver, in- 
cluding the gall bladder ; one kidney ; the spleen ; 
a piece of muscular tissue ; the brain, and any 
urine which may remain in the bladder. 
Any suspected food articles, and any obtain- 
able vomited matter, are to be also preserved. 
339. How should these parts be preserved? 
They are to be placed in clean and new glass 
jars, closed with glass or cork covers or stoppers. 
Jars with metallic caps should never be used. 
Tapes or cords should be tied about the jar and 
cap, to which they should be attached by seal 
ing wax bearing impressions of a seal, in such 
a manner that access can only be had to the 
interior after breaking the seals or cutting the 
tapes or cords. Great care must be exercised 
that no sealing wax can get into the jars. Each 
portion should be placed in a jar by itself. 
340. What should be particularly noted in ex- 
amining the cadaver superficially ? 
The presence or absence of incisions of the 
course of the arteries, particularly brachials, 
femorals, and carotids, as indicating whether or 
no the body has been embalmed. 
341. How may solutions of arsenious and ar- 
senic acids be distinguished from each other ? 
By solution of nitrate of silver, in presence 
of ammonia. With solution of arsenious acid CHEMISTRY AND TOXICOLOGY. 
89 
silver arsenite is formed as a yellow precipitate, 
wliile with solution of arsenic acid silver arsen- 
ite is formed as a chocolate-brown precipitate. 
343. Upon what reactions is Marsh’s test for ar- 
senic based? 
1. When nascent II is formed in presence of 
an arsenical compound, AsH3 is produced. 
2. When AsH3 is passed through a red-hot 
tube, it is decomposed into As and H. 
3. When AsII3 is burned, and a cold surface 
held above the flame, As203 is deposited in octa- 
hedral crystals. 
4. When AsII3 is burned, and a cold surface 
held in the flame, As is deposited as a brown or 
black stain. 
5. When AsH3 is passed into a solution of 
silver nitrate, metallic Ag is deposited and the 
solution contains H3AsOa. 
6. When As is heated in a current of air, it dis- 
appears and octahedral crystals of As203 are 
formed. 
(See Manual, pp 133-135.) 
343. What substance maybe mistaken for arsen- 
ic by this test ? 
Antimony, which under the same conditions 
produces stains and mirrors closely resembling 
those of arsenic. 
344. IIow may the two substances be distin- 
guished ? 
By gently heating the deposit in one of the 
tubes, when it disappears rapidly, and octahedral 
crystals are formed if it be As. 
It requires a higher degree of heat to cause the 
disappearance of the antimonial deposit, and the 90 
white sublimate into which it is converted is not 
crystalline. 
(See Manual, p. 1134.) 
345. Describe Reinsch's test for arsenic. 
Add to the suspected fluid one-sixth its volume 
of pure hydrochloric acid ; suspend in the fluid 
a piece of bright electrotype copper, and boil. 
If a steel-gray deposit form on the copper, re- 
move the copper with its adhering deposit, wash 
it with pure water, and dry between folds of fil- 
ter paper, being careful not to rub off the deposit. 
Coil up the copper and put it into a clean, dry 
tube, open at both ends, holding the tube at such 
an angle that the spiral does not slip out ; apply 
heat at the part containing the copper. 
346. What other substances produce deposits 
similar to those of arsenic, and how may they be 
distinguished ? 
Antimony, mercury, bismuth, gold, and pla- 
tinum. If either of these be present, a gray or 
black deposit is formed on the copper. If the 
deposit be arsenic, there will form in the cold 
part of the tube, during heating of the part con- 
taining the copper, a white deposit, composed 
of small octahedral crystals of arsenic trioxid ; if 
antimony, a white sublimate will form, which 
is either entirely amorphous, or amorphous for 
the most part, containing a few crystals, either 
octahedra, not so brilliant as those of As203 and 
nearer to the heat, or prisms in that part of the 
tube which was in the flame; if bismuth, pla- 
tinum, or gold, no sublimate will be formed ; and 
if mercury, there will form a deposit of metallic 
mercury in small, brilliant globules. 
ESSENTIALS OF CHEMISTRY AND TOXICOLOGY. 
91 
347. What precautions are to be observed in this 
test ? 
Be sure of the purity of the copper and hy- 
drochloric acid used ; perform a blank testing 
with samples of the hydrochloric acid, copper, 
and water, under the same conditions as the actual 
test. Use only a small piece of copper at the 
beginning ; when a deposit has formed on that, 
remove it and substitute another, and so on until 
all the arsenic present has been collected. 
348. W hen is Reiascii's test not applicable ? 
When arsenic is present in the form of arsenic 
acid or an arsenate ; in this case the deposit is 
formed but slowly, if at all. When it is suspected 
that the substance present is an arsenate, it 
should be reduced to an arsenite by sulfurous 
acid before applying Reinsch’s test. The test 
cannot be applied in the presence of oxidizing 
agents, such as free nitric acid, potassium chlo- 
rate, nitrates in large quantity, etc. On the 
other hand, this test is the only one that can 
be applied directly to fluids containing organic 
matter. 
Note.—In testing the urine it may safely be considered 
that if arsenic he present it will be as arsenite and not as 
arsenate. 
849. What reaction takes place when Ifi8 is 
passed through alkaline and acid solutions of 
arsenious acid or the arsenites ? 
If the solution be alkaline it becomes yellow ; 
if acid, a precipitate of yellow arsenic trisulfid is 
formed. 92 
ESSENTIALS OF 
350. What reaction occurs when a cold solution 
of an arsenate is treated icith JLiS ? 
The arsenate is first reduced to arsonite, with 
deposition of sulfur ; subsequently the yellow 
precipitate of As2S3 is slowly formed. The com- 
plete separation of the As in this case requires 
several days. 
351. Describe the reduction test/hr arsenic. 
Place the solid to be examined in the closed 
end of a small tube, and above it a fragment of 
charcoal ; heat the charcoal to redness and then 
heat the solid under it. In the presence of As 
a brilliant metallic “mirror” is formed in the 
tube. The materials and tube must be perfectly 
dry. 
352. Describe the sublimation test for As-i 03 and 
Paris green. 
Heat the suspected powder in a small tube 
closed at one end ; crystals of As.jOa are formed 
in the cool part of the tube. 
353. Describe the copper test for arsenic. 
Add solution of cupric sulfate, to which am- 
monium hydroxid has been added until the pre- 
cipitate formed just redissolves, to the suspected 
liquid ; a green precipitate is formed if the re- 
action be neutral. 
354. What treatment must organic fluids be sub- 
jected to before testing for mineral poisons? 
The organic matter must be destroyed, as it 
interferes with the reactions to such an extent 
that, in fluids containing organic matter, it is 
impossible to be certain of the presence or ab- 
sence of poisonous mineral matter. (See Manual, 
p. 136.) CHEMISTRY AND TOXICOLOGY. 
93 
ANTIMONY. 
355. What are the symbol and atomic weight of 
antimony ? 
Symbol = Sb (from the Latin: Stibium). 
Atomic weight = 120. 
356. What are its physical properties ? 
It has a metallic appearance, crystalline tex- 
ture, is tasteless, odorless, brittle, and easily pul- 
verized ; it melts at 450° (842° F.), and crystallizes 
on cooling ; it may be distilled unchanged when 
air is excluded, but when sufficiently heated in 
air it burns brilliantly. 
357. What is the chief ore of antimony? 
The trisulfid, Sb2S3, known commercially as 
black antimony or crude antimony, and pharma- 
ceutically as Antimonii sulfldum, U. S. ; Anti- 
monium nigrum, Hr. 
358. For ichat purposes is antimony used in the 
arts ? 
It enters into the composition of a number of 
important alloys : type metal is an alloy of lead, 
tin, and antimony; britannia metal and the va- 
rious antifriction alloys contain antimony. Its 
value in these alloys is, that it renders them hard 
and communicates the property of expanding 
on solidifying. 
359. What compound of antimony and hydrogen 
is known, and what are its properties ? 
Hydrogen antimonid, or antimoniuretted hy- 
drogen, SbII3, having a composition correspond- 
ing to the hydrogen compounds of nitrogen, 
phosphorus, arwl arsenic. It is gas, 
resembling hydrogen arsenidin itsfproperties and 94 
ESSENTIALS OF 
decompositions, except in that it is but slightly 
poisonous. 
360. What is butter of antimony, and what are 
its physical properties ? 
It is the trichlorid, SbCl3, and forms at ordi- 
nary temperatures a semi-solid, yellow, crystal- 
line mass, which fuses at 73° (164° F.), and boils 
at 223" (433°.4 F.). When exposed to the air it 
absorbs moisture and becomes first cloudy, then 
dark and oily. 
361. What is the action of IfO upon antimony 
trichlorid ? 
When diluted with H20 it is decomposed, and 
a white, insoluble precipitate is formed. This 
was formerly known as powder of Alga,roth, and 
is an oxychlorid of antimony. 
362. How is the Antimonii oxidum, U.S.,Br., 
prepared, and what is its composition ? 
By decomposing the oxychlorid, obtained by 
the reaction given in 361. It is the trioxid, 
Sb203. 
363. What substance is foi'med when hydrogen 
sulfid is passed, through a solution of an antimo- 
nial compound ? 
Antimony pentasulfid, Sb2S6. This is the 
“ golden sulfuret of antimony.” It is an orange- 
colored, amorphous powder, readily soluble in 
ammonium sulfhydrate solution and in hot HC1, 
but insoluble in ammonium hydroxid solution. 
364. What is Kermes mineral ? 
A mixture, in varying proportions, of the sulf- 
ids and trioxid of antimony. (See Q. 929, 930.) 
(For analytical reactions of Sb see Manual, pp. 
134, 141 ; and Laboratory Guide, pp. 18, 86.) CHEMISTRY AND TOXICOLOGY. 
BORON. 
365. What are the symbol, atomic weight, and 
valence of baron ? 
Its svmlTol is B ; its atomic weight, _11, It is 
trivalent in all of its compounds. 
366. What is the most important compound of 
boron ? 
Boric acid—H3BQ3—Acidum boricum. U. S. 
L 367. What are tVe properties of borne acid ? 
White, glistening plates, unctuous to the touch; 
odorless ; having a slightly bitter taste, and with- 
out corrosive or poisonous action ; soluble in 
water. It is a valuableautiseptic. When heated 
to 80° (176° F.) it loses H20 and fornls metaboric 
acid, HB03 ; and at 100° (212° F.) it'forms pyro- 
boric acid, H2B4O7, whose sodium salt is borax. 96 
ESSENTIALS OP 
GROUP V. CARBON GROUP, 
Carbon C 12. 
Silicon Si 28. 
368. State the common characters of the dements 
of this group. 
They are bivalent and quadrivalent. They are 
combustjbler Each exists in three allotronic 
form’” Their saturated oxids are 
dibasic acids. 
CARBON. 
369. What are the symbol and atomic weight of 
carbon ? 
Its symbol is C. and its atomic weight is .12, 
370. How does carbon exist uncombined in 
nature ? 
1. Almost pure, crystallized, as diamond. 
2. Nearly pure, but less so than in diamond, as 
graphite or " black lead.” 3. Mixed with more 
or less impurity, as the various kinds of coal. 
371. Name some of the artificial products com- 
posed almost entirely' of carbon. 
"~1. Charcoal, obtained by subjecting wood to 
heat,"Tritint limited supply of air. 2. Lairnr 
bTitck, obtained by the incomplete of 
suTjstances rich in carbon, such as resin, natural CHEMISTRY AND TOXICOLOGY. 
97 
gas, etc. 3. Coke, a porous substance remaining 
after beating certain kinds of coal withobtron- 
tact witji air. 4. Animal Charcoal, obtained" by 
subjecting animal matter to beat in closed ves- 
sels ; contains a large amount of mineral salts or 
ash. 
"372. State the properties and uses of animal 
charcoal. 
It possesses the power of absorbing coloring 
matters and other substances from solutions. It 
isTisecT in the refining of cane-sugar to remove the 
coloring mattefTahd for the same purpose in va- 
rious pharmaceutical and chemical operations. 
Care must be had, however, that loss be not 
sustained from the absorbing action of the char- 
coal on other substances, such as the alkaloids 
and various vegetable principles. Indeed, puri- 
fied animal charcoal has been used to separate 
alkaloids from solutions in which they are mixed 
with other substances. The deodorizing power 
of the crude charcoal is greater than that of the 
purified. The latter is to be used in the presence 
of any substance capable of acting on the mineral 
ingredients of the crude charcoal, notably in the 
presence of acids. (See Q. 578.) 
373. What is the action of oxygen upon carbon 
at high temperatures ? 
The two elements have a great tendency to 
unite with each other, with liberation of heat and 
light. If the supply of O be sufficient, an invis- 
ible compound, having the composition COa, is 
formed ; while if the supply j)f Q be insufficient, 
another gas, CO, is formed^ 98 
ESSENTIALS OF 
374. I\hat are the compounds of carbon with 
other elements called ? 
Organic substances. 
(For Compounds of Carbon, see p. 171 et 
seq.) 
SILICON 
375. What are the symbol and atomic weight of 
silicon ? 
Its symbol is Si; its atomic weight 28. 
376. Name some important compounds of sili- 
con. 
• Silicic anhydrid, or silicon dioxid, Si02, and 
the corresponding acid, H4Si04 
377. How do these substances exist in nature ? 
They are very abundant. Silicic anhydrid ex- 
ists nearly pure as rock crystal, and less pure in 
the quartz entering into the composition of vari- 
ous rocks, sand, sandstone, and in a vast number 
of minerals. Silicic acid in combination, i.e., 
silicates, constitutes a great number of minerals, 
and exists in animal and vegetable bodies and in 
many mineral waters. CHEMISTIiY AND TOXICOLOGY. 
99 
CLASS III. AMPHOTEKIC ELE- 
MENTS. 
378. What are the characteristics of the ampho- 
teric elements ? 
Their oxids combine with water, sometimes to 
form acids. sometimes to form bases. They are 
capabltTof displacing the TycTrogen of the oxy- 
acidaJjj form_px£Salts. 
379. What name is used to designate the elements 
of this and the following class? 
4"“W?T&.etals. 
380. Name the principal amphoteric elements': 
Gold, chromium, manganese, iron, aluminium, 
lead, bismuth, tin, and platinum. 
GROUP I. THE GOLD GROUP. 
381. What are the symbol and valence of gold? 
Au, from the Latin, aurum. Gold forms two 
series of compounds, in one of which it is uni- 
valent, as in aurous chlorid, AuCl, and in the 
other trivalent, as in auric chlorid, AuCL. 
382. By what agents is gold attached ? 
By free chlorin or bromin, by nitro-muriatic 
acid, from which chlorin is liberated. Mercury 
dissolves gold, forming a liquid amalgam. It is 
not attacked by any single acid or by any alkali. 
gold. Au. 197. 100 
ESSENTIALS OF 
383. What is the composition of United States 
gold coin ? 
900 parts of gold, alloyed with 100 of copper. 
Jeweller’s gold (18 karat) contains about foV'o 
gold, the remainder being copper and silver in 
proportions varying with the color. 
384. W hat compound of gold is used in the chem - 
ical and histological laboratories ? 
Auric chlorid, AuCls = terchlorid of gold. 
385. Give the tests for the auric compounds. 
1. With H28, in neutral or acid solution, a 
dark-brown precipitate, insoluble in HNOs or in 
nh4hs. 
2. With stannous chlorid and a little chlorin 
water, a purple-red precipitate. 
3. With ferrous sulfate, a dark-brown precipi- 
tate. CHEMISTRY AND TOXICOLOGY. 
101 
GROUP II. THE IRON GROUP. 
Chromium Cr 52. 
Manganese Mn 54. 
Ikon Fe 56. 
386. Name the elements constituting the Iron 
group. 
Clli;Qiaiura, manganese. iron. 
387. What arethe valences of these elements ? 
They are either bivalent or quadrivalent. 
They form two series- of compounds,In one of 
which the bivalent atom occurs, as in or 
FeO. In compounds oFTRe second series two 
atoms of the quadrivalent element combine, ex- 
changing a valence between them to- form a hexa- 
valent group, as in Fe^=Cl3 
I = (Fe2)Cl6. 
Fe=Cl3 
388. How are these two series distinguished by 
name ? 
That containing the less proportion of the more 
electro-negative element or radical is distin- 
guished by the termination ous ; that containing 
the greater proportion by the termination ic. 
Thus FeCl2 is ferrous chlorid, Fe2Cl8 feme 
chlorid. 102 
ESSENTIALS OP 
389. Give the formula of chromic anhydrid ? 
Cr03. It is also known, improperly, as chro- 
mic acid—Acidum chromicum, U. S. F. 
390. How is it prepared, and what are its uses ? 
It is prepared by slowly adding 3 parts of sul- 
furic acid to 2 parts of a saturated solution of 
potassium dichromate ; upon cooling, a mass of 
dark red needles of CrOa separate, and are freed 
from excess of HaS04 by draining upon a porous 
tile. It is one of the most active oxidizing agents 
we have, and, as such, is used in the laboratory, 
and medicinally as an escharotic. In dilute solu- 
tion it is used as a hardening agent in histologi- 
cal laboratories. 
391. Explain the chemical difference between 
potassium chromate and dichromate. 
The former has the formula K2Cr04, and the 
latter K2Cr207 ; they are therefore not salts of 
the same acid, as are carbonate and bicarbonate 
of potassium, Na3C03 and NaHC03, and the 
name bichromate tends to mislead. The chro- 
mate is a salt of chromic acid, and the dicliromate 
a salt of dichromic acid. From the constitution 
of these and other salts we may consider that chro- 
mic anhydrid is capable of forming three acids : 
CrOs + H20 = H2OO4 = Chromic acid. 
2CrOs + H20 = HaCraOr = Dichromic acid. 
3CrO„ + H20 = HaCr3Oio= Trichromic acid. 
None of these acids have been separated ; they 
are only known in their salts. 
392. State the properties of K2 Ora Oi. 
It forms prismatic crystals of a fine orange-red 
chkomium. Cr. 52.4. color ; odorless ; having a bitter, acrid taste ; 
soluble in water. Poisonous. When mixed with 
sulfuric acid it forms a powerful oxidizing agent. 
393. What is “ chrome yellow ” ? 
Lead chromate, PbCr04. 
CHEMISTRY AND TOXICOLOGY. 
103 
MANGANESE. Mn. 54. 
394. Give an account of the most important oxid 
of manganese. 
Manganese dioxid, Mn02, also known as black 
oxid or peroxid of manganese, is the chief ore of 
manganese, and is used in the arts in obtaining 
chlorin by the decomposition of hydrochloric 
acid : 
Mn02 + 4HC1 = MnCl2 + 2H20 4- Cl, 
ivianganesf 
HinviH 
Hydro- 
ehlnrii> urtid 
Manganous 
. chlorid. 
Water. Chlorin 
When heated to redness it gives up part of its 
oxygen, and has been used for obtaining that ele- 
ment. 
395. What chemical interest has the oxid 
Mn20i ? 
It is an anhydrid, whose corresponding acid, 
H2Mn208, has not been separated, but some of 
the salts of which, called permanganates, are of 
importance. 
396. Give the formula and properties of potas- 
sium permanganate. 
K2Mn208. It forms slender, prismatic crys- 
tals, of a purple color with a bronze-like reflec- 
tion ; inodorous, and having a sweetish, astrin- 
gent taste. Quite soluble in water, the solution 104 
ESSENTIALS OF 
having a deep purple color, and a pink color 
rhen extremely dilute. 
397. How does K2Mn2Oe act as a disinfectant ? 
It is a very active oxidizing agent, and its ac* 
tion as a disinfectant is due to the oxidation of 
the organic matter which it causes. It forms the 
basis of Condy’s and several other disinfecting 
fluids. 
iron. Fe. 56. 
398. IIow do cast iron, wrought iron, and steel 
differ from each other in composition ? 
Mainly in the different quantity of carbon con- 
tained. Wrought iron is made from cast iron by 
burning out carbon; steel is prepared from 
wrought iron by causing it again to combine 
with carbon. Wrought iron is used in obtaining 
pharmaceutical preparations^ 
' 399; What is Ferrum recTuctum, U. S. P.f 
A pure and finely divided iron obtained by re- 
ducing (see Q. 54) an oxid of iron by hydrogen : 
Ferric 
oxid. 
Fe303 + 3Ha — Fen + 3H30 
Hydrogen. 
Iron. 
Water, 
Reduced iron, or iron by hydrogen, as it is 
also called, should leave no residue when at- 
tracted by the magnet; such a residue is unre- 
duced oxid. 
400. Give the formula and synonyms of ferric 
oxid. 
Fe2Os. Sesquioxid of iron, peroxid of iron, 
red oxid of iron, colcothar, rouge, Venetian red. 
401. What is the composition of iron rust ? 
Chiefly a ferric hydrate, having the composi- CHEMISTRY AND TOXICOLOGY. 
105 
tion 2Fea03,3H20, with small quantities of the 
carbonate. 
402. What is Ferri oxidum hydratum, IT. S. P., 
and how is it prepared ? 
Ferric hydrate, Fea03,3H2O, prepared by add- 
ing ammonium hydroxid to solution of ferric 
sulfate (Liq. ferri tersulfatis, U. S. P.): 
Fea(S04)3 + 6NII4HO = Fe203,3Ha0 + 
Ferric 
sulfate. 
Ammonium 
hydroxid. 
Ferric 
hydrate. 
+ 3(NH4)aS04 
Ammonium 
sulfate. 
The precipitated hydrate is collected upon a 
calico Alter and washed. 
403. To what medical use is ferric hydrate put, 
and how does it act f 
As an antidote in arsenical poisoning. By pro- 
ducing the insoluble ferric arsenite. 
404. What decomposition occurs when this pro- 
duct is dried ? 
It loses two molecules of water, and is con- 
verted into the hydrate, Fe203,H20 = Ferri per- 
oxidum hydratum, Br. 
405. Give the formula, method of preparation, 
and use of ferrous sulfid. 
FeS. It is prepared by heating together sul- 
fur and iron Alings, and is used in the laboratory 
to obtain hydrogen sulAd. 
406. Give the formula and synonyms of ferric 
chlorid. 
FeaCl<>. Ferri chloridum, U. S., Br. Sesqui- 
chlorid of iron, perchlorid of iron. 106 
ESSENTIALS OF 
407. Give the TJ. S. P. method of its preparation. 
Iron is dissolved in hydrochloric acid, when 
ferrous chlorid, FeCl2, is formed! Tills is then 
boiled with nitric acid and excess of hydrochloric 
acid, by which FeCl2 is converted into Fe2Cl8. As 
thus prepared it always contains an excess of acid. 
408. How may neutral ferric chloridbe obtained ? 
By heating iron in a current of chlorin, Fe2Cl6 
condenses in the cool part of the tube. 
409. Give the formula and synonyms of ferrous 
sulfate. 
FeSOi. Ferri sulfas, U. S., Br. Sulfate of 
iron, green vitriol, copperas. 
410. State the method of its preparation and its 
properties. 
It is prepared by dissolving iron in dilute sul- 
furic acid and evaporating the solution to the 
point of crystallization. It forms apple-green 
crystals, containing 7Aq, odorless, having a 
sweetish, styptic taste, very soluble in water, in- 
soluble in alcohol. 
411. Give the analytical characters of the fer- 
rous salts. 
1. With potassium liydroxid, a greenish preci- 
pitate, insoluble in excess, and turning darker 
green and brown on exposure. 
2. With potassium ferrocyanid, a white preci- 
pitate, turning blue on exposure. 
3. With potassium ferricyanid, a dark blue 
precipitate. 
412. Give the analytical characters of the ferric 
salts. 
1. With potassium hydroxid, a voluminous, 
red-brown precipitate. CHEMISTRY AND TOXICOLOGY. 
107 
2. With H2S in acid solution, a milky precipi- 
tate of elementary sulfur. 
3. With potassium ferrocyanid, a dark blue 
precipitate, insoluble in HC1, soluble in KHO. 
4. With potassium (or ammonium) thiocyan- 
ate, a deep red color, discharged on addition of 
mercuric chlorid solution. 
413. 11 hat is produced on addition of ammonium 
sidfhydrate solution to a solution of a ferrous or 
ferric salt ? 
A black precipitate of ferric sultid, readily 
soluble in HC1. 
414. What are Prussian blue and Turnbull’s 
blue ? 
Prussian blue is ferric ferrocyanid, obtained 
by adding potassium ferrocyanid solution to a 
solution of a ferric salt (3, Q. 412). Turnbull’s 
blue is ferrous ferricyanid, obtained by preci- 
pitating a solution of a ferrous salt with potas- 
sium ferricyanid (3, Q. 411). 108 
ESSENTIALS Of 
GROUP III. THE ALUMINIUM GROUP. 
Glucinium . G1 9 
Aluminium A1 27 
Scandium Sc -45 
Gallium Ga 69 
Indium In.. 113 
415. What are the common characters of the 
elements of this group ? 
They form but a single series of compounds 
and salts, corresponding to the ic series of the 
preceding group, each of which contains^a 
double atom of the element, behaving as iThexa- 
valent group. No compounds corresponding to 
the qi/s series of the second group are known. 
In other respects the terms of this group resem- 
ble those of the preceding closely. 
ALUMINIUM. Al. 27.5. 
416. What is a notable physical property of alu- 
minium ? 
Its great lightness. Of all the metals it is 
the lightest, with the exception of the metals of 
the alkalies, which latter, however, cannot be 
kept unaltered in air. Aluminium is also quite 
tough, and is very useful in the manufacture 
of metal appliances where lightness is an ob- 
ject. CHEMISTRY AND TOXICOLOGY. 
109 
417. IIo'ic does aluminium exist in nature? 
Tt is one of the most abundant of the elements. 
Its oxid, A1203, exists nearly pure as corundum, 
ruby, and sapphire, and in a less piire form as 
emery. Its silicate, combined with other sili- 
cates/ forms the different varieties of clay, mica, 
feldspar etc. 
4 Vo. Explain the constitution of an alum. 
The sulfate of aluminium, in common with 
ferric, manganic, and chromic sulfates, possesses 
a great tendency to combine with the sulfates 
of potassium, sodium, and aipmonimn, to form 
definite double salts, which*are called alums. 
Thus we have : 
A13(S04)3,K2S04 = Aluminium potassium sul- 
fate. 
Cr2(S04)3,(NH4)2S04 = Chromic ammonium sul- 
fate. 
Fe2(S04)3,Na2S04 = Ferric sodium sulfate. 
We may therefore express the composition of an 
alum, in a general way, by the formula: 
in which R represents an atom of Cr, Mn, Fe, 
Gl, Al, Sc, Ga, or In ; and M an atom of Li. Na, 
K, Cs, Rb, or a group (NH4). 
419. To what substance is the name “ alum ” 
commonly applied? 
To the aluminium ammonium sulfate, crystal- 
lizeff'With 24 molecules ja£ water of crystalliza- 
tion : A12(S04)3,(NH4)2S04 + 24Aq. It is also 
known as “ammonia alum,” and isjjmalnmen, 
Br. The alumen, U. S., is the corresponding 
(R2)vi(S04)3,M'2S04 110 
ESSENTIALS OF 
potassium salt, formerly the “alum” of com- 
merce, but now almost universally replaced by 
the ammonium salt. 
420. Wherein does Alumen exsiccatum, U. S., 
Br., differ from alumen ? 
In having been subjected to heat, whereby the 
24 molecules of water of crystallization are driven 
off. It is known commercially as ‘ ‘ burnt alum. ” 
421. Give the tests for aluminium. 
1. With potash or soda, a white precipitate, 
soluble in excess of the precipitant. 
2. With ammonium hydroxid. a white precipi- 
tate, almost insoluble in excess. 
3. With disodic phosphate, a white precipi- 
tate, soluble in HC1, HN03, or H2804. 
4. A solid compound of aluminium, heated on 
charcoal by the blowpipe flame in presence of co- 
balt nitrate, assumes a dark sky-blue color. 
(For other elements of this group and the 
“ periodic law,” see Manual, pp. 162, 163.) CHEMISTRY AND TOXICOLOGY. 
GROUP V. 
422. Give the symbol, atomic weight, and va- 
lence of lead. 
Symbol = Pb (Latin, Plumbum). Atomic 
weight = 207. It_ig_MvalfiaLiaJBQat of 
pqiimls ; in some quadrivalpnt. 
423. What mineral is the most important ore of 
lead ? 
A native sulfid, PbS, called galena. It fre- 
quently contains a considerable quantity of sil- 
ver. 
424. Name some of the alloys into whose compo- 
sition lead enters. 
Type metal, pewter, britannia metal, solder, 
shot. The last-named contains arsenic. 
425. Describe the physical properties of lead. 
A bluish-gray metal; brilliant upon freshly 
cut surfaces ; vei’y soft and pliable ; not readily 
malleable or ductile ; a poor conductor of electri- 
city ; a better conductor of heat. Specific grav- 
ity = lffi. 
Describe the actions of HOI, of UNO.h and 
of IliSOi upon Pb. 
It is partly dissolved as PbCL by strong HCl, 
particularly if heated. It is readily dissolved by 
HN03 as lead nitrate. Strong HsS04 attacks Pb, 
solving a portion as lead sulfate, which is, 
Lead Pb 207 112 
ESSENTIALS OF 
however, precipitated as a white powder when 
II20 is added. Dilute II2S04 produces a white 
coating of lead sulfate upon the metal. (See Q. 
95.) 
427. What is the formula of lead monoxid, and 
under what other names is it known ? 
PbO. Plumbi oxidum, U. S., Br.; litharge; 
massicot. 
428. How is it prepared, and what are its prin- 
cipal properties ? 
It is prepared by heating lead in a current of 
air ; direct union of the lead and oxygen takes 
place, forming a yellow powder known as mas- 
sicot. When heated to redness this fuses, and, 
on cooling, forms coppery, crystalline scales, in 
which form it is known as litharge. Litharge 
should not be fused in an earthen crucible, as it 
combines with the silicic anhydrid to form a fu- 
sible lead silicate, and thus perforates the cruci- 
ble. Litharge is sparingly soluble in water ; the 
solution absorbs C02 from the air, and lead car- 
bonate is precipitated. It is also soluble in solu- 
tions of the hydroxids of potassium, sodium, and 
calcium. It is a powerful base. 
429. For what purposes is PbO used in the arts? 
In the manufacture of glass, white lead, red 
lead, acetate of lead, for communicating a drying 
power to oils, in making the various plasters 
used in pharmacy. A solution of PbO in lime 
water is used as a hair dye ; the lead, combining 
with sulfur from the hair, forms the black lead 
su lfid. 
430. Give the formula and other names of lead 
dioxid. CHEMISTRY AND TOXICOLOGY. 
113 
PbOa. Puce-colored oxid of lead ; peroxid of 
lead ; plumbic anhydrid. 
431. Why is the name ‘plumbic anhydrid given 
it? 
Because it is the anhydrid of a weak acid hav- 
ing the formula HaPbOa, AlthougfTthe acid has 
not been obtained, several of its salts are known, 
e.g., K2P03 = potassium plumbate. 
432. How is red lead obtained. and under what 
other name is it known? 
~ Litharge is further oxidized by roasting it in 
contact with air. It is known as red oxid of 
lead ; minium. 
433. What is the composition of red lead ? 
It has nof a constant composition, being a mix- 
ture, in various proportions, of two substances; 
one the lead salt of plumbic acid (see Q. 431), 
or lead plumbate, PbjPbO.. and tne other lead 
monoxid, PbO. It usually has the composition 
PbPb03 + PbO. 
434. What compound of lead with a, mineral 
acid is soluble in watery and how is it obtained ? 
The nitrate, Pb(N03)a. It is~Tbrmed by dis- 
solving the oxids or carbonate of lead in nitric 
acid : 
PbO + 2HN03 = Pb(N03)a + HaO 
Litharge. 
Nitric acid. 
Lead nitrate. 
Water. 
435. What are the uses of lead nitrate ? 
It is used in preparing the iodid. It enters into 
the composition of many disinfecting fluids. 
Ledoyen’s disinfectant is a solution of this sub- 
stance of the strength of a drachm to the fluid- 
ounce. 114 
ESSENTIALS OF 
436. Give the formula of lead iodid, and its 
method of formation. 
Pbl2. It is obtained by adding solution of 
potassium iodid to solution of lead nitrate : 
Lead 
nitrate. 
Pb(N03)a + 2KI = 2KNOs -t- Pbl2 
Potassium 
iodid. 
Potassium 
nitrate. 
Lead 
iodid. 
437. State the properties of lead iodid. 
It forms a lemon-yellow powder, very spar- 
ingly soluble in cold water, more soluble in hot 
water, from which latter solution it separates in 
crystals. Its solution is colorless. 
438. What yellow pigments are oxychlorids of 
lead? 
Cassel, Paris, Verona, and Turner’s yellows. 
439. What is chrome yelloic ? 
Neutral lead chromate. 
440. Give the chemical and pharmaceutical 
names and formula of sugar of lead. 
Neutral lead acetate; Plumbi acctas, U. S., 
Br.; Pb(C2H303)3 + 3Aq. It is sometimes called 
salt of Saturn. 
441. State the prominent properties of neutral 
lead acetate. 
It crystallizes in large, colorless prisms. It 
is sweetish in taste, with a metallic after-taste. 
With water and with alcohol it forms solutions 
which are acid in reaction. 
442. What reaction takes place betioeen lead ace- 
tate and zinc sulfate? 
The insoluble lead sulfate is precipitated and 
zinc acetate remains in the solution : 
Pb(CaH3Oa)a + ZnS04 = PbS04 + Zn(CaH3Oa)a. CHEMISTRY AND TOXICOLOGY. 
115 
443. Why are lead acetate and the vegetable 
astringents incompatible ? 
Because thetannic acid of the astringent com- 
bines with tlieTead to produce an insoTuhleTead 
Jannate. 
444. What pharmaceutical preparation contains 
a basic lead acetate, and how is it prepared ? 
Liquor plumbi subacetatis, U. S., Br.; also 
known as Goulard’s extract. 
It is prepared by boiling a solution of lead 
acetate with litharge. 
445. What is white lead ? 
A basic lead carbonate. 
446. What is meant by a basic or sub salt? 
A compound of the normal salt with a liydroxid, 
hydrate, or oxid of thS THEl&ir “Thus, the normal 
IckfTcarbonate being' I’bUth, the basic carbonate 
constituting the greater part of white lead is 
Pb(C0:i)s,PbH302. 
447. Give the analytical reactions of lead. 
1. With HoS in acid solution, a black precipi- 
tate, insoluble in alkaline sulfids. 
2. With ammonium sulfhydrate, a black pre- 
cipitate, insoluble in excess. 
3. With HC1, a white precipitate, if the solution 
be not too dilute. On heating, the precipitate is 
dissolved, and again deposited as a crystalline 
sediment on cooling. 
4. With ammonium liydroxid, a white precipi- 
tate. 
5. With II2S04, a white precipitate. 
6. With potassium iodid, a yellow.precipitate. 
7. With potassium chromate, a yellow precipi- 
tate. 116 
ESSENTIALS OF 
8. Iron and zinc separate tlie metal from solu- 
tions of its salts. 
448. Describe the prominent symptoms of acute 
lead poisoning. 
Metallic taste ; dryness of the throat; thirst ; 
severe colicky abdominal pains, referred parti- 
cularly to the umbilical region, and relieved by 
pressure; pulse very feeble and slow; great pros- 
tration; constipation; urine scanty and red; vio- 
lent cramps; paralysis of the lower extremities; 
convulsions; and tetanic spasms. 
449. 1Xhat is the best antidote in acute lead 
poisoning ? 
Magnesium sulfate, which brings about the 
formation of the insoluble lead sulfate, while the 
purgative action of the magnesia is also useful. 
It should be preceded by an emetic,’or by the use 
of Jthfi stomach pump. 
450. What is the prognosis in acute lead poison- 
ing ? 
Favorable; about 80 per cent, jgccufer. 
451. Give some of the prominent causes of chronic 
lead poisoning. 
The contamination of drinking water from lead 
pipes. Contamination of articles of food or drugs 
by contact with leaden vessels, or from being en- 
closed in tinfoil containing an excess of lead. 
Drinking beer, cider, etc., which has been drawn 
through leaden pipes or allowed to stand in 
pewter vessels. The ingestion or constant hand- 
ling of lead or its compounds, as the acetate, 
nitrate, carbonate (white lead—painter’s colic), 
Goulard’s extract, etc. The use of hair dyes 
containing lead. CHEMISTRY AND TOXICOLOGY. 
117 
GROUP VI. 
Bismuth Bi 207.5 
452. What are the symbol, atomic weight, and 
valence of Bi ? 
Symbol = Bi. Atomic weight = 207.5. It is 
trivalent. 
453. What are its physical properties ? 
A white, metallic substance, having peculiar 
reddish and greenish reflections ; very brittle; 
fuses at 268° (514° F.); expands considerably on 
cooling; crystallizes in cubes; forms alloys with 
metals, some of which are fusible at very low 
temperatures. 
454. IIow is bismuth purified for use in phar- 
macy, and what is the object of the purification ? 
Commercial bismuth is always contaminated 
witli arsenic, to separate which it is fused with 
about one fifth its weight of potassium nitrate. 
455. What is the action of nitric acid on bis- 
muth ? 
When bismuth is treated with nitric acid it is 
dissolved, brown fumes being given off. On cool- 
ing, white crystals of bismuth nitrate, Bi(N03)3, 
form. 
456. What is the action of water upon bismuth 
\nitrate ? 
When the above solution is diluted with water, 
a white precipitate is formed. This is bismutliyl 
nitrate, or a nitrate of the group (BiO), which be- 
haves as an atom of an univalent metal: 118 
ESSENTIALS OP 
Bismuth 
nitrate. 
Bi(N03)3 + H20 = BiO(N03) + 2HN03 
Water. 
Bismuthyl 
nitrate. 
Nitric 
acid. 
This new substance is what is known as sub- 
nitrate of bismuth ; Bismutlii subnitras, U. S., 
Br. The process by which the salt is prepared 
pharmaceutically is more complicated ; the ob- 
ject being the separation of arsenic. 
457. What are the so called oxysalts or subsalts 
of bismuth ? 
They are salts of the group (BiO)', bismuthyl, 
which always behaves as an atom of an univalent 
metal; thus we have : 
Bismuth. Bismuthyl. 
Chlorid BiCU (BiO)Cl. 
Bromid Bi Br3 (BiO)Br. 
Nitrate Bi(N03)3.. (BiO)NOs. 
Sulfate (Bi)2(S04)3 (Bi0)2S04. 
Carbonate (Bi)2(C03)3.. .(Bi0)2C03. 
458. Describe the tests for bismuth. 
1. With II20, a white precipitate, except in 
presence of free HC1, HN03, or H2S04. 
2. With II2S, a black precipitate, insoluble in 
alkaline sulfids. 
3. With potassium, sodium, or ammonium 
liydroxid, a white precipitate, turning yellow 
when the liquid is boiled. 
4. With potassium ferrocyanid, a yellowish 
precipitate. 
5. With potassium ferricyanid, a yellowish 
precipitate. 
6. With potassium iodid, a brown precipitate, 
soluble in excess. chemistry and toxicology. 
119 
GROUP VII. THE TIN GROUP. 
Titanium Ti 50. 
Zirconium Zr 90. 
Tin Sn 117.7 
TIN. 
459. What are the symbol, atomic weight, and 
valence of tin ? 
Its symbol is Sn (Latin, Stannum). Its atomic 
weight is 118. It forms two series of compounds, 
in one of which it is bivalent, and in the other 
quadrivalent. 
460. For what purposes is tin used in the arts ? 
1. For protecting iron from the action of air 
and moisture ; the various “ tin” articles used in 
the household are made of iron covered with a 
thin layer of tin. 2. For manufacturing tinfoil. 
3. In the silvering of looking-glasses. 
461. What are meant by stannous and stannic 
compounds ? 
Those compounds of tin in which that element 
is bivalent are called stannous : SnCL = stannous 
chlorid ; those in which it is quadrivalent are 
called stannic : SnCL = stannic chlorid. 
462. JTow is stannous chlorid obtained, and 
what are its uses ? 
By dissolving tin in hydrochloric acid with the 
aid of gentle heat. It is a strong reducing agent, 120 
ESSENTIALS OF 
and is used in calico printing, and in the labora- 
tory as a reagent for gold and mercury. 
463. Give the analytical characters of the stan- 
nous compounds. 
1. With ammonium hydroxid, a white preci- 
pitate, turning olive brown when the liquid is 
boiled. 
2. With II2S, a dark-brown precipitate, solu- 
ble in alkaline sullids, in potassium hydroxid, 
and in hot H20. 
3. With mercuric chlorid, a white precipitate, 
turning gray and black. CHEMISTRY AND TOXICOLOGY. 
121 
GROUP VIII. THE PLATINUM GROUP. 
Palladium Pd .. 105.7 
Platinum Pt 194.4 
PLATINUM. 
464. 1Tow does platinum behave toward the 
mineral acids ? 
It is indifferent toward any single mineral acid. 
Aqua regia dissolves it readily, with formation of 
platinic chlorid, PtCl4. 
465. To what uses is metallic platinum put ? 
In making crucibles, dishes, and other vessels 
destined to bear a high heat without fusion, and 
in which acids may be heated. Large retorts 
made of this metal are used in the concentration 
of sulfuric acid. 
466. What precautions are to be had in using 
platinum vessels ? 
Although not attacked by single acids, plati- 
num vessels are injured by many substances. 
The metal is attacked by nitromuriatic acid, or 
any substance liberating chlorin. Platinum has 
a great tendency to alloy with other metals ; 
therefore no metal or easily reducible oxid 
should be heated in contact with it. The alka- 
lies and alkaline carbonates and, under certain 
conditions, the alkaline phosphates attack plati- 122 
ESSENTIALS Of 
num. When these substances are to be heated, 
silver vessels should be used, care being taken, 
however, that the heat be not pushed beyond 
the fusing point of that metal. Platinum vessels 
should never be heated over an alcohol or coal 
fire, because when so heated the metal becomes 
blackened and brittle. 
467. What is the valence of platinum ? 
It forms two series of compounds, in one of 
which it is bivalent, as in Pt"Cla = platinous 
chlorid ; and in the other quadrivalent, as in 
PtivCl4 = platinic chlorid. 
468. For what purpose is platinic chlorid used 
in chemistry ? 
As a test for the presence of the compounds of 
potassium and ammonium, with which it forms 
insoluble, yellow, crystalline compounds ; and as 
a test for certain alkaloids. chemistry and TOXICOLOGY. 
123 
CLASS IV. BASYLOUS ELEMENTS. 
469. What are the characteristics of the basylous 
elements ? 
Their oxids combine with water to form bases, 
never to form acids. They are capable of dis- 
placing the hydrogen of the oxyacids to form 
oxysalts. 
470. What elements are designated as metals ? 
Those which are capable of displacing the hy- 
drogen of oxyacids to form oxysalts. The am- 
photeric and basylous elements. 
471. Name the principal basylous elements. 
Lithium, sodium, potassium, silver, calcium, 
barium, magnesium, zinc, copper, mercury. 
GROUP 1. THE ALKALINE METALS. 
Lithium Li 7 
Sodium Na... 23 
Potassium Iv 39 
Rubidium Rb 85.3 
Caesium Cs 133. 
Silver Ag 108 
Note.—Silver is not usually included in this proup. It 
differs from the other members entirely in its physical 
properties and in being: much less alkaline ; but it resem- 
bles them in its valence and in the nature of its com- 
pounds. 124 
ESSENTIALS OF 
472. What term is used to designate the elements 
of this group t 
The alkaline metals. 
473. What are the common characters of the 
members of this group ? 
Each forms a single chlorid and one or more 
oxids. Their hydroxids, M'HO, are strongly 
basic. They are univalent. 
474. To what elements was the name metalloid 
first applied, and why? 
To potassium and sodium. The word metal- 
loid signifies “like a metal,” and was given to 
these elements at the time of their discovery, be- 
cause, although resembling the then known 
metals in some physical characters, they differ 
from them in others. 
475. What are the symbol and atomic weight of 
lithium f 
Its symbol is Li ; its atomic weight 7. 
476. What compounds of lithium are used in 
medicine ? 
The bromid, LiBr = Lithii bromidum, U. S. ; 
and the carbonate, Li2C03 = Lithii carbonas, 
U. 8., Br. 
LITHIUM. 
SODIUM. 
477. . What are the symbol and atomic weight of 
sodium ? 
Its symbol is Na (Latin, Natrium). Its atomic 
weight is 23. CHEMISTRY AND TOXICOLOGY. 
125 
478. What are the physical properties of ele- 
mentary sodium f 
When pure, it is a brilliant, silver-white.nietal, 
crystallizing in cubes. As commonly met with, 
it is a bluMi metal, coated with a brown film. 
It is lighter than water (sp. gr. 0.972). It fuses 
at 95°.6 (204°. 1 F.), and maybe distilled in an 
atmosphere of hydrogen. It is waxy in con- 
sistence at the"ormnary temperature. 
’ 479’. What is the action of sodium on water ? 
If a fragment of sodium be thrown upon wa- 
ter, it floats upon the surface, and gradually dis- 
appears, with a hissing noise, while hydrogen is 
given off and caustic soda is formed : 
Na2 + 2EI.iO = 2NaH0 + II, 
Sodium. 
Water. 
Sodium 
hydroxid. 
Hydrogen. 
Sodium is similarly converted into NaHO by 
exposure to damp air ; hence it should be kept 
in some liquid free from oxygen, as benzine, or 
in closely sealed vessels. 
480. How is metallic sodium prepared ? 
By heating a mixture of dry sodium carbonate, 
chafk, and charcoal to a white,heat. 
481. What are the chemical name and formula 
of caustic soda ? 
Sodium hydroxid—NaHO. 
482. Describe the prominent properties of NaHO. 
It is a hard, white, amorphous solid, very solu- 
bletrr Water, forming solutions which are intense- 
ly alkaline in reaction. ' ' 
It is a powerful base, neutralizing acids with 
formation of sodium salts, and a strong corrosive. 126 
ESSENTIALS OF 
On exposure to air it absorbs carbon dioxid and 
is converted into the carbonate. A strong solu- 
tion of NaHO is called “ Soda lye.” 
483. What is common salt ? 
Sodium chlorid, NaCl. 
484. Where does NaCl occur in nature? 
In the mineral world, deposited in the solid 
form, as “rock salt” ; in soils; and in solution, 
in varying quantities, in all natural waters. In 
all animal tissues and fluids, and in less quantity 
in vegetable tissues. 
485. What are the chief uses of NaCl in the 
arts ? 
As a starting-point in the manufacture of most 
of the sodium compounds, hydrochloric acul, 
chlorin, bleaching powder ; in the preservation 
of meats, fish, etc., and in glazing potfeTy. 
486. What are the chief impurities of com- 
mercial salt ? 
Chlorids of calcium and magnesium. They 
communicate to the salt a somewhat bitter taste, 
and the property of absorbing moisture from the 
air.1 
~~487. What functions does NaCl perform in the 
animal economy? 
It aids in the phenomena of osmosis throughout 
the body ; aids in holding certain of the albu- 
minoids in solution ; and is the source from which 
the hydrbcTiloric acid of the gastric juice is prob- 
ably derived,, 
'T887 TTowis it eliminated ? 
By all the excretions, principally in the urine. 
(See Manual, p. 178.) CHEMISTRY AND TOXICOLOGY. 
127 
489. What data are required to calculate the 
quantity of bromin in 100 parts of sodium bro- 
mid ? 
1st. Its formula—NaBr. 2d. The atomic 
wTeight of sodium—28, and that of bromin—80 ; 
the sum being of course the molecular weight of 
NaBr = 103. 3d. Whether or no the substance 
in the condition used contains water of crystalli- 
zation or not. • 
Note.- This last point must not be lost sight of. NaBr 
contains no water of crystallization, and if we weigh out 
103 parts we will have 80 parts Br ; but suppose it con- 
tained 1 molecule of water of crystallization, its formula 
would then be NaBr -(- Aq, and to get 80 parts Br we 
would have to take 23 + 80 + 2 + 16 = 121 parts. 
490. Calculate how much iodin there is in 100 
parts of sodium iodid. 
Its formula is Nal, and it contains no water of 
crystallization. Its molecular weight is, there- 
fore, 23 + 127 = 150, or 150 parts Nal contain 
127 parts I. Therefore : 
150 :100 :: 127 : x x = 84.66 
491. Give the formula and synonyms of sodium 
nitrate. 
NaN03. Chili saltpetre ; cubic nitre ; Sodse 
nitras, tJ. S., Br. 
492. Give the formula1, and names of the mlfates 
of sodium. 
Monosodic sulfate. NaHS04, also known as 
acid sodium sulfate or bisulfate of sodium. Di- 
sodic sulfate, Na2S04, ' also known as neutral 
sodium sulfate, Glauber’s salt; Sodii sulphas, 
U. S. f Sodae sulphafC!^' 128 
ESSENTIALS OP 
493. Where does disodic sulfate occur in the ani- 
mal economy ? 
Ia all tissues aud fluids, except the milk, bile, 
and gastric juice. 
494. Give the formula} and names of the phos- 
phates of sodium. 
Mouosodic phosphate, Nalljl’O, = acid so- 
dium phosphate. Disodic phosphate. NaaHPO« 
= phhfcpkate of soda; Sodii phosphas, U. S.; 
Sod* phosphas, Br. Trisodic phosphate, Na;i- 
P04 = basic phosphate of soda. 
The first named crystallizes with lAq, the last 
two with 12Aq. 
495. In what portions of the animal body do the 
phosphates of sodium occur ? 
In all parts. 
.496. In what animal fluids does the trisodic 
phosphate predominate, and what function does it 
perform? 
In the blood; in greater proportion the more 
strictly animal the diet. The alkalinity of the 
blood is largely fliicTo this salt. 
“497. Th 'dTull relative proportions do the phos- 
phates of sodium and potassium occur in the 
body ? ' 
They accompany each other in all parts; the 
sodium salt being much more abundant in all 
situations except in the bldOU corpuscles and 
in the muscular tissue, in which the potassium 
compounds predominate. 
498. To w/eat is tine acid reaction of human urine 
due? 
To the presence of monosodic and nionopotas- 
sic phosphates. CHEMISTRY AND TOXICOLOGY. 
129 
499. How are phosphates produced in the animal 
body ? 
By the processes of disassimilation of nerve- 
tissue, which contains phosphorized organic sub- 
stances, the oxidation of whose phosphorus is 
attended by the formation of phosphates. 
500. What are the alkaline phosphates of the 
urine ? 
The phosphates of sodium and potassium. 
They are so called because they are the phos- 
phates of the “alkaline metals,” although they 
are acid salts. (See Laboratory Guide, pp. 53- 
55.) 
501. What is borax f 
Sodium pyroborate, or tetraborate, Na2B407 + 
lOAq. 
502. What sodium salt exists in Liq. 8oda>, Chlo- 
rinates, U. 8., Br. ? 
Sodium hypochlorite, NaClO. 
508. Give the names and formula of the carbo- 
nates of sodium. 
Monosodic carbonate. NalICQ,. also called 
bicarbonate of soda, cooking soda, acid carbonate 
dfsbda, Sodii bicarbonas, U. S., and Sodas bicar- 
Bonas, Br. Disodic carbonate, called 
carbonate of soda, washing soda., sal-soda, soda, 
soda crystals, Sodii carbonas, U. S., and Sodse 
carbonas, Br. 
The former crystallizes without Aq. the latter 
with lOAq. 
504. What is the reaction of solutions of these 
carbonates ? 
It is distinctly alkaline; that of the carbonate 130 
ESSENTIALS OF 
being more markedly so than that of the bicar- 
bonate. 
505. Of what importance is the disodic carbonate 
in the arts ? 
It is manufactured in large quantities, and is 
used in many important industrial operations, 
e.g., glass and soap manufacture, calico print- 
ing, irfft as a starting-point in obtaining the 
various compounds of sodium. It is used in the 
laundry to soften hard water. 
”506. How are the carbonates of potassium and 
sodium formed in the economy, and what is their 
function ? 
By the oxidation of sodium and potassium 
salts of other organic acids existing in plants. 
Their main function is the preservation of alkaline 
reaction of the circulating fluids in the lierbivora, 
and to a greater or less degree in man. The ad- 
ministration of vegetable acids communicates an 
alkaline reaction to the urine by reason of their 
oxidation in the body, with formation of carbo- 
nates of sodium and potassium. 
507. To what substance does the name sal aera- 
tus properly apply, and to what is it commonly 
applied ? 
It was originally used to designate potassium 
bicarbonate, but at present the article universally 
sold and used under the name “ sal aeratus ” is 
pionosodic carbonate. 
508. For what purpose and how is monosodic 
carbonate used in baking ? 
As a source of carbon dioxid gas, whose libera- 
tion “raises” the bread. It is used either along 
or combined with some acid salt. CHEMISTRY AND TOXICOLOGY. 
131 
509. Why should it not be used alone ? 
Because under the influence of heat it is de- 
composed according to the equation: 
2NaHC03 = Na2CO + HaO + C02, 
and the product of the baking consequently con- 
tains the strongly alkaline disodic carbonate. 
510. What chemicals are used in the manufac- 
ture of baking powders ? 
Monosodic carbonate (bicarbonate); monopo- 
tassic tartrate (cream of tartar); alum (ammoni- 
um aluminium sulfate); monosodic phosphate ; 
tartaric acid; ammonium carbonate; starch. 
(See Manual, pp. 188, 189.) 
511. What are the symbol and atomic weight of 
potassium ? 
Its symbol is_K (Latin, Kalium) ; its atomic 
weight is 39. 
512. WKat are the physical properties of potas- 
sium ? 
A silver-white, metallic body ; soft at ordinary 
temperatures, melts at C'PTS (144°.5 F.), and at 
red heat boils, witli formation of green vapors. 
It is lighter t Man water. 
TET What is the action of potassium on water 
and air ? 
Potassium decomposes water with great en- 
ergy : 
POTASSIUM. 
K2 + 2IIaO = 2KHO + II a 
Potassium. 
W 
ater. 
Potassium 
hydroxid. 
Hydrogen. 132 
ESSENTIALS OF 
The action is so violent that flame and a slight 
explosion are produced. K has also a great 
tendency to unite with oxygen, and, if this be 
perfectly dry, potassium oxid, K20, is formed. 
When potassium is exposed to air, its surface is 
rapidly coated with a yellowish-white layer of 
KHO. In order to preserve the metal it must 
be kept under some substance containing no oxy- 
gen, as benzine. 
514. What is the constitution of potassium hy- 
droxid ? 
It is a molecule of water in which one atom of 
hydrogen has been replaced by one atom of po- 
tassium : 
pIP ) // , K ) 1_ oH ) q . II ) 
"IP f + K ~ "H fU + II C 
2 molecules 
water. 
1 molecule 
potassium. 
2 molecules 
potassium 
hyflroxid. 
1 molecule 
hydrogen. 
Or, in other words, it is a molecule composed of 
one atom of bivalent oxygen, united with one of 
each of the univalent atoms, hydrogen and po- 
tassium. 
515. Under what other names is potassium hy- 
droxid known f 
Potash ; Potassa, U. S.; Potassa caustica, Br.; 
Potassa fusa ; Potassa alba. 
516. What are the physical properties of KUO ? 
It is a hard, white solid (usually in the shape of 
sticks, about one-quarter inch in diameter and 
six inches long), opaque, brittle ; melts at a dull 
red heat; very soluble in water, less so in alcohol. 
Has a strong, soapy taste, even iu dilute solution. CHEMISTRY AND TOXICOLOGY. 
133 
517. Why should KIIO and its solutions be pro- 
tected from air? 
Because they rapidly absorb carbonic anhy- 
drid, forming potassium carbonate, and in course 
of time the hydroxid will be entirely replaced by 
the carbonate. 
518. State some of the chemical properties of 
KIIO. 
It is a powerful base, entering readily into re- 
action with acids to form salts : 
iao ♦ g*}o -gio + rfo 
Potassium 
hydroxid. 
Nitric 
acid. 
Water. 
Potassium 
nitrate. 
It has a strong alkaline reaction, and is a power- 
ful caustic, dissolving most animal tissues. In 
concentrated solution it attacks glass. Its solu- 
tion dissolves sulfur, phosphorus, chlorin, bro- 
min, and iodin, forming with these elements 
compounds soluble in water. 
519. What is the action of KIIO on ammo- 
nium salts ? 
Being a stronger base than ammonium, it de- 
composes the ammoniacal salt, with formation of 
a potassium salt, water, and ammonia : 
(NfK)NOa + KIIO = KNQ3 + NII3 + 
Ammonium 
nitrate. 
Potassium 
hydroxid. 
Potassium 
nitrate. 
Ammonia. 
+ HsO 
Water. 
520. What is the action of solution of KIIO on 
solutions of most metallic salts ? 
It decomposes the salt, with formation of the 134 
ESSENTIALS OF 
corresponding potassium salt and a metallic hy- 
droxid : 
Cupric 
sulfate. 
CuS04 + 2KHO = K,S04 + CuH,0, 
Potassium 
hydroxid. 
Potassium 
sulfate. 
Cupric 
hydroxid. 
Some of the hydroxids being of characteristic 
color, and insoluble in water, solution KHO is 
used as a test reagent. 
521. What is the composition of potassium chlo- 
rid, and where does it exist in nature ? 
KOI. It is very widely distributed in mine- 
ral, vegetable, and animal nature. As a double 
chlorid of potassium and magnesium it consti- 
tutes a mineral, called carnallite, which is the 
chief mineral source of the potassium com- 
pounds. It is found in all animal tissues and flu- 
ids, accompanying the corresponding sodium 
compound, but in much less quantity. In the 
red blood corpuscles and in muscular tissue the 
K salt predominates over the Na. 
522. What are the composition and physical 
p't'operties of potassium bromid f 
KBr. It forms milk-white cubes containing 
no water of crystallization ; unaltered by expo- 
sure to air ; odorless; having a peculiar salty 
taste. Soluble in H parts of cold water, and 
easily soluble in alcohol. 
523. What is the action of chlorin upon KBr? 
Write equation. 
It decomposes it, with formation of the chlorid 
and liberation of bromin : 
Chlorin. 
Cl, + 2KBr = 2KC1 + Br, 
Potassium 
bromid. 
Potassium 
chlorid. 
Bromin. CHEMISTRY AND TOXICOLOGY. 
135 
524. What reaction takes place between solutions 
of KBr and those of mercurous, lead, or silver salts ? 
The bromin unites with the mercury, lead, or 
silver to form corresponding bromids, which are 
insoluble. With solution of mercuric clilorid 
(corrosive sublimate) it gives no precipitate. If 
it do, the bromid is contaminated with potassium 
iodid. 
525. What are the composition and physical 
properties of potassium iodid ? 
KI. It forms milk-white cubes without water 
of crystallization ; odorless ; having a sharp, bit- 
terish, saline taste ; unaltered by exposure to air 
(when it becomes damp it is impure). Very solu- 
ble in water, less so in alcohol; the solutions be- 
ing clear, colorless, and neutral. 
526. Why is KI incompatible with the insoluble 
mercurials ? 
Because it renders them soluble to a greater or 
less extent, and consequently much more active. 
527. What takes place token KI and metallic 
salts are combined? 
The formation of the potassium salt of the acid 
and iodid of the other metal: 
Pb(C2H3Oa)a + 2KI = 2KCaH302 + Pbla 
Lead acetate. 
Potassium 
iodid. 
Potassium 
acetate. 
Lead 
iodid. 
This reaction is important in the cases of' lead, 
bismuth, copper, and silver. 
528. What is the action of chlorin, bromin, or 
fuming nitric acid upon KI? 
The salt is decomposed, with liberation of free 
iodin. 136 
ESSENTIALS OF 
529. What are the formula and common names 
of potassium nitrate? 
KN03. Potassii nitras, U. S. ; Potass* nitras, 
Br. ; saltpetre ; nitre. 
530. What is the origin of KN03 ? 
It has its origin in the oxidation of animal or 
vegetable substances rich in nitrogen, in the pre- 
sence of potassium. It is thus formed both na- 
turally and artificially. 
531. What are the chief uses of KNOs ? 
In the manufacture of nitric and sulfuric acids, 
and of gunpowder ; in packing beef and pork. 
In the laboratory it is used as an oxidizing agent. 
532. What are the formula and physical proper- 
ties of potassium chlorate? 
KC103 Occurs in transparent, colorless plates, 
without water of crystallization ; permanent in 
air ; odorless ; has a cool, salty taste ; soluble in 
30 parts of cold water ; sparingly soluble in alco- 
hol. Its aqueous solution is colorless, and neutral 
in reaction. 
533. What decomposition does KC103 undergo 
when heated? 
It first fuses, and at higher temperatures is de- 
composed, yielding oxygen and potassium chlorid: 
Potassium 
chlorate. 
2KC10S = 2KC1 + 302 
Potassium 
chlorid. 
Oxygen. 
This is the reaction generally utilized for the pro- 
duction of oxygen. 
534. What precaution is to be had in dispensing 
KClOs ? 
It should never be combined with any organic 
or easily oxidizable substance, or with any strong CHEMISTRY AND TOXICOLOGY. 
137 
acid or acid sulfate. With these substances 
KClOs is readily decomposed, forming substances 
which are violently explosive. 
535. What is Javelle Water ? 
A solution of potassium hypochlorite, KCIO; 
a compound which is only known in solution, 
and is formed by passing chlorin through a cold 
solution of potassium carbonate. It is a clear, 
colorless liquid, having an odor of chlorin, and 
a bleaching action upon vegetable colors. It is 
used in removing stains from fabrics. 
536. Give the names and formulae of the sulfates 
of potassi um. 
Monopotassic sulfate, KHS04, hydropotassic 
sulfate, acid sulfate, bisulfate of potassium. Di- 
potassic sulfate, K2S04, sulfate of potassium, 
Potassii sulphas, U. 8. ; Potass* sulphas, Br. 
537. Give the names and formula of the car- 
bonates of potassium. 
Monopotassic carbonate, KHC03 = hydropo- 
tassic carbonate, bicarbonate, Potassii bicarbonas, 
U. S. ; Potass* bicarbonas, Br. ; sal aeratus. 
Dipotassic carbonate, K3C03 = salt of tartar, 
pearl-ash, potash, Potassii carbonas, U. S. ; 
Potass* carbonas, Br. 
537a. Describe the analytical characters of lithi- 
um, sodium, and potassium. 
They are most readily detected by the colors 
which they communicate to the blue Bunsen 
flame : lithium, a bright red ; sodium, yellow ; 
potassium, violet. The latter is only visible in 
the presence of Na when the flame is observed 
through a blue glass, or a glass vessel filled with 
dilute indigo solution. 138 
ESSENTIALS OF 
Sodium salts form a white, crystalline precipi- 
tate with potassium pyroantimonate solution. 
Potassium chlorid gives a yellow, crystalline 
precipitate with platinic chlorid solution. The 
liquid must not contain ammoniacal salts. 
538. What action have the hydroxide of sodium 
and potassium upon the economy ? 
They act as powerful corrosives. The symp- 
toms are practically the same as those observed 
in corrosion by the mineral acids (see Q. 147), ex- 
cept in corrosion by the alkalies a soapy taste, 
followed almost immediately by a burning sensa- 
tion, is experienced in place of an acid taste. 
The reaction of the vomited matters, or of the 
vessel from which the corrosive was taken, is the 
most certain means of diagnosis. The method of 
death and post-mortem appearances, apart from 
reaction, are the same as in corrosion by the 
mineral acids. (See Q. 148, 151.) 
539. What is the action of the carbonates of so- 
dium and potassium on the animal economy f 
The same as that of the liydroxids, but much 
less intense in equal dose. In the case of the po- 
tassium salt, the true poisonous action (see Q. 
541) is usually the more important. 
540. What treatment should be adopted in cor- 
rosion by potash or soda ? 
The alkali should be neutralized as speedily as 
possible by the administration of a weak acid, 
acetic acid in the form of vinegar being the most 
available. Oils or milk are of service, more as 
emollients than as true antidotes. The stomach 
pump is not to be used. CHEMISTRY AND TOXICOLOGY. 
139 
541. How do the salts of potassium differ from 
those of sodium in their action on the animal 
economy? 
In any reasonable quantity the sodium com- 
pounds are inert beyond such action as they may 
owe to the acid or to their reaction. The potas- 
sium salts are possessed of truly poisonous quali- 
ties ; they cause dyspnoea, diminution of the 
blood pressure, convulsions, and death from 
arrest of the heart’s action. 
542. Give tlie syvibol and atomic weight of silver. 
Its symbol is Ag (Latin, Argentum); its atomic 
weight 108. 
548. State the principal physical properties of Ag. 
A white metal, capable of a high polish ; very 
malleable and ductile ; the best known conductor 
of heat and electricity ; harder than Au, softer 
than Cu; sp. gr. 10.4-10.5. 
544. Mention some of the chemical properties*of 
silver. 
It is not oxidized in dry pr moist air at any 
temperature. If the air contain traces“of hydro- 
gen sulfid the surface of the metal becomes tar- 
nished by the formation of the black silver sulfid. 
It is attacked at ordinary temperatures by Cl, By, 
I, and S. It is not attacked even at higlT tem- 
peratures by the caustic or carbonated alkalies. 
Silver acts readily upon nitric acid, vCftirTOTnia- 
tionoUUjpmtrate. 
T)40. What is coin silver ? 
An alloy of silver and copper. 
SILVEK. 140 
ESSENTIALS OF 
546. What is lunar caustic ? 
Silver nitrate, AgN03 = Argenti nitras fusa, 
U. S.; Lapis infernalis. It is prepared by dis- 
solving silver in nitric acid, and heating the crys- 
talline residue until it fuses, when it is cast into 
moulds. 
547. What action has nitrate of silver upon 
animal tissues ? 
In contact with animal matter silver nitrate is 
rapidly decomposed, metallic silver being depos- 
ited and producing the characteristic black stain, 
while free nitric acid is liberated. It is to the 
liberation of this substance that lunar caustic 
owes its action as an escharotic. — ■— 
548. (Jive the analytical 'characters of the silver 
salts. 
1. With HC1 a white precipitate, insoluble in 
HNOa, soluble in ammonium liydroxid. 
2. With NallO, or KHO, a brown precipitate, 
insoluble in excess. 
With H2S a black precipitate, insoluble in 
alkaline sulfids. 
AMMONIUM. 
549. What is the ammonium theory? 
The ammoniacal compounds, such as sal-am- 
moniac, are not compounds of ammonia gas, but 
of a group of atoms (NH4) called ammonium. 
This group behaves like an atom of an univalent 
metal, such as potassium. As potassium clilorid 
has the formula KC1, so ammonium chlorid lias 
the formula (NH4)C1. Liquor ammonite is not a 
simple solution of ammonia gas in water; it con- CHEMISTRY AND TOXICOLOGY. 
141 
tains a true ammonium hydroxid (NH4)HO, cor- 
responding in all respects to the hydroxids of 
potassium and sodium, KIIO and NallO, except 
that upon being heated it is decomposed into 
ammonia gas and water: 
(NH4)HO = nh3 + II20 
Ammonium 
hydroxid. 
Ammonia. 
Water. 
Ammonium has not yet been obtained in a free 
state with certainty, but an amalgam may be 
readily obtained, corresponding to the amalgams 
of sodium and potassium. (See Manual, p. 194.) 
550. What is the present source of the ammoni- 
acal compounds ? 
The “ammoniacal liquor v obtained in manu- 
facturing illuminating gas. This is distilled, and 
the distillate passed into HC1 or H2S04, when 
ammonium chlorid or sulfate is formed. 
551. IIow is ammonium sulfhydrate prepared ? 
By passing II2S through a solution of NH4HO: 
H | S + {N^4) [ O = (N”4) J S + {[ | O 
Hydrogen 
sulfid. 
Ammonium 
hydroxid. 
Ammonium 
sulfhydrate. 
Water. 
552. What are the properties and uses of the 
solution thus obtained ? 
When freshly prepared, it is a colorless liquid, 
having the odor of ammonia, as well as that of 
hydrogen sulfid; when old it assumes a yellow 
color. It is a valuable reagent in analysis, 142 
ESSENTIALS OF 
553. Give the names and formula of ammonium 
chlorid. 
Ammonium chlorid, muriate of ammonia, sal- 
ammoniac, Ammonii chloridum, U. S., Br. 
(NH4)C1. 
554. What reaction takes place when ammonia 
gas comes in contact with an acid? 
The two unite to produce an ammonium salt, 
without liberation of hydrogen, thus : 
Ammonia. 
NH3 4- IIC1 = (NII«)C1 
Hydrochloric 
acid. 
Ammonium 
chlorid. 
2NH3 + HaS04 = (NH4)aS04 
555. How are the ammoniacal compounds af- 
fected by heat ? 
They are completely volatilized, unless they 
are salts of a fixed acid. 
556. Give the analytical characters of the ammo- 
nium salts. 
1. When heated with KHO they give off Nlh, 
which may be recognized by its odor, by its 
turning moist red litmus paper blue, and by the 
formation of a white cloud when a glass rod, 
moistened with HC1 solution, is held over the 
vessel. 
2. With platinic chlorid, a yellow, crystalline 
precipitate, converted into a gray, spongy mass 
when heated. 
557. Wherein docs ammonium hydroxid differ 
from the hydroxide of potassium and sodium in its 
action on the economy ? 
Jn the severe dyspnoea which it produces, 
Ammonia. 
Sulfuric 
acid. 
Ammonium 
sulfate. CHEMISTRY AND TOXICOLOGY. 
Owing to the readiness with which NH3 is given 
off, the corrosive action of NH4HO is usually in- 
significant compared to the action of the NII3 
upon the air passages. 144 
ESSENTIALS OF 
GROUP III. METALS OF THE ALKALINE 
EARTHS. 
Calciom Ca 40 
Strontium Sr 87.5 
Barium Ba 137 
558. State the characteristics of elements of this 
group. 
They are bivalent; they form two oxids, hav- 
ing the composition MO and MO?; their sulfates 
and carbonates are insoluble or very sparingly 
soluble'; Their liydroxids are known as the aika- 
line earths. 
CALCIUM. 
559. How does calcium exist in nature? 
In its compounds it is one of the most abun- 
dant of the elements. Its carbonate exists as 
chalk, marble, limestone, etc.; its sulfate as gyp- 
sum and alabaster, and several other compounds 
exist in various minerals. Its compounds also 
occur in animal and vegetablej,issues. 
560. 'Hive the formula and common names of 
calcium monoxid. 
CaO. Calx, U. S., Br.; Calx viva ; quicklime. 
561. State the method of its preparation, and its 
properties. 
It is obtained by heating limestone, which is a CHEMISTRY AND TOXICOLOGY. 
145 
native calcium carbonate. It forms white, amor- 
phous masses. It is od.orless; has a caustic, al- 
kaline taste, and' alkaline reaction. When ex-' 
posed to the ft water and carbonic 
anhydrid, falling to a powder composed of a 
mixture of calcium carbonate and hydroxid ; it 
is then said to he jpr-slaked. 
562. What takes place when calcium monoxid is 
treated with water ? 
When H20 is thrown upon CaO, a crackling 
sound is heard, much heat is liberated, the lime 
swells up, and calcium hydroxid is formed : 
CaO + H20 = CaH202 
Calcium 
monoxid. 
Water. 
Calcium 
hydroxid. 
This is known as slaked lime, and is a light, 
white powder, odorless, having an alkaline taste 
and reaction, it is sparingly soluble in cold 
HaO, and less soluble in hot HaO. It absorbs 
carbonic anhydrid read ilyTroffT the air, forming 
calcium carbonate. 
5615. IV hat are lime water and milk of lime ? 
The former is a solution of calcium hydroxid 
in water ; the latter is such a solution Eolding in 
suspension a great excess of calcium hydroxid 
564. Give the formula andTcommon names of 
calcium chlorid. 
CaCla. Calcii chloridum, U. S., Br.; muriate 
of lime. 
565. How is it obtained, and what are its promi- 
nent properties ? 
It is formed when hydrochloric acid acts upon 
a compound of calcium which it is capable of 
7[gcQm.nnaia sr ; 146 
ESSENTIALS OP 
Marble. 
CaCO, 4- 2HC1 = CaCl2 + H20 + C02 
Hydrochloric 
acid. 
Calcium 
chlorid. 
Water. 
Carbonic 
anhydrid 
It is odorless, and has a sharp, salty taste. When 
fused and allowed to cool, it forms a rough, 
amorphous mass, which absorbs water with 
great energy and is used as a^dmngyjgsfli. 
565. What is the difference oetween calcium 
chlorid and chloride of lime ? 
The former is a definite compound, CaCl2, 
while the latter is a mixture containing calcium 
hypochlorite. Ca(CI0)2. 
567. Under wlialother name is chloride of lime 
known, and what are its properties and uses? 
Bleaching powder. The hypochlorite is very 
readily decomposed by acids, with evolution of 
chlorin, which then acts as a powerful bleaching 
and disinfecting. agent. When exposed to "the 
air, it is decomposed by the carbonic anhydrid 
contained therein. 
' 568. What are gypsum, terra alba, and plaster 
of Paris ? 
Gypsum is a native calcium sulfate, containing 
two molecules of water of crystallization, CaS04 
4- 2Aq. Terra alba is gypsum ground to a fine 
powder. When gypsum is heated the Aq is 
driven off. The remaining substance, CaS04, is 
plaster of Paris, and has the power of taking up 
water, when mixed with it, to form a hard, solid 
mass. 
569. W hat objection is there to the use of plaster 
in the ordinary way on walls of hospitals ? 
It forms a coating which is porous and uneven. 
In these pores and upon the projections various CHEMISTBY AND TOXICOLOGY. 
147 
deleterious organic substances collect to such an 
extent that, by scratching the surface of plaster 
in a hospital, a powder has been obtained con- 
taining as much as 46 per cent, of organic matter. 
570. How may this defect be remedied ? 
By adding to the ordinary mixture of plaster 
and water, used in plastering, a certain propor- 
tion of alum and gelatin, or of soluble glass. 
This mixture, on “setting,” forms a hard sur- 
face, which is then polished. 
571. Give the names and formulae of the phos- 
phates of calcium. 
Monocalcic phosphate, Ca(H2P04)a = acid cal- 
cium phosphate, superphosphate of lime. Di- 
calcic phosphate, Ca2(HP04)2. Tricalcic phos- 
phate, Caa(P04)» = tribasic or neutral phosphate 
of lime, bone phosphate, Calcii phosphas prseci- 
pitatus, U. S.; Calcii phosphas, Br. 
572. How does {POi)tCa3 exist in the animal 
economy ? 
It is the most abundant mineral ingredient of 
the body, and is found in every tissue and fluid, 
most abundantly in the bones and teeth. In the 
fluids it exists in small proportion, except in the 
milk, where it is found in comparatively large 
quantity (about 2f parts per 1,000). In the bones 
it is in combination (along with other mineral 
substances) with an organic substance, and upon 
the relative proportions of these two the rigidity 
and tenacity of the bone depend. 
573. How is “ bone black ” prepared, and what 
is its composition ? 
It is obtained by subjecting bones to a red heat 
without access of air. It is composed of carbon, 148 
ESSENTIALS OE 
tricalcic phosphate, and small quantities of other 
salts (calcic carbonate, trimagnesic phosphate, 
and calcic fluorid). By treating it with dilute 
hydrochloric acid the mineral substances are re- 
moved, and “ purified animal charcoal ” remains. 
574. How may pure tricalcic phosphate be ob- 
tained ? 
The impure salt, bone-ash, is acted on by HC1, 
when the soluble monocalcic phosphate and cal- 
cium chlorid are formed : 
Ca,(P04)2 + 4HC1 = Ca(H2P04)2 + 2CaCl2 
Tricalcic 
phosphate. 
Hydrochloric 
acid. 
Monocalcic 
phosphate. 
Calcium 
chlorid. 
Ammonium hydroxid is then added to the solu- 
tion, when pure tricalcic phosphate (Calcis phos- 
phas praecipitata, U. S. P.) is precipitated, and 
ammonium chlorid remains in solution : 
Monocalcic 
phosphate. 
CafH,P04), + 2CaCla + 4(NH4)HO = 
Calcium 
chlorid. 
Ammonium 
hydroxid. 
= Cas(P04)a + 4(NH4)C1 + 4H20 
Tricalcic 
phosphate. 
Ammonium 
chlorid. 
Water, 
575, W hat is ‘ ‘ superphosphate of lime ” ? 
An impure monocalcic phosphate, obtained by 
acting on bone-ash with sulfuric acid. It is used 
as a manure. 
576. In what parts of the body does monocalcic 
phosphate exist ? 
In brain tissue and in the acid fluids ; in the 
uriDe. This salt and the corresponding magne- CHEMISTRY AND TOXICOLOGY. 
149 
sium compound are known as “earthy phos- 
phates.” 
577. What mineral salts are sometimes deposited 
from the mine in calculi ? 
The earthy phosphates, i.e., tricalcic and tri- 
magnesic phosphates ; and ammonio-magnesian 
phosphate. 
578! What is the reaction of the urine during 
formation of a phosphatic calculus t 
It is alkaline, or at least markedly less acid 
than normal. 
(See Manual, pp. 200, 201.) 
579. In what forms does calcium carbonate occur 
in nature ? 
Exceedingly abundant as jrnarble, limestone, 
chalk, and calc spar, and in almost all natural 
waters and soils, in juices of plants, the shells of 
mollusks and Crustacea, bones, teeth, and animal 
fluids, coral and pearls. 
580. How is it prepared artificially, and by what 
name is it then known ? 
By adding sodic carbonate to solution of cal- 
cium chlorid. Ualcis carbonas prsecipitata. U. S., 
Br. : bTebtpitated chalk. 
~581 . W hat is prepared chalk ? 
It is native chalk ground to a fine powder and 
separated from all coarser particles by elutriation 
= Creta prseparata, U. S., Br. 
582, State the properties of calcium carbonate. 
An amorphous white powder, odorless, taste- 
less, very sparingly soluble in pure water, much 
more soluble in water containing carbon dioxid. 
When strongly is driven off and 
quicklime remains. 150 
ESSENTIALS OP 
588. What is the appearance of a mulberry cal- 
culus, and of what is it composed ? 
It is hard, dark brown or gray, sometimes 
smooth, usually nodulated or covered with short 
tubercles, soluble in HOI, and, when heated, 
blackens and finally leaves a white, alkaline resi- 
due. It consists mainly of calcium oxalate, 
CaC204. 
584. Describe the analytical reactions of the Ca 
compounds. 
1. With alkaline carbonates, a white precipi- 
tate, soluble in~IICI. " 
With ammonium oxalate, a white precipi- 
tate, soluble in HC1. 
3. With H2S04, a white precipitate, either 
immediately or on addition of two volumes of 
alcohol. 
585. What compound of barium is used in ana- 
lysis, and for what purpose? 
Barium chlorid, BaCl2, is used as a test for the 
presence of sulfuric acid or of a soluble sulfate; 
a white precipitate of barium sulfate, insoluble in 
nitric arid, is formed. 
586. What antidotes should be given in poison- 
ing by the soluble barium compounds ? 
Magnesium or sodium sulfate. 
BARIUM. CHEMISTRY AND TOXICOLOGY. 
151 
GROUP IV. MAGNESIUM GROUP. 
Magnesium Mg 24 
Zinc Zn 65 
Cadmium ... Cd 112 
587. Describe the common characters of the ele- 
ments of this group. 
Each forms a single oxid and a corresponding 
basic hydroxid fii" their salts they are always 
bWaTent. 
MAGNESIUM. 
588. Describe the properties of Mg. 
It is a silver-white metal, hard, light, and 
ductile. Tt burns in air with a brilliant wEile 
light and with formation of MtrO. It dissolves 
in dilute acids. 
~ 5«y (Jive the formula and common names of 
magnesium oxid. 
MgO Magnesia, U. S., Br.; Magnesia laevis; 
Magnesia usta: calcined magnesia. 
“590: State its properties. 
It is a very light, amorphous, white powder; 
infusible: very sparingly soluble in water. With 
HNOs, H2SO4, HC1 it forms the corresponding 
salt (Effervescence denotes contaminatipp, with 
magnesium carbonate.) 152 
ESSENTIALS OF 
591. W hat is ‘ ‘ milk of magnesia ” ? 
Magnesium hydroxid held in suspension in 
waterXFparTMgO to 10-20 parts'44aU). 
592. Under what other names is magnesium sul- 
fate known, and what is its formula ? 
Magnesii sulphas, U. S.; Magnesise sulphas, 
Br.; sulfate of magnesia; Epsom salts. MgS04. 
593. Give the characters of MgSOi. 
It forms colorless, transparent crystals, contain- 
ing 7 molecules of water of crystal 1 ization. Easily 
soluble in water, the solution being neutral. In- 
soluble in alcohol. 
594. W hat is triple phosphate, how is it formed, 
and of what pathological interest is it? 
It is ammouio-magnesian phosphate, (NH4) 
MgP04 + 6Aq. It is produced whenever a mag- 
nesium salt is brought in contact with an alkaline 
phosphate and an ammonium salt, the reaction 
being alkaline. In the urine, alkaline phosphates 
and magnesium salts are always present; hence 
when ammonia is produced by decomposition of 
urea, the conditions for the deposition of this 
Compound are fulfilled. Frequently it is deposited 
in the form of single, brilliant, tabular crystals. 
In some cases'it is slowly deposited, when it forms 
a “ fusible calculus.” 
595. How may a magnesium compound be de- 
tected in the presence of compounds of barium and 
calcium ? 
The barium and calcium compounds must be 
first separated thus: Add to the solution ammo- 
nium chlorid and liydroxid, then ammonium car- 
bonate ; the barium and calcium compounds are 
precipitated and removed by filtration.. To the CHEMISTRY AND TOXICOLOGY. 
153 
clear filtrate add solution of sodium phosphate; 
if magnesium be present, a crystalline precipitate 
of ammonio magnesian phosphate is formed. 
ZINC. 
596. For what purposes is zinc used ? 
In the manufacture of brass, which is an alloy 
of copper and zinc, and of German silver. “Sheet 
zincis zinc rolled out into thin plates: galvanized 
iron is sheet iron (or iron wire, etc.) covered with 
a thin coating of zinc. Galvanized iron and zinc 
should not be used in vessels intended To contain 
articles of food, as fatty matter, milk, and even 
water become rapidly charged with soluble zinc 
compounds when kept in vessels made of these 
substances. Zinc is largely used in galvanic bat- 
teries, and in the laboratory to obtain hydrogen. 
597. How is commercial zinc nearly always con- 
taminated ? 
With arsenic, iron, lead, and phosphorus. 
598. How is zinc oxid obtained? 
1. By subjecting zinc carbonate tojieat. The 
Zinci oxidum, U. S., Br~ 19 UllUTpfepared from 
the officinal zinc carbonate, which is a mixture 
of the true carbonate, ZnC03, and the hydroxid, 
ZnHaOa. 2. By burning metallic zinc in a cur- 
rent of air. This process is used on a large scale 
in the arts in the manufacture of “zinc white,” 
which is used as a pigment. 
599. State the differences between samples of zinc 
oxid prepared by the above processes. 
That prepared by 1 is of a pale-yellow color 
when cold, and yellow when hot, while that pre- 154 
ESSENTIALS OF 
pared by 2 is pure white and forms light, floccu- 
lent masses, whence it was formerly known as 
“Lana philosophica.” That prepared by 1 is 
liable to contain an excess of carbonate. 
600. State how zinc chlorid is obtained, and its 
properties. 
By dissolving Zn in HC1 and evaporating the 
solution. It is a'wEfte~solid, crystallizes with 
difficulty, and is very soluble in water. It com- 
bines readily with albuminoid substances. It is 
used medicinally as an escharotic" and for the 
preservation of anatomical material. 
601. Describe the action of zinc upon sulfuric acid. 
If both substances be pure, there is no action ; 
but if the acid be diluted with water, the zinc 
is dissolved, zinc sulfate and hydrogen result- 
ing. 
Pure Zn acts much less readily on H2S04 than 
when it is contaminated with other metals. In 
galvanic batteries, it is desii’able that the action 
between zinc and acid should only take place 
while the circuit is closed ; this end is attained 
by “amalgamating” the zincs, i.e., coating them 
with an amalgam of zinc and mercury. Plates 
so protected behave towards H2S04 like pure 
zinc. 
602. Why is zinc sulfate incompatible with vege- 
table astringents ? 
Because they contain tannic acid, with which 
the zinc salt forms an insoluble compound. 
603. Under what other names is zinc sulfate 
known, and what is its formula ? 
White vitriol, Zinci sulphas, U. S., Br. As 
usually met with its composition is ZnS04 -+- CHEMISTRY AND TOXICOLOGY. 
155 
7Aq; although it also crystallizes with 1, 2, 4, 5, 
6Aq. 
604. Describe the analytical reactions of the Zn 
salts. 
1. With ammonium sulfhydrate, a white pre- 
cipitate. 
2. With hydroxids of K, Na, or (NH4), white 
precipitates, soluble in excess. 
3. With potassium ferrocyanid, a white pre- 
cipitate. 
605. What preparations of zinc are liable to give 
rise to cases of poisoning? 
A strong solution of the clilorid with excess of 
acid used by tinsmiths. A disinfecting agent, 
known as Sir Wm. Burnett’s solution, composed 
of 230 grains ZnCl2 to the ounce of water. Zinc 
sulfate taken by mistake. 
606. What should be the treatment ? 
If the poison have not produced emesis, it 
should be induced. Milk, white of egg. or, better, 
some substance containing tannic acid, such as 
tea, infusion of bark, etc., should be given. 156 
ESSENTIALS OF 
GROUP VI. COPPER GROUP. 
Copper Cu 63 o 
Mercury Hg 20C7 
607. What is the valence of elements of this 
(jroup ? 
They are bivalent,. 
608. How many classes of salts do these elements 
form, and wherein do they differ ? ~ ~ 
Two. In one class a single atom of the element 
acts in its bivalent capacity, Cu", thus : Cu"S04 ; 
in the other class two atoms of the element, linked 
together, form a group which behaves like a single 
bivalent atom, thus: 
Cu " 
( I M or (Ou,r ; (Cua)0. 
MJu'' 
609. Explain the nomenclature of these com- 
pounds. 
Those compounds containing the single atom 
are designated by the termination ic, while those 
containing the double atom (Hga)" are 
designated by the termination ous. Thus CuO is 
known as cuprz'c oxid. and [Cu2)0 as cuprous 
oxid ; HgCU as mercurac chlorid. and (Hg2)Cl2 
as mercurows chlorid. The termination ous ap- 
plies Yo~that” compound containing the greater 
proportion of metal, while the termination ic CHEMISTRY AND TOXICOLOGY. 
157 
designates that containing the greater proportion 
Of the Other element or group nf elements • f7hns 
we have : 
Mercurcuw chlorid, Hg : Cl :: 2 :_2 
Mercuric “ Hg : Cl :: 1 : 2 
Cuprows oxid, Cu : O :: 2 :T 
Cupn'c “ Cu : O :: 1 : 1 
COPPER. 
610. How may pure copper be obtained? 
By decomposing cupric sulfate by means of the 
battery (electrotype). By heating cupric oxid in 
a current of hvd rogen. 
TO hat action takes place between copper 
and the mineral acids? 
Copper decomposes hydrochloric acid with 
difficulty, except when the metal is finely di- 
vided. 
Nitric acid is energetically acted on, nitrogen 
dioxid being given oft', and cutfTO*"nitrate re- 
maming in solution : 
8HNO3 + 3Cu = 3Cu(N03)2 + 4H30 + 2NO 
Nitric 
acid. 
Copper. 
Cupric 
nitrate. 
Water. 
' Nitrogen 
dioxid. 
Warm sulfuric acid, with copper, forms cupric 
sulfate, while sulfur dioxid is evolved : 
2HaS04 + Cu = CuS04 + 2H.0 + S02 
Sulfuric 
acid. 
Copper. 
Cupric 
sulfate. 
Water. 
SuTfur 
dioxid. 
612. What action takes place between copper and 
certain organic acids ? 
Many weak acids are decomposed, with forma- 158 
ESSENTIALS OF 
tion of salts of copper. When this metal is_&x 
posed to damp air it becomes coaled •with a green 
layer ol the carbonate Acetic acid (vinegarhJn- 
Cdritact with copper] forms the acetate. The 
fhtty acids also combine with the metal 
t 613. Givethe names and formula of the oxids 
of copper. 
Cuprous oxid. Cua.O. also known as red, or fjmh, 
oxid of copper ; cupric oxid, CuO, also known 
as' black, or protoxid.of,copper. 
61?.’ What decomposition takes place when cu- 
pric oxid and an organic substance are heated 
together, and how is this utilized ? 
The oxid gives nn its oxygen, which, uniting 
with the carbon and hydrogen of the organic 
substance, forms carbonic anhydrid and wafer] 
while metallic copper remains. This reaction 
afforcfiTus one of the best means of analytically 
determining the quantity of carbon and hydro- 
gen entering into the composiHorTof an organic 
compound. 
"'‘ 615? What is blue vitriol ? 
Cupric sulfate, CuS04. Cupri sulphas, U. S., 
Br. ; blue, stone. 
616. State its properties. 
Blue crystals with 5Aq; odorless; readily 
soluble in water, alcohol ; has a 
disagreeable, styptic taste. 'When heated, the 
Aq is driven off, and a white substance remains, 
which absorbs water and resumes its blue color 
witli great readiness. Its aqueous solution [s 
acid, and coagulates albumen. 
" 'GIT. Name some pigments containing Gu used 
in the arts, and give their composition. CHEMISTRY AND TOXICOLOGY. 
159 
Scheele’s green = mineral green = eunric 
ar senile!' Scnweinfurt green = mitis green = 
Faffs' green = cupric aceto-metariemte. Ver- 
digris = basic cupric” acetate. Mineral green, 
azurite or iTrmmtanrbtn'e, and blue ash = basic 
cu»rTccarbunatys4 
oHT the analytical characters of the 
cupric salts. 
1. With H2S, a black precipitate, insoluble in 
NH4HS, soluble in hot, dilute HN03. 
2. With KHO or NallO, pale-blue precipi- 
tates, insoluble in excess. 
3. With NH4HO, pale blue precipitate, form- 
ing dark-blue solution in excess. 
4. With potassium ferrocyanid, chestnut- 
brown -precipitate, insoluble in weak acids, de- 
colorized by KHO. 
5. With bright metallic Fe, in presence of an 
acid reaction, deposition of metallic Cu. 
619. How is copper poisoning usually occa- 
sioned f 
By the ingestion of sulfate or acetate of cop- 
per, or, more frequently, by eating food, pickles, 
etc., which have been cooked or allowed to 
stand in copper vessels. Occasionally in workers 
in the metal and by the use of articles of food 
adulterated with copper compounds. 
620. Does copper exist normally in the body? 
It does not. In analyzing bodies, traces of 
this metal are always found, without any history 
of its administration. This is, however, not 
“ physiological copper,” but has found its way 
into the economy with the food in small quanti- 
ties. Copper sulfate is frequently added to flour 160 
ESSENTIALS OF 
to render the bread white, and to canned vegeta- 
bles for the double purpose of “greening” and 
preserving them. 
621. What peculiarity is noticed in the vomit in 
copper poisoning ? 
*4i.It is blue or green in color. The green color 
due to copper may readily be distinguished from 
that produced by bile coloring matter by the 
addition of ammonium hydrate, which produces 
a deep blue color if copper is present. 
622. What treatment is indicated? 
The administration of albumen (raw white of 
egg), with which copper salts form an insoluble 
compound. Emesis or stomach pump. 
623. Give an easy clinical test for copper. 
Immerse a piece of iron (blade of a knife) into 
the fluid. If copper be present, it will be depos- 
ited in the metallic form. The addition of a 
little dilute HC1 or H2S04 hastens the formation 
of the deposit. 
MERCURY. 
624. Under what other names is this element 
known ? 
Hydrargyrum, U. 8., Br. ; mercurius ; quick- 
silver. 
625. Give its symbol, valence, and atomic 
weight. 
Hg (Latin, Hydrargyrum). It is bivalent. 
200. 
626. Of how many atoms is the molecule of mer- 
cury composed ? 
One. CHEMISTRY AND TOXICOLOGY. 
161 
627. What is the principal ore of mercury ? 
A native sal fid, known as cinnabar* 
628. (Jive iKe properties of elementary mer- 
cury. 
With the exception of bromin. it is the only 
element liquid at ordinary Temperatures. When 
dooled to —40° (—4C0 F.) it crystallizes, and 
when heated to 350° (662° F.) it boils ; it is vola- 
tile at all temperatures above —10°. It has a 
bright metallic lustre. Pure mercury remains 
unchanged in air at ordinary temperatures. It 
unites directly with chlorin, bromin. and iodin. 
629. What is an amalgam ? 
An alloy containing mercury. 
63UT"TF hat import an t pharmaceu tical prepara- 
tions contain elementary mercury ? 
Hydrargyrum cum creta, U. S., Br. = mercury 
with chalk; Massa hydrargyri, U. 8. = Pilulse 
hydrargyri, Br. = blue pill, blue mass; Unguen- 
tum hydrargyri, U. 8., Br. = mercurial ointment. 
631. What is the purpose of the chalk, confection, 
and lard in these preparations ? 
To “extinguish” the Hg—to convert it.into 
exceedingly minute globules which havejioAen- 
dency to unite! 
632. Has liquid mercury any chemical action on 
the economy ? 
It has not as long as it remains in that form. 
633. IIow is the mercury in the preparations 
named absorbed ? i 
In the manufacture of these preparations a 
notable quantity of the element is oxidized to 
mercurous oxid (a greater quantity in blue pill 
t.han in mercury with chalk); this, on contact with 162 
ESSENTIALS OF 
the acids of the gastric juice or perspiration, is 
converted into compounds which are soluble, and 
therefore capable of absorption. 
634. With what substances is commercial mer- 
cury contaminated? 
Lead, tin, bismuth, zinc, and mechanical im- 
puftttes. . 
635. What is meant by mercurous, and mercuric 
compounds ? 
Like copper, mercury forms two series of com- 
pounds, in one of which the single bivalent atom 
Hg enters; these are the mercuric compounds, 
and “contain the least proportionate amount of 
mercury. In the other, the double atom (tigs/' 
enters as a bivalent group; these are"the mer- 
cunras compounds. 
636. What is the formula of mercurous oxid ? 
Hg20. 
637. How is it formed, and what are its proper- 
ties ? 
By digesting mercurous clilorid with solution 
of potassa. It is aHi! acir~powcTer, odorless and 
tasteless; quite unstable"; formerly officinal as 
“ black precipitate.” 
63!T efive ine chemical name and forjpula of the 
other oxid of mercury. \ w 
Mercuric oxid, HgO. \ 
639. By what names is it known pharmaceuti- 
cally ? 
liydrargyri oxidum rubrum, U. S., Br.; Hy- 
drargyri oxidum flavum, U. S., Br.; red precipi- 
tate; red oxid of mercury. 
640. By what two processes is it prepared ? 
1. By heating mercuric nitrate as long as brown CHEMISTRY AND TOXICOLOGY. 
fumes are given off, and then washing with alco- 
hoT~and water: 12. By adding snlnfiondFcaustic 
soda to solution of mercnpe. c.hlariH 
641. W herein do oxias prepared by these processes 
differ from each other ? 
The oxid prepared by heat is crystalline, while 
the precipitated variety forms a yellowish-red, 
amorphous powder. The latter is much more 
active in its chemical and therapeutical properties 
than the former. 
642. Why does the ointment of this substance 
deteriorate on keeping ? 
Because, in contact with fats and certain other 
organic substances, the oYTd is decomposed, the 
organic matter being oxidized and metallic mer- 
’cury-Ttwiaiuliig. 
' 646. (Jive the formula and synonyms of mercu- 
rous chlffricf. 
Calomel; mild chlorid of mercury; 
Hydrargyri chloridum mite, U. S.; Hydrargyri 
subchloridum, Br. 
644. Oive an account of its preparation. 
Mercuric sulfate is first formed by heating to- 
gether mercury and sulfuric acid until a dry, 
white mass remains. This is then mixed with 
mercury and common salt, and again heated. 
HgS04 + Hg + 2NaCl = Na2S04 + Hg2Cla 
Mercuric Mercury. Sodium Disodic Mercurous 
sulfate. chlorid. sulfate. chlorid. 
The chlorid is volatilized and condensed in the 
upper part of the vessel, while the disodic sulfate 
remains. The chlorid is then washed with boil- 
ing water, until the washings no longer form a 
precipitate with ammonium hydroxid. 164 
ESSENTIALS OF 
645. With what substance is calomel liable to be 
contaminated ? 
With corrosive sublimate. 
646. How may this impurity be detected f 
By placing the powder upon a bright copper 
surface and moistening with water. If corro- 
sive sublimate be present, a silver-white stain is 
formed on the copper. 
647. Give the properties of mercurous chlorid. 
It is a heavy, white, amorphous powder; taste- 
less, odorless, insoluble in water. It distils with- 
out melting. When exposed to light, it is par- 
tially decomposed into mercury and corrosive 
sublimate: 
Hg.jCl8 = HgCla + Hg 
Mercurous 
chlorid. 
Mercuric 
chlorid. 
Mercury, 
This decomposition also takes place when mer- 
curous chlorid is boiled for some time with water, 
and, more rapidly in the cold, if the water con- 
tain alkaline chlorids. 
648. Why are the mineral acids incompatible 
with calomel ? 
Because of their tendency to decompose it, 
with formation of corrosive sublimate and a solu- 
ble salt of mercury with the acid. Nitromuriatic 
acid produces this decomposition most readily. 
649. Why are the alkaline chlorids, bromids, 
and iodids incompatible with calomel ? 
Because in their presence there is formation of 
the soluble mercuric chlorid, bromid, or iodid. 
It has been found in naval practice that the use 
of salt provisions precludes the use of calomel. CHEMISTRY AND TOXICOLOGY. 
165 
650. Why are the caustic and carbonated alka- 
lies incompatible with calomel ? 
Because in their presence mercurous oxid is 
first formed ; this is rapidly decomposed into 
mercurous oxid and mercury, and the former, in 
the presence of the alkaline chlorids of the gas- 
tric juice, is converted into corrosive sublimate. 
651. Give the formula and synonyms of mer- 
curic chlorid. 
HgCl2. Hydrargyri chloridum corrosivum, 
U. S. ; Hydrargyri perchloridum, Br. ; perchlo- 
rid of mercury; bichlorid of mercury; corrosive 
sublimate. 
652. Give the method of its preparation. 
By heating together mercuric sulfate and so- 
dium chlorid: 
IIgS04 + 2NaCl = HgCl2 + Na2S04 
Mercuric 
sulfate. 
Sodium 
chlorid. 
Mercuric 
chlorid. 
Disodic 
sulfate. 
The chlorid volatilizes, and is condensed in the 
upper part of the vessel—sublimes. 
653. State its properties. 
It forms heavy, white, translucent, crystalline 
masses, or, when pulverized, a pure white pow- 
der (calomel has a yellowish tinge), odorless. It 
has a strong, acrid, styptic taste, and is soluble 
in 16 parts of cold or in 3 parts of boiling water, 
also soluble in alcohol and in ether. The aque- 
ous solution is colorless and acid in reaction. It 
is decomposed by exposure to light, oxygen 
being given off, hydrochloric acid formed, and 
mercurous chlorid deposited : 166 
ESSENTIALS OF 
Mercuric 
chlorid. 
4HgCla + 2HoO = 2Hg2Cl2 + 4HC1 + 02 
Water 
Mercurous 
chlorid. 
Hydrochloric Oxygen 
acid. 
The decomposition is accelerated by the presence 
of organic matter. 
054. What is the action of lime water upon the 
chlorids of mercury ? 
With mercurous chlorid mercurous oxid is 
formed, and is then decomposed into a mixture 
of mercuric oxid and mercury ; this reaction 
takes place in the preparation of “ black wash.” 
Yellow wash is obtained in a similar manner 
with mercuric chlorid, and holds in suspension a 
yellow oxyclilorid. 
655. TF hat reaction takes place between mercuric 
chlorid and ammonium hydroxid ? 
A white precipitate is formed, which is re- 
garded as ammonium chlorid, NH4C1, in which 
two atoms of hydrogen are replaced by one atom 
of mercury, NH2Hg"Cl. This is the ammoniated 
mercury, or white precipitate, of the Pharmaco- 
poeia. 
656. Give the properties of the compound of mer- 
curic chlorid and albumen. 
When mercuric chlorid and albumen in solu- 
tion are brought together, a precipitate is formed 
which is insoluble in water, but is soluble in an 
excess of albumen, in dilute hydrochloric acid, 
or in solutions of alkaline chlorids. 
657. Give the formula and synonyms of mer- 
curous iodid. 
Hgnla. Hydrargyri iodidum viride, U. S., Br. ; 
protiodid, or green iodid of mercury. CHEMISTRY AND TOXICOLOGY. 
167 
658. State its properties. 
It is a greenish-yellow powder, odorless, taste- 
less, very sparingly soluble in water. It is very 
readily decomposed into mercuric iodid and mer- 
cury. 
659. Give the formula and synonyms of mer- 
curic iodid. 
Hgl2. Hydrargyri iodidum rubrum, U. S., 
Br. ; red iodid, or biniodid of mercury. 
660. State its properties. 
When first formed it is yellow, but rapidly be- 
comes scarlet. It is tasteless, odorless, permanent 
in air, sparingly soluble in water, but quite sol- 
uble in solutions of the chlorids, bromids, or 
iodids. 
661. W hat officinal preparation of arsenic con- 
tains mercuric iodid? 
Liquor arsenii (sic) et hydrargyri iodidi, U. S. 
P., commonly known as Donovan’s solution. 
662. What is vermilion ? 
Mercuric sulfid, HgS, prepared artificially. 
663. What is the composition of turpeth mine- 
ral? 
It is a basic mercuric sulfate, i.e., mercuric 
sulfate comb ned with the oxid : HgS04,2Hg0. 
664. Give the analytical characters of the mer- 
curous salts. 
1. With HC1, a white precipitate, turns black 
with NH4HO. 
2. With H2S, a black precipitate, insoluble in 
N1LHS, HN03, or HC1. 
3. With KHO, black precipitate, insoluble in 
excess. 
4. With KI, greenish precipitate. 168 
ESSENTIALS OP 
665. Give the analytical characters of the mer- 
curic salts. 
1. With HjS, a precipitate, at first white, then 
orange, finally black. 
2. With KHO or NaHO, yellow precipitate. 
3. W ith NH4HO, white precipitate. 
4. With KI, yellow precipitate, rapidly turn- 
ing salmon-colored and red, forming colorless 
solution with excess of precipitant. 
5. With stannous chlorid, white precipitate, 
turning gray, and depositing globules of Hg 
when the liquid is boiled. 
666. How may Hg be best detected in the urine in 
cases of suspected poisoning ? 
By the application of the Reinsch test (see Q. 
345-348). 
Or a small bar of Zn, around which a strip of 
dentists’ gold foil has been spirally wound, may 
be immersed in the urine, acidulated with H2- 
S04. In the presence of Hg the Au is dimmed 
in 24 hours, and if it be washed, dried, and 
heated in a tube, a sublimate is formed, which 
consists of microscopic globules of Hg. 
667. What kind of mercurials are capable of 
causing poisoning ? 
All compounds soluble in water or in the di- 
gestive liquids. 
668. II hat compound of Hg is most frequently 
the cause of poisoning ? 
Corrosive sublimate. 
669. Describe the prominent symptoms of acute 
corrosive sublimate poisoning. 
The nauseous, metallic taste is experienced 
during the act of swallowing. Within a few CHEMISTRY AND TOXICOLOGY. 
169 
moments this is followed by an intense, burning 
pain in the mouth, throat, and stomach. The 
mouth and tongue are whitened and shrivelled. 
There are vomitings of a white material, contain- 
ing shreds of mucous membrane, and tinged with 
blood, and bloody stools. Salivation occurs if 
life be sufficiently prolonged. Death sometimes 
occurs early from collapse, accompanied by con- 
vulsions, or in deep coma ; but in most fatal 
cases life is prolonged for from three to six days. 
670. What are the points of diagnosis between 
arsenical and mercurial poisoning f 
Arsenical Poisoning. 
1. The symptoms 
rarely begin within 20 
minutes. 
2. Pain is usually 
limited to the stomach 
and throat. 
3. The taste is very 
faint, sweetish, and me- 
tallic. Usually none. 
4. The mouth and 
tongue are normal. 
5. The urine contains 
As. 
Mercurial Poisoning. 
1. The symptoms be- 
gin almost immediately. 
2. Pain is also severe 
in the mouth. 
3. The taste is in- 
tensely metallic, and 
nauseous. 
4. The mouth and 
tongue are whitened 
5. The urine contains 
Hg. 
671. Give the antidote for corrosive sublimate 
poisoning. 
White of egg. The following precautions 
should be observed in its administration Too 
much should not be given at one time, lest the 
precipitate be dissolved in the excess; the anti- 
dote should be followed by an emetic, to remove 170 
ESSENTIALS OP 
the precipitate before it shall have been dissolved 
by the acid and chlorids of the gastric juice. 
672. Describe the post-mortem appearances in 
poisoning by Jig Cl. 
The salivary glands are enlarged. The tongue, 
mouth, oesophagus, and mucous membrane are 
usually shrivelled, and grayish-white in color, 
though sometimes they are reddened and intensely 
inflamed. The intestines are usually highly con- 
gested and the urinary bladder contracted and 
empty. CHEMISTRY AND TOXICOLOGY. 
171 
COMPOUNDS OF CARBON. 
673. Tinder what other name are these com- 
pounds known? 
Organic substances. 
674. What is the distinction between organic 
and inorganic substances? 
Any compound containing carbon is an organic 
compound, whether it be a constituent of a vege- 
table or animal body, or not. The division is 
simply one of convenience, and is retained owing 
to the great number of the carbon compounds. 
675. What are the valence, symbol, and atomic 
weight of carbon ? 
It is bivalent and quadrivalent, its symbol is C, 
and its atomic weight 12. 
676. Of what four elements are organic com- 
pounds principally composed ? 
Carbon, hydrogen, oxygen, and nitrogen. 
677. What elements may enter into the composi- 
tion of organic compounds ? 
All the elements. 
W hat property do the atoms of carbon pos- 
sess to an extraordinary degree, and what bearing 
The power oTcombming with each other and 
interchanging valences, which thus equalize each 
other and dfsappea'r. Were it not for this prop- 
erty of carbon, the number of its compounds 172 
ESSENTIALS OF 
would be very much smaller than it is. We could, 
for example, have but one saturated compound 
of carbon with hydrogen, ClvII4; we have, how- 
ever, a large number of such compounds, the 
constitution of some of which may be thus repre- 
sented : 
679. What is an homologous series ? 
A series of compounds, each term of which 
differs'frorhTKS nekt b‘y CHa, more or less, 
The members of the same series are possessed 
of similar properties. —■ 
680. What is a general or algebraic formula? 
An algebraic formula applicable to an entire 
homuluguuirseries. Thus the general forinuTaTof 
the substances mentioned in Q. 678 is CnHsiT+"a, 
and from this formula that of any member of the 
group may be deduced, if its position in the series 
be known. If, for example, the formula of the 
5th in the series be required, n = 5, and we have_ 
X 2) + 2 Or C»Hia. 
*681. W hat are isomeric bodies ? 
Substances different in their nature and proper- 
ties, but having the same percentage composition. 
“Thus acetic acid arid methyl formate, although 
entirely distinct substances, endowed with..very- 
different properties, consist each of C—40 ; Or 
58.33; and H—6.67 parts in 100. CHEMISTRY AND TOXICOLOGY. 
173 
682. How many kinds of isomerism are recog- 
nized, and how are they designated ? 
Two. Metamerism and Polvmerisrm 
688. Wfien are Two substances said to be meta- 
merio ? 
' wnen they have the same percentage compo- 
sition and also the same molecular weight. Thus 
methyl formaTe'amT acetic acid are metameric 
because they each have the percentage*c5mposi- 
tion given in Ans. 681, and the molecular weight 
of each is 60. 
" 684: When are substances said to be polymeric ? 
When they have the same percentage composi- 
tion, but the molecular weight of one is a multiple 
of the molecular weight of the other. Thus me- 
CTTyT formate and acetic acid are polymeric with 
glucoseTbecause each has tlie percentage composi- 
tion given in Ans. 681; but, while the molecular 
weight of the former two is 60, that of the last is 
180, or 60 x 3, its formula <R6ingC«Hi30«. 
685. To what are, the differences in properties of 
isomeric substances due ? 
To different arrangement of the atoms, different 
structure of the molecules.'"' 
636. What is understood by the terms cornjmi- 
tion and constitution ? 
The composition of a substance is the number 
and kind of atoms of which its molecule consists. 
Its Constitution is the intimate structure of the 
molecule; the relations of the atoms to each other. 
687. What are 'empirical'formulae? tr'’ 
Formulae indicating the composition of a sub- 
staTICSI T5uT“not its constitution, as : “H2S04, 
c2k4o2. 174 
ESSENTIALS OF 
688. W hat is a radical f 
A group of atoms capable of passing unaltered 
from one compound to another, and in this be- 
having like an atom. 
ExaffipW:—"EgrtTrconsider the compound CH4 
as composed of CH3H ; if we act upon this with 
iodin we obtain a compound CHSI ; if we now 
treat this substance, under proper conditions, 
with potash, we obtain a compound CHsOH ; 
and if we act upon this with acetic acid we ob- 
tain a compound CH3,C2H.302. This group CH3 
is, therefore, capable of passing from one com- 
bination to another without undern-ding-change 
itseli ; _iFTs a radical. As it is composed of one 
atom of the quadrivalent carbon, three of whose 
valences are satisfied with atoms of hydrogen, 
there remains one free valence, 
and the radical behaves like an atom of 
an univalent element (CH3)'. 
689. What are meant by types ? 
Common substances, the arrangement oi the 
atolhS’m wHbSff Tnblecules may be taken as’repTe'-— 
tentative of whole classes of other substances 
whose molecules have a similar arrangement. 
d0O‘. Under what' UvreeTypes may organic sub- 
stances be classified ? 
Hydrogen, water, and ammonia. The mole- 
cul®sT5f',5ydfogeh consists ~oT two atoms united 
together, thus : j-. The molecule of water is CHEMISTRY AND TOXICOLOGY. 
175 
composed of two atoms of hydrogen (univalent) 
united to one atom of oxygen (bivalent), thus : 
/TT TJ \ 
O \H’or H f O’ The molecule of ammonia 
consists of three atoms of hydrogen united to 
one atom of nitrogen (trivalent). Under these 
three types (either singly or combined with each 
other) organic substances, whose constitution ia 
known, can be classified. 
Hydrogen 
Type. 
Water 
Type. 
Ammonia 
Type. 
H 
H 
ifo« 
H) 
H [ N'" 
H 
(CH ,) 
H 
(CH^ 
(CH3)' ) -»T//( 
(ho. r 
Marsh gas. 
Wood spirit. 
Methylamin, 
691. What are typical formulae ? 
Formulae partially indicating the constitution 
of tne substance, ana constructed by the substi- 
tution of a radical or radicals in one of the three 
types, or a combination of two of them. Thus 
' Choi 
the typical formula of acetic acid is 2 j- O, 
while that of methyl formate is | O. 
692. What is a graphic formula ? 
A formula showing the constitution of the 
substance completely,, the relations of all of 
the atoms. Thus the graphic formula of acetic 176 
ESSENTIALS OP 
acid is 0=C—O—H, while that of methyl form- 
ate is 0 = C—O—C=HS. For the sake of brevity 
H 
these formulae are usually written CHS—CO,OH 
and H—COO,CH3. It is obvious that the gra- 
phic formula of a substance can only be con- 
structed when its constitution is known. 
693. W hat is a hydrocarbon ? 
A compound containing only carbon and 
hydrogen. 
694. How are organic substances classified ? 
The different series of hydrocarbons form the 
skeleton of file classid cation. Other orgUfiic 
substances are considered as derived from them 
by substitution of atoms or radicals for atoms of 
hydrogen or carbon. These derivatives are ar- 
ranged in groups, the members of which have 
the same chemical nature, or' function 7 as acids. 
alcohols, eThets, etCT1 
695. Into what two classes are the hydrocarbons 
divided, and wherein do they differ ? 
The oven chain'or acyclic, and the closed chain 
or cyclic. The former contain two terminal car- 
bon atoms attached to but one other carbon atom, 
as in the formula given in Ans. 678. In the 
latter every carbon atom is attached.Jo at least 
two others, as in I. below. There also exist 
hydrocarbons formed by the union of acyclic 
with cyclic hydrocarbons or their derivatives, as 
in IL Iff these the attached acyclic portion is 
designated a lateral chain. CHEMISTRY AND TOXICOLOGY. 
696. Name and give graphic formula of the 
three series of acyclic hydrocarbons. 
I. The Paraffin or Methane series, the formula 
of onejaTWETEffis: Ctf3—TTH^CH..—Clla. 
~TTr7The 'Otfjtft or 'Ethene series, the formula of 
one of which is: CHa—CH—'C5a—CH3. 
~ ill. 'l’he Acetylene or EthvFtV series,~ tire for- 
mula of one of whicTi is : CHX—C112—C 13 3 178 
ESSENTIALS OP 
ACYCLIC HYDROCARBONS. 
SATURATED HYDROCARBONS. CnH-m -f 2. 
Paraffin or Methane Series. 
697. What is a saturated compound ? 
One in which all the possible valences of the 
constituent elements are satisfied, as in ClvH'4. 
698. What name is applied to the members of 
this series, and why ? 
Paraffins, from parum = little, and affinis = 
affinity f because they "are substances which have 
little tendency to enter into chemical reaction. 
699. What is the composition of the radical 
methyl ? 
CH3. 
700. What does the termination yl indicate ? 
That the name refers to a radical. Thus 
methyl, CH3; hydroxyl, OH; acetyl, C2H30, etc. 
701. Give the formula and synonyms of methyl 
hydrid ? 
CH4. It is also known as Marsh gas, fire 
damp, light carburetted hydrogen. 
702. Describe its properties. 
It is a colorless, odorless, tasteless gas, lighter 
than air, sparingly soluble in water ; burns with 
a yellow flame; forms explosive mixtures with 
air and oxygen. A large quantity of carbon di- 
oxid is formed in an explosion of such a mixture, 
and is known to miners as “ after-damp.” 
708. What natural product is composed mainly 
of saturated hydrocarbons ? 
Petroleum. [The terms of this series vary CHEMISTRY AND TOXICOLOGY. 
179 
regularly as to their boiling point, from the low- 
est, which is gaseous at ordinary temperatures, to 
the 16th, which only boils at about 280° (536°F.). 
A petroleum is liable to explode in proportion as 
it contains hydrocarbons of low boiling point.] 
704. Name some of the products obtained from 
petroleum. 
Petroleum ether or rhigolene, gasolin, benzin, 
kerosene, lubricating oils, paraffin, vaselin. 
705. What are the properties and uses of petro- 
leum ether ? 
It is a colorless liquid, sp. gr. 0.7, highly in- 
flammable, boils at 21° (70° F.). It is used as a 
substitute for sulfuric ether to produce cold by 
its rapid evaporation, and asjksaLygnt. 
706. WhaftTrTThc properties and uses of paraffin ? 
It is a white, crystalline solid, fusible at 45°- 
65° (113°-149° F.), used in the manufacture of 
candles and to protect glass and other surfaces 
from the action of acids, alkalies, etc. 
707. What is vaselin, and whafare its proper- 
ties and uses ? ~~ 
It is a mixture of paraffin with lubricating oils. 
It varies in consistence according to tKePpropor- 
tions of the constituents, but has usually the 
consistence of butter. It is acted upon by chemi- 
cal agents with great difficulty. It is used in 
pharmacy (Petrolatum, U. S.) and in perfumery 
for the purposes formerly served by the animal 
fats, over which it has the advantage of never 
becoming- rancid. 
HALOID DERIVATIVES OF THE PARAFFINS. 
708. W hat is understood by substitution ? 
The replacement of an atom or atoms of one 180 
ESSENTIALS OF 
element for an equivalent number of atoms of an- 
other element in a compound. Example : The 
compound CH4 being saturated, it is impossible 
to introduce any other atom into its molecule 
without, at the same time, displacing therefrom 
one or more of its atoms. Acting upon CH4 
with chlorin, it is possible to remove each of the 
atoms of hydrogen and substitute therefor atoms 
of chlorin, forming the substituted compounds 
CHsCl ; CH2C12 ; CHC13; CC14. < — 
709. What important substance results from the 
substitution of three atoms of chlorin for atoms of 
hydrogen in methyl hydrid? 
Chloroform, which is chlorid of bichlorinated 
methyl, °H01. |. 
710. State its physical properties. 
It is a colorless, volatile liquid, having an 
agreeable, ethereal odor, anTl a sweet taste. It is 
heavier than water, with which“Tf3Toes not mix ; 
it mixes in all proportions with alcohol and 
ether. It boils at 60°.8 (141 aA F.). It can only 
be ignited with difficulty. It is a good solvent 
for fats, gutta-percha, and many substances rich 
in carbon. 
7Yl.wHow is chloroform tested for impurities? 
When used for inhalation it should respond to 
the following tests : Its sp. gr. should be 1.49. 
When shaken with an equal volume of colorless 
H2S04 the mixture should not become hot, and 
after twenty-four hours the upper (CHC13) layer 
should be absolutely colorless, while the acid 
layer should have only a pale yellow tinge. 
When thrown upon H20 it should sink in trans- 
parent drops, and the water should not become CHEMISTRY AND TOXICOLOGY. 
181 
milky. When evaporated, the last portions 
should have no pungent odor, and the remaining 
film of moisture should have no taste or odor 
other than that of chloroform. 
712. How may. C1IC13 be detected ? 
With alcoholic solution of KHO and a few 
drops of anilin it gives off a disagreeable odor, 
resembling that of witch hazel, when heated. 
(See Manual, pp. 234, 235.) 
713. How are bromoform and iodoform related 
to chloroform ? 
They have the same constitution, bromin or 
iodin replacing the chlorin: 
CHC1* > 
Cl \ 
Chloroform. 
CHBr, ) 
Br f 
Bromoform. 
Iodoform. 
CHI, ) 
714. State the principal properties of iodoform. 
It forms yellow crystals, having a strong, dis- 
agreeable odor. Insoluble in water, soluble in alco- 
hol. It contains 96 pergent. of its weight of iodin. 
MONO ATOMIC ALCOHOLS. 
715. What is an alcohol ? 
A hydroxid containing a hydrocarbonradical 
ancricapable of reacting with an acid_to procTuce a 
compMTRl ether (see Q. 757) and water. 
"The alcohols are the counterparts of the metal- 
lic hydroxids, while the compound ethers are the 
counterparts of the metallic salts. 
'716. Who f'is meant by the atomicity of an al- 
cohol? 
The saturating power of its radical. Thus 
(C3Ht) j. o is a monoatomic alcohol ; 182 
ESSENTIALS OP 
(C H )" ) 
V IT [ 02 is a diatomic alcohol, and 
(C H Y,A ) 
' v 03 is a triatomatic alcohol. 
717. What group of atoms is characteristic of 
primary alcohols, and what are their products of 
oxidation ? 
CH2OH. Their products of oxidation are: 
first, an aldehyde, and, by more complete oxida- 
tion, an acid containing the same number of car- 
bon atoms as the alcohol. Thus the primary 
CHsOlI 
alcohol | yields by oxidation, first the 
CH3 
CoH COOH 
aldehyde | and then the acid | 
'— ch3 ch3 
718. What group of atoms is characteristic of a 
secondary alcohol, and what is produced from it by 
oxidation ? 
CHOH. A ketone or acetone. Thus the 
K CH3 
I 
secondary alcohol CHOH produces the ketone 
I 
CH3 
ch3 
I 
CO by oxidation, 
I 
CH3 
719. What group of atoms is characteristic of a 
tertiary alcohol, and what are its products of oxi- 
dation ? CHEMISTRY AND TOXICOLOGY. 
183 
COH. When oxidized, it produces two acids 
or ketones, each containing a less number of car- 
bon atoms than the original alcohol. 
(See Manual, pp. 237-240.) 
720. Give the empirical, typical, and graphic 
formulae, and the names of methyl hydroxid. 
f'TT f) • PIT ) CII2OM. 
’ u O; I Methylic alcohol, 
11 > H. 
wood alcohol, pyroxylic spirit, carbinol. 
721. From what source is methyl alcohol obtained 
commercially ? 
It is one of the products of the distillation of 
wood. 
722. What is methylated spirit? 
Spirits of wine containing ten per cent, of wood 
spirit. This does not interfere with its use in the 
arts, but communicates a disagreeable taste and 
odor which prevent its being taken internally. 
723. Give the empirical, typical, and graphic 
formulae, and the names of ethyl hydroxid. 
fl IT A . TT I CH2OH. 
°atl*U > j. O; | Ethylic alcohol, 
CH3. 
vinic alcohol, alcohol, spirits of wine, methyl 
carbinol. 
724. From what substance is alcohol usually ob- 
tained ? . 
From starch. 
725. Describe briefly the method of obtaining al- 
cohol from starch. 
The process is divisible into three parts: 1. The 
Sain is malted, i.e.. itjis caused to.germinate. In 
is stage"o? the process, a peculiar substance, 
called diastase, is produced, which causes the 184 
transformation of starch into glucose. 2. The 
saccharine liquid is brought in contact with yeast, 
a plant whose nutrition is attended with fermen- 
tation, by which glucose is decomposed into alco- 
hol and carbon dioxid: C8Hi206=2C2He0 + 2C02. 
3. The alcohol is more or less perfectly separated 
from other substances by distillation. 
72G. Explain the difference between the various 
kinds of ethyl alcohol used in the arts and in 
pharmacy. 
They differ from each other mainly in the pro- 
portion of alcohol and water. 
Absolute alcohol is pure alcohol, C2H60. [It is 
obtained with difficulty, and deteriorates rapidly, 
owing to its great tendency to absorb water. The 
so-called absolute alcohol of the shops is seldom 
stronger than 98 per cent.] 
Alcohol, U. S.—Stronger alcohol. Has a spe- 
cific gravity of 0.820, and contains 94 per cent, 
alcohol. Spiritus rectificatus, Br., sp. gr. 0.838, 
contains 84 per cent, of alcohol. 
Alcohol dilutum, U. S. — Spiritus tenuior, Br., 
is of sp. gr.0.920, and contains 53 percent, alcohol. 
Proof spirit—Spirits of wine—contains 49 per 
cent, alcohol. 
727. State the principal properties of alcohol. 
It is a colorless, mobile fluid, having, when 
pure, specific gravity 0.794, and boiling point 78° 
(172°.5 F.). It lial a peculiar odor and a sharp, 
burning taste; very volatile. It has a great at- 
traction for water, and to this are due its coagu- 
lating action on albumen and its preservative 
action on animal substances. It is a very useful 
solvent. 
ESSENTIALS OF CHEMISTRY AND TOXICOLOGY. 
185 
728. What is the alcoholic strength of “ spiritu- 
ous liquors ”? 
From 58 to 56 per cent, absolute alcohol 
729. Mention the sources of some of the principal 
spirits. 
Brandy (Spir. vini Gallici, U. S., Br.) is ob- 
tained by distilling wine. Rum, by fermenting 
and distilling molasses. American whiskey, 
Spiritus frumenti, U. 8., from rye, wheat, or In- 
dian corn. Irish and Scotch whiskey, from 
barley. [The peculiar smoky flavor is produced 
by drying the grain over a peat fire.] Gin is 
obtained from various grains, and is flavored 
with juniper berries. 
730. Wherein do wines differ from spirits ? 
In that they contain a smaller proportion of 
alcohol, and, as they are not distilled, in con- 
taining a variety of solid substances, present in 
the juice of the grape, which do not exist in spir- 
its. 
731. What is the alcoholic strength of “light” 
wines ? 
From 7 to 14 per cent. 
732. Of heavy wines ? 
From 14 to 21 per cent. 
733. What is the alcoholic strength of mylt 
liquors ? 
From H to 9 per cent. 
(See Manual, pp. 245-248.) 
734. Describe the various products of the oxida- 
tion of alcohol. 
These vary according as the oxidation is rapid 
or slow. If the oxidizing agent be energetic, as 186 
ESSENTIALS OF 
chromic anhydrid, the alcohol burns, and jsjcon- 
verted into carbon dioxTd and water : 
Alcohol. 
CsHbO + 302 = 2C02 + 3H20 
Oxygen. 
Carbon 
dioxid. 
Water. 
If the oxidation take place more slowly, it is 
lmnted'TST.K'fe'substitution of an litom of oxygen 
for two of hydrogen, forming acetic acid : 
Alcohol. 
C2HeO + 02 = C2H402 + H20 
Oxygen. 
Acetic acid. 
Water. 
If the action take place still more slowly, alde- 
hyde is formed : 
Alcohol. 
2C2H,0 + 02 = 2C2H40 + 2H20 
Oxygen. 
Aldehyde. 
Water. 
For tests for alcohol, see Manual, pp. 243, 244. 
735. Give the formula and synonyms of amyl 
liydroxid. 
j. o. Amyl alcohol, fusel oil, grain oil, 
potato spirit. 
The composition of “fusel oil” varies with 
the different spirits, and contains propylic, buty- 
lic, and hexylic alcohols as well as amylic. 
736. W hut practical interest attaches to it ? 
It is produced in small quantities along with 
varying quantities of propyl, butyl, and hexyl 
alcohols, in alcoholic fermentation, and, as it 
has deleterious properties, must be carefully 
separated from the spirits. The separation is, 
however, never complete, nor should it be, as the 
substances to which a properly aged spirit owes CHEMISTRY AND TOXICOLOGY. 
187 
its flavor are formed bv the gradual oxidation of 
these alcohols. ~ ’ I J 
SIMPLE ETHEKS. 
737. What substance is formed by substituting 
for the remaining extraradical hydrogen of alcohol 
the radical ethyl ? 
Oxid of ethyl, or ethylic ether, j- O = 
ChHi.iQ. commonly known as “ sulfuric ether.” 
73o. To what substances does the name ether 
apply ? 
To all substances produced by the action of an 
acid upon an alcohol. 
T6M.W hat are simple, mixed, and compound 
ethers? 
Simple and mixed ethers are oxids of the alco-, 
holic radicals, the radicals being the same in the 
simple ethers and different in the mixed ethers. 
Compound ethers are acids in whlcli tlie livdTo- 
gen has been replaced by hydrocarbon radicals. 
Thus j- O is a simple ether, j- O a 
n tj O ) 
mixed ether, and qjj j- O a compound ether. 
740. Why is the name '‘sulfuric ether” im- 
proper as applied to ethyl oxid t 
Because it contains no sulfur. The name 
properly applies to another substance: 
IjC^H2) i It s^ be calle(! ethylic ether. 
741. Describe the manufacture of ether. 
A mixture of H2SO4 and alcohol is maintained 188 
ESSENTIALS OF 
at a temperature of 140° (284° F.), in a retort into 
which flows a slow, but constant, stream of al- 
cohol, and which is connected with a suitable 
condenser. The first distillation yields a mix- 
ture of C4Hi0O, C2H80, and small quantities of 
H2SO«. To purify the ether, this mixture is 
shaken with milk of lime and EL>0. Upon 
standing, the ether, purified from H2SQ4 and 
D2tL«0, rises to tiie surface and is decanted. 
This product is known as “ washed ether,” and 
still contains H20, which is removed by the ad- 
dition of calcium oxid and redistillation. As 
thus purified, it lorms the .Ether fortior. IT. S.: 
-dSther purus. Br. 
742. Explain the conversion of alcohol into ether. 
A small quantity of H2S04 is capable of etheri- 
fying a large quantity of C2H60. This was 
one of the processes formerly explained (?) by 
the empty word “catalysis.” One molecule of 
H2S04 and one of C2H80 first act upon each 
other, the ethyl of the C2H60 replacing an atom 
of hydrogen of the acid, with formation of a 
substance called sulfovinic acid : 
C2H8> 0 , S02 ) n _ S02) R, 
H [° + H2}°* “ H to, + 5[° 
(C2H8) 11 > 
Alcohol. 
Sulfuric 
acid. 
Sulfovinic 
acid. 
Water. 
As soon as the sulfovinic acid is formed it reacts, 
molecule for molecule, with alcohol, giving up 
again the radical ethyl, which replaces the extra- 
radical hydrogen of the alcohol, while H3S04 is 
regenerated : CHEMISTRY AND TOXICOLOGY. 
189 
SH°’U + (C.H.)|0 _ (SO.) )0,+ 
(CaH6)j H > “ 02 > 
Sulfoviuic 
acid. 
Alcohol. 
Sulfuric 
acid. 
, (CaH.)')0 
+ (C2H6)'Cu 
743. State the properties of ethylic ether. 
It is a colorless, mobile liquid, having a pecu- 
liar and tenacious odor ; it is lighter than H20, 
in which it is only slightly soluble. It boils at 
35° (95° F.) at ordinary barometric pressure, and 
is very volatile at all temperatures. It is highly 
inflammable, and its vapor forms an explosive 
mixture with air. It is an excellent solvent of 
fats, resins, alkaloids, etc. 
744. What precautions are to be observed to 
guard against ignition of ether ? 
That it be used at a distance from lights and 
fires. The vapor of ether is heavier than air, and 
more danger is therefore to be apprehended from 
a grate fire than from a chandelier. In admin- 
istering ether at night, the light should be held 
well above the patient. 
Ether. 
MONOBASIC ACIDS. CnH2n02. 
745. Explain the formation of the monobasic 
acids from the corresponding alcohols. 
They are produced by the substitution of an 
atom of oxygen for II2 in the group utijOH 
of the primary alcohol1. Thus the graphic iormu- 
lse of ethylic alcohol and acetic acid are: 190 
ch2oh 
I 
ch3 
ESSENTIALS OP 
COOH 
ch3 
746. What group of atoms is characteristic, of 
organic oxyacids ? 
COOH. The basicity of the acid depends 
upon the number of such groups which it con- 
COOH 
tains. Thus acetic acid, I , is monobasic ; 
CH3 
COOH 
oxalic acid, | , is dibasic, etc. 
COOH 
747. Under what other name is the senes of 
monobasic acids known, and why ? 
The volatile, fatty acids. So called because 
theHmvW 11 ibmbers are volatile liquids, while the 
higher terms are important constituents of the 
animal fats. 
748! What acid of this series is obtained from 
ethylic alcohol ? 
COOH 
Acetic acid = | = Acidum aceticum, 
CH3 
U. S., Br. 
749. How is the pure acid designated, and what 
are its properties ? 
Glacial acetic acid ; Acidum aceticum glaciale, 
U. ST, Br. A colorless liquid, which solidifies to 
an ice-like mass at 17° (62°.6 F.), and boils at 
119° (246°.2 F.). It has a pungent odor and a 
pure acid taste and acid reaction. It attracts 
moisture from the air, and should be kept in well- CHEMISTRY AND TOXICOLOGY. 
191 
closed bottles. The commercial acid usually con- 
tains about 35 per cent. (j2tt402. 
75TT \\ nat is the composition of vinegar, and 
how is it obtained ? 
It is dilute acetic acid, holding in solution the 
soluble constituents of the liquid from which it is 
obtained, it is prepared by the oxidation ot' some 
substance containing alcohol, as wine7cider7 or 
of malt, as a result of the processes of 
nutrition ot ah organized ferment, known as 
mother of vinegar or mycoderma aceti. 
751. What are the salts and ethers of acetic acid 
called, and wha t is their'-ioMlUillidn? * 
Acetates. Acetic acid is monobasic, therefore 
acetates of the univalent metals and radicals have 
the constitution : 
COOK 
I 
ch3 
COO(C2H6) 
I 
CH* 
Potassium acetate. 
Ethyl acetate. 
while those of the bivalent metals are formed by 
one atom of the metal replacing the hydrogen of 
two molecules of acid ; 
CH3 
°°°\pb" or Pb(C2H302)2 
I 
CH3 
752. Where does butyric acid occur in nature ? 
In milk and batter in combination ; also in the 
Lead acetate. 192 
ESSENTIALS OP 
perspiration, muscular fluid, contents of the in- 
testine, and in the products of putrefaction. 
753. Explain the formation of free butyric acid 
in the intestine. 
It is formed in part by the decomposition of 
butyrates contained in certain fats, but the 
greater quantity has its source from the saccha- 
rine elements of food, which are, to a certain ex- 
tent, first converted into lactic acid, and this into 
butyric acid. 
754. Give the formula, occurrence, and method 
of artificial preparation of valerianic acid. 
n o a ) 
6 IT C O. It occurs in valerian root, but is 
more easily obtained by the oxidation of amylic 
alcohol: 
| o + 02 = J. o + h2o 
Amyl 
hydroxid. 
755. What valerianates are officinal ? 
Those of sodium, ammonium, zinc, and qui- 
nin. 
756. What other acids of this series occur in 
combination in the animal economy ? 
Caproic, C6Hn,COOH; caprylic, C7Hi5,COOH; 
capric, CaHi9,COOH ; myristic, Ci3H27,COOH; 
palmitic, CioHsi.COOH ; and stearic, C17H35,- 
COOH. , 
Oxygen. 
Valerianicr 
acid. 
Water. 
757. What is a compound ether? 
A substance resembling a salt, the difference 
COMPOUND ETHERS. CHEMISTRY AND TOXICOLOGY. 
being that the hydrogen of the acid is replaced 
by a hydrocarbon place ot by “a metal. 
The alcohols behave towards the acids iff a man- 
ner precisely like the metallic hydroxids : 
Nh f° + l}° = NK }° + h[° 
Nitric 
acid. 
Potassium 
hydroxid. 
Potassium 
nitrate. 
Water. 
+ «™|o = c™:jo+HJo 
Nitric 
acid. 
Alcohol. 
Ethyl nitrate or 
nitric ether. 
Water. 
See Q. 715. 
758. What is the formula of nitrous ether, and 
in what officinal vrevaration does it SIHil * 
®P*r^tus *theris nitrosi, U. S. 
Br. Sweet spirits of nitre is a solution of this 
substance in alcohol. 
759. What is the composition of the true sul- 
furic ether ? 
S°a|0 _ 
(CaH6)3 f ~ 
ethyl sulfate. 
760. Name some of the compound ethers used in 
medicine, and give their formulae. 
Ethyl acetate = JEther aceticus, U. S. ; 
Amyl nitrite = amyl nitris, U. S. ; 
(CfH°i) | O. Spermaceti = cetaceum, U. S., 
Br., consists essentially of cetyl palmitate, 
ClrHn° \ °- 
13 194 
ESSENTIALS OF 
761. What are aldehydes ? 
They are substances produced from alcohols 
by a degree of oxidation limited to the removal 
of hydrogen, without introduction of oxygen. 
The name is a corruption of alcoholum' dehydfo- 
genatum. 
762. Explain by graphic formula, the relations 
of the aldehydes to the alcohols and acids. 
ALDEHYDES. 
ch3oh 
CHs 
COH 
I 
ch3 
COOH 
I 
CHS 
Ethyl 
alcohol. 
Acetic 
aldehyde. 
Acetic 
acid. 
It appears from these formulae that the alde- 
hydes are intermediate between the alcohols and 
the acids, into the former of which they are 
readily converted by the introduction of Ha, and 
into the latter by oxidation. 
763. Describe the properties of acetic alde- 
hyde. 
It is a colorless, mobile liquid, having a strong, 
suffocating odor ; boils at 21° (69°.8 F.); soluble 
in all proportions in water, alcohol, and ether. 
Taken internally it produces rapid and deep in- 
toxication. It is readily convertecTinto a poly- 
mere, paraldehyde, C6Hi203, a substance liquid 
above 10°.5 (50°.9 F.), but crystalline below that 
temperature. 
764. Explain the relation between chloral and 
aldehyde. 
Chloral is aldehyde in which _II3 has been CHEMISTRY AND TOXICOLOGY. 
195 
replaced by Cl3, therefore trichloraldehyde 
COH 
CC13. 
765. Describe the properties of chloral. 
A colorless, oily liquid, having a penetrating 
odor and an acrid, caustic taste; sp.gr. 1.5; 
boils at 94°.4 (201°.9 F.) ; very soluble in water, 
alcohol, and ether. With a small quantity of 
water, chloral combines to form a crystalline 
hydrate, CC]3C0H,H20. 
766. What reaction takes place between chloral 
or its hydrate and the alkalies ? 
When the two are brought together the mix- 
ture becomes milky, and after a time separates 
into two layers, the lower of chloroform, and the 
upper a solution of an alkaline formate : 
CsHCLO 4 KIIO = CHCL + CH02K 
Chloral. 
Potassium 
hydroxid. 
Chloroform. 
Potassium 
formate. 
767. Describe the prominent symptoms of acute 
chloral poisoning. 
Deep sleep, with the vessels of the head and 
neck greatly congested, accelerated pulse, widely 
dilated pupils, and deep though irregular respira- 
tion. Later the face becomes blanched and livid, 
the pupils contracted, the circulation and respira- 
tion fail, and the temperature falls. In some cases 
death occurs in from one-quarter to one hour in a 
condition of collapse. The usual fatal period is 
8-10 hours. 
768. What treatment is indicated in acute 
chloral poisoning f 196 
ESSENTIALS OF 
Stomach pump. Artificial respiration, flagel- 
lation, faradism (strychnin cautiously ?). 
(For Acetals, Ketones (Acetones), and Ni- 
troparaffins, see Manual, pp. 271-273.) 
AJUINS, MONAMINS (AMIDOPARAFFINS), AND 
r MONAHIDS. 
769. What are amins and amids ? 
Substances derivableTTBfn ammonia by substi- 
tution of hydrocarbon, or of oxidized TadTeatS'Tor 
a portion or all of the hydrogen. If the substi- 
tuted radicals be hydrocarbon, the substance is 
an amin; if oxidized, an amid. 
CH3) 
h In 
H 
C2H30 ) 
h In 
H 
Methylamin. 
Acetamid. 
If the substitution occur in a single molecule 
of ammonia, and the radical or radicals be uni- 
valent, the substance is a monamin or monamid. 
If it contain a single substituted radical, it is a 
primary monamin or monamid ; if two, second- 
ary ; and if three, tertiary: 
CHa) 
h In 
H 
CH3 ) 
ch3 [n 
H i 
C2H30 ) 
C2H30 [■ N 
C2H30 ) 
Primary 
monamin; 
Methylamin. 
Secondary 
monamin ; 
Dimethylamin. 
Tertiary 
monamid; 
Triacetamid. 
The amins are also known as compound ammo- 
nias, as they are substances capable of behaving CHEMISTRY AND TOXICOLOGY. 
197 
toward acids, in the same way as ammonia, to 
form hydroxid s and salts : 
ii4n, oh 
Ammonium hydroxid. 
(CH3)4N, OH 
Tetramethylammonium 
hydroxid. 
H4N, Cl 
Ammonium chlorid. 
(CH3)4N, Cl 
Tetramethylammonium 
chlorid. 
770. Where does trimetliylamin exist in nature ? 
It occurs, associated with monomethylamin and 
dimethylamin, in cod-liver oil, guano, in many 
vegetable substances, in herring pickle. It is 
produced, along with several other amins, in 
putrefaction of fish, starch paste, brain tissue, 
muscular tissue, and albuminoid substances, and 
exists, accompanied by more active alkaloids, in 
blood serum, etc., which have served for the cul- 
ture of various bacteria. 
771. Describe the pi'operties of trimethylamin. 
An oily liquid, having a disagreeable odor of 
fish ; boils at 8° (48°.2 F.); alkaline, soluble in 
H»0, alcohol, and ether. It combines with acids 
to form crystallizable salts. 
772. Where does cholin exist in nature, and how 
is it produced ? 
It occurs in hops, fungi, certain seeds, human 
placenta, bile, and yolks of eggs. It is produced 
by the decomposition of lecithin (see Q. 915) and 
during the first 24-48 hours of putrefaction of 
animal tissues. 
773. Describe the properties of cholin. 
A thick syrup, soluble in H20 and in alcohol; 198 
ESSENTIALS OP 
strongly alkaline in reaction ; is a strong base, 
forming crystalline salts. When heated it splits 
up into glycocol (q. v.) and trimethylamin. It is 
poisonous only in large doses. It is isomeric, but 
not identical with neurin. (See below, and Man- 
ual, pp. 276, 277.) 
774. What vegetable alkaloids are monamins? 
Amanitin and muscarin, both existing in poi- 
sonous fungi. The latter is also a product of pu- 
trefaction. Both are poisonous. 
775. What other monamins are produced during 
putrefaction ? 
Neurin, a substance isomeric with cholin, but 
more actively poisonous. 
(For Monamids see Manual, pp. 278, 279.) 
AMIDO ACIDS, 
776. What are amido acids ? 
They are substances, partly acid and partly ba- 
sic in function, produced from the acids by the 
substitution of the group (NH2) for an atom of H 
in the radical. Thus : 
CH, 
COOH 
CH2(NH2)' 
COOH 
777. Under what other names is amidoacetic 
add known ? 
Acetic acid. 
Amidoacetic acid. 
Glycin, glycocol, glycocin, gelatin sugar. 
778. How does it occur in the body ? 
It is not found in tlie economy as such, but CHEMISTRY AND TOXICOLOGY. 
199 
enters into the composition of a peculiar acid, 
which is found as its sodium salt in the bile, and 
is known as glycocliolic acid. 
779. What other peculiar acid is found in hu- 
man bile ? 
Taurocholic acid ; also in the form of its so- 
dium salts. 
780. Describe the Pettenkofer test for the biliary 
acids. 
Add to the pure aqueous solution of the acids, 
or of their salts, one or two drops of a so- 
lution of cane sugar (1-4) ; agitate ; float this 
liquid carefully upon concentrated H2S04; a tur- 
bid zone is formed at the junction of the two lay- 
ers, soon replaced by a deep purple zone which 
gradually extends upward and downward. 
781. To what substance is this reaction due t 
Cholic acid, formed by the decomposition of 
the taurocholate or glycocholate. 
782. Why is Pettenkofer’s reaction not avail- 
able for the clinical detection of biliary salts in the 
urine f 
As the same appearances are produced, under 
the same conditions, by many other substances, 
the test is only reliable when applied to a simple 
aqueous solution of the biliary salts. The prepa- 
ration of such a solution from the urine can only 
be accomplished by an elaborate process. No re- 
liance is to be placed upon indications obtained 
by application of the test directly to the urine. 
783. Under what other name is amidocaproic 
acid known, and what is its constitution ? 
Leucin. 
C8H10(NH2)O |0 200 
ESSENTIALS OF 
784. Where does it occur, and hoic is it formed f 
It exists in most glandular organs. It has not 
been detected in the blood or urine in health, but 
appears in the latter fluid in yellow atrophy of 
the liver. It results from the decomposition of 
albuminoid substances by the action of strong 
alkalies or acids, and during putrefaction. In 
the body it is formed during the processes of nu- 
trition, and is subjected to further change. It is 
not eliminated in health. 
(For a more complete account of these sub- 
stances and of the Betains, Amidins, Aldehy- 
dins, and Hydrazins, see Manual, pp. 280-291.) 
AZOPARAFFINS, NITRILS, CYANOGEN COMPOUNDS. 
785. What does the syllable azo indicate ? 
That the substances are derivatives obtained 
from the hydrocarbons by the substitution of an 
atom or atoms of nitrogen. Thus hydrocyanic 
acid, CNH, may be considered as methane, CH4, 
in which Hs is replaced by N. Azobenzene con- 
sists of two molecules of benzene, C«He, united, 
with loss of two atoms of hydrogen, by two 
atoms of nitrogen, C6H5 — N = N — Celle. 
786. What does the syllable nitro indicate ? 
That the substance contains the substituted 
group (NvOa)'. Thus nitrobenzene is derived 
from benzene, C6H6, by substitution of (NOs)' 
for H : C.H..NO,. 
787. W hat does the syllable amido indicate ? 
That the substance contains the substituted 
group Thus amidoacetic acid (gly- 
cocol, see Q. 778) is derived from acetic acid, CHEMISTRY AND TOXICOLOGY. 
201 
CH3,COOH, by substitution of NH2 for H : CH2- 
(NH2).COOH. 
788. What is the composition and valence of 
the radical cyanogen ? 
(CN). Univalent. 
789. Give the formula, proper name, and proper- 
ties of cyanogen gas. 
CN ) 
Qjq- >• = (CN)a. Dicyanogen. At ordinary 
temperatures a colorless gas, having a penetrat- 
ing odor of bitter almonds ; very irritating to the 
eyes and air passages ; very poisonous ; soluble 
in water, alcohol, or ether. 
790. Give the formula and synonyms of hydro- 
gen cyanid. 
CN ) 
j-. Hydrocyanic or prussic acid ; azo- 
methane (see Q. 782, and nitrils Q. 803). 
791. What is the strength of Acid. Hydrocyan, 
mi., U. 8. P. f 
Two per cent, of anhydrous acid. 
792. What are its characters ? 
A colorless liquid, having an odor of bitter 
almonds and a bitter taste; very prone to de- 
composition, especially when exposed to light. 
Highly poisonous. 
793. What other substances contain hydrocyanic 
acid ? 
Oil of bitter almonds ; bitter-almond water ; 
cherry-laurel water ; wild-cherry bark, and the 
kernels of the peach, plum, etc. 
794. Explain the formation of hydrocyanic acid 
in oil of bitter almonds. 
It does not pre-exist in the almonds, but is 202 
ESSENTIALS OF 
formed by the reaction of two substances, known 
as amygdalin and emulsin (the former does not 
exist in sweet almonds). This reaction takes 
place in the preparation of the oil, or, when bit- 
ter almonds are eaten, in the mouth and stomach. 
795. Explain the constitution of the cyanids. 
Hydrogen cyanid is an acid, and behaves in a 
manner similar to hydrochloric acid : 
HC1 + KHO = KC1 + II20 
Hydro- 
chloric 
acid. 
Potassium 
hydroxid. 
Potassium 
chlorid. 
Water, 
H{CN) + KHO = K(CN) + H20 
Hydro- 
cyanic 
acid. 
Potassium 
hydroxid. 
Potassium 
cyanid. 
Water. 
796. State the properties and uses of potassium 
cyanid. 
Hard, dull white, amorphous solid, having an 
odor of hitter almonds, and an alkaline taste ; 
very soluble in water, sparingly in alcohol. It 
is decomposed by even the weak acids, with lib- 
eration of hydrocyanic acid, and is consequently 
very poisonous. It is used largely in photogra- 
phy and in electro-plating. 
797. How is silver cyanid prepared, and what 
are its characters ? 
By passing hydrocyanic acid through a solu- 
tion of silver nitrate to saturation, and washing 
the precipitate. A tasteless, white powder ; in- 
soluble in water, but soluble in solution of potas- 
sium cyanid. 
798. Explain its use in pharmacy. 
To prepare extemporaneously a solution of by- CHEMISTRY AND TOXICOLOGY. 
203 
drocyanic acid of known strength. Take 8.3 
grams pure HC1, of sp. gr. 1.16, and dilute with 
water to make 98 c.c.; add to this 9.925 grams 
silver cyanid ; the resulting fluid, separated from 
the silver chlorid by filtration, contains 2 per 
cent. HCN. [The materials must be pure, and 
the weighings accurate.] 
799. Describe the tests for hydrocyanic acid or a 
cyanid. 
1. With AgN03 a white precipitate, soluble in 
solutions of the cyanids or of the thiosulfates. 2. 
Add NH4HS; evaporate to dryness ; add Fe2Cl6 
solution: a red color. 3. Add KHO solution 
and then solution of FeS04 containing (Fe2)- 
(S04)3 ; a green precipitate, which forms a blue 
solution with HC1. 4. Moisten filter paper with 
freshly prepared tincture of guaiac, dip the paper 
into very dilute solution of CuS04, and, after 
drying, moisten with the solution to be tested : a 
deep blue color. 
800. Describe the symptoms of. hydrocyanic acid 
poisoning. 
Its action is always rapid Relatively small 
doses cause an immediate sense of constriction of 
the throat, followed in one to two minutes by 
sense of pressure in the head, vertigo, confusion 
of intellect, and loss of muscular power. The 
pulse is quick, the respiration slow and stertorous. 
Tetanic convulsions and involuntary discharges 
of urine and faeces occur, followed by paralysis. 
Death follows, in from two hours to two days, 
from asphyxia. When large doses are taken no 
subjective symptoms are observed. The patient 
loses consciousness in less than one minute. 204 
ESSENTIALS OF 
There is a short convulsive seizure, usually ac- 
companied by evacuations of faeces, after which 
the patient lies perfectly still, with no sign of life, 
save an almost imperceptible pulse and infrequent 
spasmodic respiratory efforts, in which inspira- 
tion is short and expiration protracted. Death 
follows in from five to twenty minutes. 
801. What treatment should be followed in poi- 
soning by hydrocyanic acid ? 
There is no time for administration of anti- 
dotes. The patient should be stripped, and cold 
water dashed upon the head and spine, which 
are then rubbed dry with warm towels, and the 
cold douche repeated, after which artificial respi- 
ration should be practised. Inhalations of chlorin 
or ammonia, largely diluted with air, are recom- 
mended. 
802. What substances other than hydrocyanic 
acid cause cyanic poisoning ? 
Potassium cyanid, mercuric cyanid, bitter al- 
monds in sufficient quantity, oil of bitter almonds, 
and cherry laurel water. 
803. What are the nitrils ? 
The hydrocyanic ethers of the monoatomic al- 
coholic radicals. Thus: CHs,CNis methyl cyan- 
id, or acetonitril. Hydrocyanic acid itself may 
be considered as formonitril, HCN. (See Man- 
ual, pp. 293, 294.) 
804. Describe the constitution of cyanic acid and 
the relation of its ammonium salt to urea. 
The empirical formula is CNOH, correspond- 
ing to which are two isomeric compounds: the 
normal, N^C—OH, and the iso, 0=C=N—H. 
Ammonium isocyanate, 0=C=N—NH4, is con- CHEMISTRY AND TOXICOLOGY. 
205 
verted by heat into urea, which has the same 
empirical formula, CONaH4, but differs in con- 
stitution, having the graphic formula HaN—CO 
—NHS. 
805. What compound containing sulfur cor- 
responds to cyanic acid, and of what physiological 
and analytical interest is it ? 
Thiocyanic acid, NCSH. It exists in the saliva 
in combination. The free acid is actively poi- 
sonous. Its ammonium or potassium salt is used 
as a test for the ferric compounds, with which it 
gives a deep red color, discharged by HgCla. 
806. What are the metallocyanids? 
Compounds of cyanogen with certain metals, 
which form salts, in which the analytical charac- 
ters of the metals are completely masked. The 
best known are those containing iron, as potas- 
sium ferrocyanid, K4[(CN)'6Fe//]IV, - yellow 
prussiate of potash ; potassium ferricyanid, K6- 
[(CN)i2(Fe2)VI]VI, = red prussiate of potash ; fer- 
ric ferrocyanid, or Prussian blue ; ferrous ferri- 
cyanid, or Turnbull’s blue. There are also 
cobalticyanids, platinocyanids, argentocyanids, 
etc. 
(For IIydroxy.lamin Derivatives and Sul- 
fur Derivatives, etc., see Manual, pp. 296-300.) 
ACRYLIC SERIES OF ACIDS. 
807. IIow do acids of this series differ from those 
of the acetic series in composition ? 
They contain two atoms of hydrogen less, their 
general formula being CnH2n-202. 206 
ESSENTIALS OF 
808. What two acids of this series are of medical 
interest ? 
Crotonic acid, CJIcOa, and oleic acid, Ci8- 
HS4Oa. 
809. Mention the points of interest of crotonic 
acid. 
It exists, in combination with glycerol, as an 
ether in croton oil. The aldehyde corresponding 
to this acid, C4H80, furnishes a chlorinated de- 
rivative similar to chloral, a hydrate of which is 
used medicinally under the name croton chloral 
hydrate. 
810. In what form does oleic acid exist in na- 
ture ? 
In combination with glycerol it forms the 
greater part of all the oils, animal and vegetable. 
811. What are its properties ? 
A colorless or slightly yellow, oily fluid, neu- 
tral in reaction when pure. Upon exposure to 
air it becomes yellow, rancid, and acid. At 14° 
(57°.2 F.) it solidifies to a crystalline mass. Al- 
most insoluble in water, soluble in alcohol and 
ether. 
812. In what officinal preparation is allyl thio- 
cyanate contained, and what are the properties of 
that substance ? 
In the essential oil of mustard = Oleum sina- 
pis volatile, U. S. The thiocyanate, to which 
the rubefacient and vesicant actions of mustard 
are due, is produced by the action of a nitrogen- 
ized substance, called myrosin, upon potassium 
myronate, contained in the mustard, in the pre- 
sence of H20 at a moderate temperature. Myro- 
sin is coagulated and rendered inert by a tern- CHEMISTRY AND TOXICOLOGY. 
207 
perature of 40° (104° F.), or by contact with 
acetic acid. 
(For other Allylic Compounds see Manual, 
pp. 301-307.) 
HYDROCARBONS. CnIIm. 
818. Which is the most important member of 
the second series of hydrocarbons ? 
Ethylene, CaH4; also known as olefiant gas, 
elayl, or heavy carburetted hydrogen. 
814. Of what industrial product is it the most 
important constituent ? 
Illuminating gas. 
814a. State its properties. 
It is a colorless gas, having a peculiar, dis- 
agreeable odor ; it burns with a luminous flame, 
and forms explosive mixtures with air and oxy- 
gen. It is irrespirable. Equal volumes of this 
gas and chlorin unite directly to form an oily 
liquid having the composition CaH4Cla, known 
as “ Dutch liquid.” 
8145. What series of alcohols correspond to these 
hydrocarbons ? Explain their constitution. 
The glycols. The primary alcohols of the 
ethylic series are monoatomic (see Q. 716, 717), 
and contain a single group CHaOH. The gly- 
cols are diatomic and contain two such groups : 
CIIaOH 
I 
CH3 
CHaOII 
CHaOH 
Monoatom ic 
primary alcohol. 
Diatomic 
primary alcohol. 208 
ESSENTIALS OF 
ACIDS CnH2n03 AND CnHjn-204. 
815. Explain the relations between the primary 
glycols and the acids derived from them by oxida- 
tion. 
The primary monoatomic alcohols, containing 
a single group CHaOH (see Q. 716, 717, 745), 
yield by oxidation each a single acid : 
CHaOH 
I 
CH, 
COOH 
CH3 
Ethylic alcohol. 
Acetic acid, 
The glycols, containing two groups CH2OH, 
produce two series of acids by oxidation, each of 
which is diatomic, as the alcohol is diatomic, but 
one is monobasic, containing a single group 
COOH, while the other is dibasic, containing 
two such groups: 
CHaOH 
I 
CHaOH 
CHaOH 
I 
COOH 
COOH 
I 
COOH 
Diatomic 
alcohol. 
Glycol. 
Diatomic 
monobasic 
acid. 
Glycolic acid. 
Diatomic 
dibasic 
acid. 
Oxalic acid. 
ACIDS. SERIES CnHanOs, 
CnII2n-aO ) 
Ha ) 
816. How does the first term of this series differ 
from the remainder in basicity? 
The first acid of the series is dibasic, while the CHEMISTRY AND TOXICOLOGY. 
209 
remainder are monobasic. The graphic formulae 
indicate the cause of this difference : 
/O—H 
O = C 
\0—H 
O =C—O-H 
H2=i—O—H 
0=C—0—H 
0=C—O—H 
Glycolic acid. 
Monobasic. 
Oxalic acid. 
Dibasic. 
Carbonic acid. 
Dibasic. 
817. Does carbonic acid exist free in nature? 
It does not; the substance usually designated 
by this name is the corresponding anhydrid. 
818. W hat compounds of carbon and oxygen 
exist free? 
Carbon monoxid CO = Carbonic oxid. 
“ dioxidC02 = “ anhydrid. 
819. Tinder what conditions is carbon monoxid 
formed ? 
When coal is burnt with an insufficient supply 
of air; in open charcoal fires; by passing C02 or 
steam over red-hot coal; by heating oxalic acid 
with H2S04. 
820. Describe the prominent properties of CO. 
It is a colorless, odorless, tasteless gas, lighter 
than air, very sparingly soluble in H20. It 
unites readily with O to form C02, burns in air 
with a blue flame, and reduces metallic oxids at 
high temperatures. 
821. What is the action of CO on the animal 
economy ? 
It is actively poisonous. _ It causes death by 
forming a compound witli haemoglobin which 
is more stable than the oxygen compound, and 
whose formation consequently interferes with 
14 210 
ESSENTIALS OF 
the oxygen-carrying function of the blood pig- 
ment. 
822. What industrial gases contain GO ? 
The gases discharged from blast furnaces and 
from copper furnaces (18 to 32$); the gases ema- 
nating from charcoal fires; the gases produced 
during the combustion of anthracite coal with 
deficient draught; coal gas (4 to 7.5$); “water- 
gas ” (30 to 35$). 
823. What treatment should be followed in as- 
phyxia by CO, and what is the prognosis ? 
Stimulants and plenty of fresh air may prevent 
cessation of respiration, but it is questionable 
whether they or artificial respiration are of much 
value after the breathing has stopped. The 
prognosis is very unfavorable. 
824. What is the appearance of the blood after 
death from CO? 
It is persistently bright-red in color. When 
examined spectroscopically, it shows two absorp- 
tion bands of equal intensity, and nearer to the 
violet end of the spectrum than those of oxy- 
hsemoglobin. A solution of NaHO (sp. gr. 1.3) 
added to normal blood produces a black precipi- 
tate, which is greenish-brown in thin layers. 
With carbon monoxid blood, the same reagent 
forms a bright-red clot. 
825. Under what names is COt known ? 
Carbon dioxid, carbonic anhydrid, and, im- 
properly, carbonic acid. 
826. IIow is COi produced ? 
By the combustion or complete oxidation of 
carbon or of any substance containing carbon; by 
the decomposition of a carbonate by a stronger CHEMISTRY AND TOXICOLOGY. 
211 
acid; by the respiration of animals; by fermenta- 
tion. Carbon dioxid is also discharged into the 
atmosphere by volcanoes, or fissures in the earth 
in volcanic regions; from mineral springs; from 
lime kilns, cement works, etc.; and from mines 
by explosions of fire damp. 
827. Give the principal physical properties ofCOt. 
Under ordinary conditions of pressure and tem- 
perature, a colorless, odorless gas, having a faint 
acid taste; under the influence of increased pres- 
sure and diminished temperature, it forms a liq- 
uid which is very volatile, and which solidifies 
at —90° ( —130° F.). Gaseous C02 will neither 
burn nor support combustion. It is soluble in 
water, the quantity dissolved increasing with the 
pressure. 
828. In what proportion does CO4 exist in air ? 
About 4 in 10,000. 
(See Manual, pp. 319-326.) 
829. W(iy does it not accumulate in the air? 
Because it is absorbed by plants under the in- 
fluence of sunlight, and is by them decomposed, 
the carbon entering into the various organic sub- 
stances produced by the plant. 
830. What action has pure GOa when inhaled? 
It produces spasm of the glottis and almost 
immediate death. 
831. In what two ways may the pu'oportion of 
GOi in air be increased ? 
1. By the addition of C02 to normal air, as in 
the processes of fermentation and lime burning. 
2. By the oxidation in air of a substance contain- 
ing carbon, as in the processes of combustion 
and respiration. 212 
ESSENTIALS OF 
832. W hich of these most rapidly renders air un- 
fit for respiration, and why? 
The second ; because not only is the deleteri- 
ous gas increased, but it is formed at the expense 
of the oxygen, which is correspondingly dimin- 
ished. 
833. How does air coming from the lungs differ 
from inspired air ? 
The proportion of O is diminished, while that 
of C02 and H20 is increased. 
834. What proportion of COi is contained in 
expired air? 
About 4 per cent, in volume. 
835. W hat proportion of oxygen is absorbed from 
the air in passing through the lungs ? 
About 5 per cent, in volume. 
836. How do candles and gas lights compare with 
human beings in the quantity of oxygen which they 
consume, and of carbon dioxid which they produce ? 
A candle about equals an adult man in the quan- 
tity of O consumed, and of C02 produced in its 
combustion. An ordinary gas-burner is equal to 
ten adults. 
j. 837. What is “ soda water ” ? 
Water holding in solution a large quantity of 
C02 under pressure. The gas escapes in bubbles 
when the pressure is removed. 
838. How is carbon dioxid obtained? 
By decomposing a carbonate by an acid : 
Na2C03 + 2HC1 = 2NaCl + H20 + C02 
Disodic 
carbonate. 
Hydrochloric 
acid. 
Sodium 
chlorid. 
Water. 
Carbon 
dioxid. 
839. By what tests is it recognized ? 
By the formation of a white precipitate when CHEMISTRY AND TOXICOLOGY. 
213 
it is bubbled through lime water. By being ab- 
sorbed when confined over a solution of potas- 
sium hydroxid. 
840. Explain the constitution of the carbonates. 
(COY' ) 
Although free carbonic acid, 1 >• 03, does 
not exist, the corresponding salts are widely dif- 
fused in nature. As the acid is dibasic, the uni- 
valent metals form with it two series of salts, in 
one of which only one atom of hydrogen is re- 
placed by a metal, and in the other both: 
,0Na' 
0 =C( 
x0II 
,ONa' 
0= C( 
x0Na' 
With bivalent metals, two salts also exist, each 
containing a single atom of the metal, in the one 
case substituted in a single molecule of the acid, 
in the other in a double molecule, 
841. What compound of carbon and sulfur re- 
sembles carbon dioxid in its constitution ? 
Carbon disullid, CS2, or thiocarbonic anhy- 
drid. 
842. What are its properties ? 
Clear, colorless liquid, refracting light 
strongly, having a disagreeable, penetrating odor 
and sharp taste ; heavier than H20, with which 
it does not mix ; volatile at ordinary tempera- 
tures, boils at 42° (107°.6 F.); has not been so- 
lidified ; burns readily, forms an explosive mix- 
ture with air ; good solvent for fats, resins, and 
india-rubber. 
848. How is ordinary ‘ ‘ lactic acid ” formed, 
and under what other names is it known? 
By a peculiar fermentation, known as the J^r,- 214 
ESSENTIALS OF 
tic, of sugars, in sour milk, and in a variety of 
other fermented products, as in sauerkraut and 
some kinds of pickles. It also exists in the stom- 
ach during digestion of vegetable food, but is not 
a constituent of the gastric secretion. It is also 
called lactic acid of fermentation: Acidum lacti- 
cum, U. S. 
844. State its characters. 
It is a clear, syrupy liquid, having a slight, 
not unpleasant odor and a sour taste ; it is heav- 
ier than HjO, with which it mixes in all propor- 
tions, as well as with C2H,0 and C4Hi0O. It is 
a strong monobasic acid, although it contains 
two extraradical atoms of hydrogen. 
845. Where does sarcolactic acid occur? 
In the juices of muscular tissue, bile, and in 
the urine of phosphorus poisoning. 
ACIDS. SERIES C11H211-2O4. 
CnH2n-.tOa ) q 
H2 ) 3 
846. State the basicity of the acids of the series 
CxiIIm-iOi, and explain their relation to the 
series CixILmO-i and to the glycols. 
They are dibasic. They are the products of 
oxidation of the glycols, more complete than in 
the case of the series CnH2nOs: 
CHaOH 
I 
CHaOH 
CH2OH 
I 
COOH 
COOH 
COOII 
Glycol. 
Glycolic acid. 
Oxalic ficid- CHEMISTRY AND TOXICOLOGY. 
215 
847. What is the composition of oxalic acid,and 
how does it occur in nature ? 
It exists, in combination 
with K, Na, and Ca, in many vegetables, to 
which it gives a sour taste : sorrel, pie-plant, 
etc. 
848. IIow is it prepared, industrially ? 
By the oxidation of starch, sugar, wood, or 
other organic matter, by KHO, or by HNOs. 
849. Describe its properties. 
Crystallizes in colorless, odorless prisms, with 
2Aq ; has a sour taste ; soluble in 8 parts cold, 
and much more soluble in hot water, as well as 
in alcohol and ether. It is a strong dibasic acid ; 
its solutions have a strong acid reaction and act 
as corrosives upon animal tissues. Poisonous. 
850. In mistake for what substance is oxalic acid 
sometimes taken? 
Epsom salt. 
851. Describe the symptoms of oxalic acid poi- 
soning. 
They vary much in character, according to the 
amount and degree of concentration of the dose. 
With large doses in concentrated solution, the 
corrosive action of the acid is the more promi- 
nent ; with smaller amounts its truly poisonous 
effects are more apparent. 
The sour taste of the acid is rapidly followed 
by a burning pain, increasing in intensity, in the 
mouth, throat, and stomach ; and persistent 
vomiting of a dark, “coffee-ground” material. 
The pulse becomes small and imperceptible, and 
COOH ) 
[• =C204H3. 
COOH J 216 
ESSENTIALS OF 
the patient dies in collapse, preceded frequently 
by convulsions, within half an hour. 
If the case be prolonged, swallowing becomes 
very difficult and painful ; there are numbness 
and tingling of the skin; twitchings of the 
facial muscles ; convulsions, frequently tetanic ; 
delirium ; and lumbar pain. 
Death occurs in some cases within three to ten 
minutes, sometimes almost immediately, and in 
some cases it is delayed for several days. 
852. W hat treatment should be followed in cases 
of oxalic acid poison ing ? 
Magnesia (magnesia usta), or slaked lime sus- 
pended in a small quantity of water, or muci- 
laginous liquid, should he given as soon as pos- 
sible. If vomiting do not occur, and if the 
symptoms of corrosion be not marked, an emetic. 
The stomach pump should not be used, nor 
should the alkaline carbonates be depended upon 
as antidotes. 
853. W hat action has oxalic acid upon cloth and 
writing ink ? 
It forms a brown stain upon cloth, and bleaches 
writing ink. Writing removed by oxalic acid 
may be restored in blue by moistening with so- 
lution of potassium ferrocyanid. 
854. Give tests for oxalic acid and the soluble 
oxalates. 
Calcium chlorid added to the solution, neu- 
tralized with NH4HO, forms a white, crystalline 
precipitate, which is insoluble in acetic acid, but 
soluble in HC1. The same precipitate is formed 
with lime water, or solution of calcium sulfate. 
Silver nitrate, in neutral solution, forms a white CHEMISTRY AND TOXICOLOGY. 
217 
precipitate, which is easily soluble in HN03. 
This precipitate does not darken when the fluid 
is boiled, but when dried and heated it explodes. 
855. Explain the constitution of the oxalates. 
COOH 
Oxalic acid being dibasic, | , forms with 
COOH 
COOM' 
the univalent metals two series of salts, | 
COOH 
COOM' 
and | , and with the bivalent metals a sin- 
COOM' 
COO 
gle series, 1 ,R'\ 
COO' 
(For other Acids, Compound Ethers, Alde- 
hydes, and Anhydrids of this series, see Man- 
ual, pp. 329-332.) 
DIAMINS AND TRIAMINS. 
856. Explain the constitution of the diamins 
and triamins. 
As the monamins (see Q. 769) are produced by 
the substitution of univalent hydrocarbon radi- 
cals in a single molecule of ammonia, so the di- 
amins are formed by the substitution of bivalent 
hydrocarbon radicals in two molecules of am- 
monia, e.g., methylendiamin, H2N—CH2—NHS; 
and the triamins by the substitution of trivalent 
radicals in three molecules. Like the monamins, 
they are capable of forming salts and liydroxids 
corresponding to those of ammonium, 218 
ESSENTIALS OP 
857. W hat is a ptomai'n ? 
An alkaloid (see Q. 1028) produced during the 
putrefaction of animal substances. 
858. What ptomains are known to be diamins ? 
Putrescin=tetramethylendiamin, H 2N—(CH 2)4 
—NH2; and Cadaverin=pentamethylendiamin, 
HjN—(CH2)6—NH2. Trimetliylendiamin and 
Hexamethylendiamin are also ptomains. Neu- 
ridin, C6Hi4N2, and Saprin, CbHi,N2, are also 
diamins of undetermined constitution. 
859. Describe the prominent properties of putres- 
cin and cadaverin. 
The free bases are syrupy, colorless liquids, the 
former having a seminal odor, and the latter a 
strong, disagreeable odor resembling that of 
conii'n. They absorb C02 from the air, and form 
crystalline salts with acids. They are produced 
during the later stages of putrefaction, and are 
not actively poisonous. 
860. IT hat is a leucomain ? 
An alkaloidal or basic substance normally pro- 
duced in the animal body during life, or ob- 
tained from it. 
861. What leucomains are known to be triamins 
or derivatives of triamins ? 
Guanidin ; Methylguanidin ; Creatin ; Crea- 
tinin ; several other bodies closely related to 
creatinin. 
862. Describe the constitution and relations of 
guanidin and methylguanidin. 
Guanidin, first obtained from the oxidation of 
guanin, is carbotriamin (formula I. below). 
Methylguanidin (formula II. below) is formed 
by the oxidation of creatin and creatinin, which CHEMISTRY AND TOXICOLOGY. 
219 
are closely related in constitution, and is also a 
product of putrefaction. Both are crystalline 
solids which combine with acids to form salts: 
,NHa 
HN=C( 
xNHa 
/NHj 
HN=C( 
XNH(CH,) 
I. Guanidin. 
II. Methylguanidin. 
863. Describe the occurrence and properties of 
creatin and creatinin. 
Creatin exists in muscular tissue. It is a crys- 
talline solid, soluble in boiling H20 and in alco- 
hol, which is readily converted into creatinin, 
which differs from it by II20 less. Creatinin is a 
constant constituent of the urine, being eliminated 
in the daily quantity of 0.6 to 1.3 gram (9.25 
to 20 grains. It is a crystalline solid, soluble in 
water, a strong base, alkaline in reaction, and 
forms a very sparingly soluble, crystalline, double 
salt with zinc chlorid. 
DIAMIDS. IMIDS. CARBAMIC ACIDS. 
864. Explain the constitution of the diamids 
and of the imids. 
The diamids are substances derived from a 
double molecule of ammonia by the substitution 
of one or more bivalent oxidized radicals for one 
or more pairs of hydrogen atoms. The imids are 
derived from a single molecule of ammonia by 
the substitution of a bivalent, oxidized radical 
for two of its hydrogen atoms; 220 
ESSENTIALS OF 
Ha ) 
Ha > Na 
Ha; 
(CO)") 
Ha [Na 
Ha; 
H) 
HVN 
H ) 
ro, 
HfN 
Ammonia; 
double 
molecule. 
Carbamid; 
diamid. 
Ammonia; 
single 
molecule. 
Carbimid ; 
irnid. 
865. Under what names is the amid of carbonic 
acid known, and what is its constitution ? 
Carbamid, Urea. H3N—CO—NHa. 
866. Give the principal physical properties of 
urea. 
Crystallizes in transparent needles or four- 
sided prisms, without Aq ; permanent in air ; 
odorless, having a cooling, slightly bitter taste, 
resembling that of saltpetre. Soluble in an equal 
weight of cold water, very soluble in boiling 
water and in five parts of cold or one part of hot 
alcohol, the solutions being neutral in reaction. 
At 120° (248° F.) it melts, and slightly above 
that temperature is decomposed. 
867. In what animal fluids is urea found? 
In the blood, lymph, humors of the eye, per- 
spiration, and especially in the urine. 
868. What is the source of urea in the economy? 
It is the principal product of the oxidation of 
albuminoid substances in the animal body, and 
is the form in which most of the nitrogen is ex- 
creted. 
869. IIow may urea be obtained synthetically? 
By heating its isomere, ammonium isocyanate. 
(See Q. 804.) 
810. What occurs when an aqueous solution of 
urea is long heated? 
Urea takes up the elements of two piolepules CHEMISTRY AND TOXICOLOGY. 
221 
of water, and is converted into ammonic carbon- 
ate : 
CON2H4 + 2H20 = (NH4)2C03 
Urea. 
Water. 
Diammonic 
carbonate. 
871. Under what other conditions does this 
change occur ? 
Under the influence of certain ferments, and 
of decomposing animal matter. When urea is 
heated with a base or with an acid. When a 
base is used, ammonia is liberated and a carbon- 
ate formed : 
CON2H4 + 2KHO = 2NH, + K2C03 
Urea. 
Potassium 
hydroxid. 
Ammonia. 
Dipotassic 
carbonate. 
When an acid is used, carbon dioxid is given off 
and an ammoniacal salt remains : 
CON2H4 + H2S04 + H20 =(NB4)2S04+ co2 
Urea. 
Sulfuric 
acid. 
Water. 
Diammonic 
sulfate. 
Carbon 
dioxid. 
872. What effect have chlorin, bromin, and ni- 
trous acid upon urea ? 
Chlorin and bromin, and the hypochlorites 
and hypobromites, decompose urea, with forma- 
tion of hydrochloric or hydrobromic acid, carbon 
dioxid, and nitrogen: 
CON2H4 + H20 + 8C]2 = 6HC1 + C02 + N2 
Urea. 
Water. 
Chlorin. 
Hydro- 
chloric 
acid. 
Carbon 
dioxid. 
Nitro- 
gen. 
Nitrous acid (or nitric acid charged with the ox- 
ids of nitrogen) produces an oxidation of urea : 222 
ESSENTIALS OF 
2CON2H4 + 302 = 4H20 + 2C02 + 2N2 
Urea. 
Oxygen. 
Water. 
Carbon 
dioxid. 
Nitrogen. 
873. What occurs when pure nitric or oxalic 
acid is added to a cold concentrated solution of 
urea ? 
The nitrate or oxalate of urea is formed, and, 
as these are much less soluble than urea, they 
separate as crystals. 
874. What quantity of urea is discharged by a 
normal adult in 24 hours ? 
From 25 to 35 grams (about 1 to 3 )• 
875. How does the elimination of urea vary with 
age and sex ? 
Taking the quantity excreted in 24 hours by 
an average adult man at 0 5 grm. for each kilo- 
gram of body weight, it is found that in children 
the elimination is much greater. A child of 6 
years discharges in 24 hours 1 grm. urea for each 
kilo, of body weight. In old persons the elimina- 
tion of urea diminishes. Females discharge less 
urea than males, except during pregnancy, when 
the elimination is much increased. 
876. How does the diet affect the elimination of 
urea ? 
The more highly nitrogenized the diet, the 
greater the elimination of urea. 
877. Give a clinical method for determining 
whether the elimination of urea is excessive or de- 
ficient. 
Take from the fresh, mixed urine of 24 hours 
two samples, one of 5 c c. and the other of double 
that quantity, and place them in watch glasses. 
To the smaller sample add about one-third of its CHEMISTRY AND TOXICOLOGY. 
223 
volume of pure colorless HN03 ; if crystals ap- 
pear in this immediately or within a few mo- 
ments, the amount of urea is above the normal. 
Evaporate the other sample to one-half its bulk 
at a low temperature [over a water-bath, or on 
the corner of a stove, where the temperature 
does not exceed 90° (194° F.)], allow it to cool, 
and add HN03 as before ; if crystals do not form 
within a few moments, the proportion of urea is 
below the normal. 
The quantity of urine passed in 24 hours must 
be taken into consideration ; thus, if, instead of 
the normal quantity of 1,200 c.c., the patient 
only pass 600 c.c., the first sample should be di- 
luted with its own volume of HaO, and the sec- 
ond used without evaporation ; if, on the other 
hand, the urine be that of a diabetic patient 
passing 8,600 c.c. per diem, 15 c.c of the urine 
reduced to 5 by evaporation should be used for 
the first test, and 80 c.c. reduced to 5 for the sec- 
ond. 
(For a more accurate method, see Manual, pp. 
343-345.) 
878. To what 'pathological causes may diminu- 
tion or increase of elimination of urea he due 9 
A diminution may be due to some condition 
interfering with the normal transformation of 
albuminous substances in the body, as in certain 
chronic diseases. More frequently, however, a 
diminished proportion of urea in the urine is not 
due to a diminution in the production, but to the 
fact that the urea formed has not been separated 
by the kidneys, as in uraemia, and in diseases at- 
tended with dropsical effusions. An excess of 224 
ESSENTIALS OF 
urea occurs in fevers and in true diabetes, in 
which it indicates the amount of waste of tissue, 
and is, therefore, a grave symptom. 
COMPOUND UREAS. 
879. What are compound ureas ? 
Substances derived from urea by the substitu- 
tion of radicals for the remaining atoms of hy- 
drogen. Those containing oxidized (or acid) rad- 
icals are called ureids. If derived from a single 
molecule they are monureids ; if from two mole- 
cules of urea, diureids. 
880. Give the formula of uric acid. 
C6H4N4O3. Its constitution has been recently 
established, and shows it to be the diureid of 
tartronic acid. 
881. In what parts of the body does it occur? 
In the urine of the carnivora and in the ex- 
crements of birds, reptiles, and insects ; in the 
blood, spleen, lungs, liver, pancreas, and brain. 
It enters into the composition of many urinary 
calculi, and the so-called “ chalk stones” depos- 
ited in the joints in gout. 
882. In what form does it exist ? 
It does not occur uncombined in the normal 
body, but exists as the urates of sodium and am- 
monium. principally the former. 
883. What is the source of uric acid in the 
economy ? 
It is a product of the oxidation of albuminous 
substances, and is one of the intermediate steps 
in the formation of urea. CHEMISTRY AND TOXICOLOGY. 
225 
884. Give the properties of pure uric acid. 
A light, white powder, composed of small 
crystals ; odorless, tasteless, very sparingly sol- 
uble in HaO, insoluble in alcohol and ether, sol- 
uble without decomposition in Ha904 or HC1. 
Moist uric acid has an acid reaction. It is a 
dibasic acid. 
885. Give a testfoi' the presence of uric acid. 
Moisten with HN03 and evaporate nearly to 
dryness, cool, add NH4HO. If uric acid be pre- 
sent, the HN03 residue is yellow or red, and on 
addition of the NH4HO a brilliant red color is 
produced. 
886. What substance is formed in this reaction ? 
Murexid. 
887. How may uric acid be obtained from 
urine f 
By adding HC1, and allowing the mixture to 
stand. The HC1 unites with the base, and the 
uric acid thus liberated, being insoluble, is depo- 
sited. 
888. How do the crystals obtained by 887 differ 
from those of pure uric acid? 
In being yellow or brown. The coloring mat- 
ter of the urine adheres tenaciously to uric acid, 
and it is very difficult to obtain the pure acid 
from this source. The form of the crystal also 
differs from that of crystals of the pure acid. 
' 889. What is the object of administering lithium 
compounds in diseases attended with excessive pro- 
duction of uric acid ? 
' Urate of lithium is more soluble than urate of 
sodium ; therefore, if the former salt be formed 
in the body in place of the latter, there is less 226 
ESSENTIALS OF 
danger of the formation of deposits. If deposits 
already exist, either in the tissues or as calculi, 
their solution and removal are aided by the for- 
mation of lithium urate. 
890. How much uric acid is normally excreted in 
24 hours? 
From 0.3 to 0.8 gram (4.6 to 12.8 grains). 
891. Give a process for the quantitative determi- 
nation of uric acid in urine. 
Place 200 e.c. of urine in a beaker, add 5 c.c. 
pure HC1; stir, cover, and set aside for 24 hours; 
collect the crystals formed upon a small weighed 
filter, wash with cold distilled water until the 
washings no longer precipitate with silver ni- 
trate ; dry the filter with the adhering crystals, 
and weigh ; the difference between this weight 
and that of the filter gives the amount of uric 
acid. A slight correction is required for the 
sparing solubility of uric acid. If the amount 
of wash water used do not exceed 30 c.c., no 
correction is required ; if it do, add to the result 
0.045 milligr. for each c.c. more than 30 used. 
892. What reaction of the urine favors the 
deposition of uric acid gravel or calculi ? 
A strongly acid reaction. 
893. Where does xanthin occur ? 
In the urine and muscular tissue ; as the main 
constituent of certain rare urinary calculi. 
894. What substance, closely related to xanthin, 
is found in muscular tissue ? 
Hypoxanthin or sarkin. 
895. State the facts of physiological interest con- 
cerning adenin. 
It is a leucomaln separated from extract of CHEMISTRY AND TOXICOLOGY. 
227 
pancreas, being produced along with other com- 
pound ureas by the decomposition of nuclein (see 
Q. 919). It is very widely distributed in the 
vegetable and animal kingdoms, particularly in 
tissues abounding in nucleated cells. It is a 
polymere of hydrocyanic acid, having the for- 
mula C6H6NS. It crystallizes in plates or nee- 
dles, very soluble in hot H20, but sparingly solu- 
ble in cold HaO. It resists oxidizing and hydrat- 
ing agents obstinately. 
895a. What vegetable alkaloids are compound 
ureas, and where do they occur ? 
Theobromin, C7H8N402, occurs in Theobroma 
cacao; and Caffein, C8H,0N4O2, also known as 
thein and guaranin, which exists in coffee, tea, 
Paraguay tea, and in other plants. 
(See Manual, pp. 846-355.) 
TRIATOMIC ALCOHOLS. 
896. W hat important triatomic alcohol is 
known ? Explain its constitution. 
Glycerol; C3H803. A mouoatomic alcohol 
may be regarded as a molecule of water, in which 
one atom of hydrogen is replaced by an univa- 
lent radical: j. O ; a diatomic alcohol as 
a double molecule of water, in which a double 
atom of hydrogen has been replaced by a biva- 
lent radical: ' 2 f- O; and a triatomic al- 
cohol as a triple molecule of water, in which a 228 
ESSENTIALS OF 
triple atom of hydrogen has been replaced by a 
trivalent radical: j. 03 = glycerol. 
The intimate structure of the molecules is 
shown by the graphic formulae : 
ch2oii 
I 
CHS 
ch2oh 
I 
ch2oh 
CH,OH 
I 
CHOH 
I 
CH2OH 
Etbylic alcohol. 
Monoatomic. 
Glycol. 
Diatomic. 
Glycerol. 
Triatomlc. 
897. What does the termination ol indicate ? 
That the substance is an alcohol or a phenol. 
(See Q. 715, 978.) 
898. Give the physical characters of glycerol. 
A colorless, odorless, syrupy liquid; neutral 
in reaction; miscible in all proportions with 
water; having a sweetish taste; not altered by 
exposure to air. 
899. Write the graphic formula of glycerol and 
those of the acids obtainable from it by oxidation. 
CH2OH 
I 
CIIOH 
CII2OH 
CH2OH 
I 
CHOH 
I 
COOH 
COOH 
I 
CIIOH 
I 
COOH 
Glycerol. 
Glyceric acid. 
Tartronic acid. 
900. Where does malic acid occur in nature ? 
It occurs, either free or in combination with K, CHEMISTRY AND TOXICOLOGY. 
229 
Na, Ca, or Mg, in many fruits, such ak apples, 
cherries, the berries of the mountain ash, etc. 
901. Into what salts are the malates, citrates, 
and tartrates converted in the economy, and with 
what influence upon the urine ? 
They are oxidized, with formation of the cor- 
responding carbonates. As these salts are alka- 
line in reaction, they diminish the acidity of the 
urine or render it alkaline. 
902. What are the glycerids ? 
They are compound ethers produced by the 
action between glycerol and the acids. As gly- 
cerol is triatomic, it behaves like the hydroxid of 
a trivalent metal and consequently forms three 
ethers with the monobasic acids : 
gfo + = ( + 
Potassium 
.hydroxid. 
Base. 
Acetic acid. 
Acid. 
Potassium 
acetate. 
Salt. 
Water. 
C^f0+'C.H.O,|0=(C:H,OH0+H}o 
Ethyl hydroxid. 
Alcohol. 
Acetic acid. 
Acid. 
Ethyl acetate. 
Ether. 
Water. 
(CS%3>° + 3(^ = 
Glycerol. 
Alcohol. 
Acetic acid. 
Acid. 
_ (C2H30)3 ) q 
“ (C.H.)"' f 3 
SH}° 
Water. 
Triacetin. 
Ether. 230 
ESSENTIALS OF 
Similarly we have diacetin 
HO, and monacetin, (X^HnOaXCaHeXHO)^ 
903. What imported vegetable and animal sub- 
stances consist of glycerids ? 
The fixed oils and fats. 
904. What is the chemical difference between the 
fixed and volatile oils ? 
The fixed oils are glycerids, constituted as al- 
ready described and capable of saponification. 
The volatile oils are for the most part hydrocar- 
bons, and are not subject to the same decompo- 
sitions as the glycerids. 
905. W hat are the principal glycerids occurring 
in the fixed oils and fats ? 
Tristearin, tripalmitin, and triolein. 
906. How do these three differ in their physical 
properties ? 
Tristearin and tripalmitin are solid at the ordi- 
nary temperature, the former fusing at 68° 
(154°.4 F.), the latter at 50° (122° F.). Triolein 
is liquid at the ordinary temperature and only so- 
lidifies at 0° (32° F.). 
907. To what conditions is the difference in con- 
sistence of the fixed oils and fats due ? 
Partly to the temperature, all fats becoming 
liquid when heated, and the oils solidify when 
cooled sufficiently. At a given temperature the 
consistence depends upon the relative propor- 
tions of triolein on the one hand, and tripalmitin 
and tristearin on the other. 
908. What glycerid of a mineral acid is used in 
the arts, and for what purpose? 
Trinitroglycerol. As an explosive, either CHEMISTRY AND TOXICOLOGY. 
231 
alone or mixed with some inert substance, as in 
dynamite, giant powder, etc. 
( 909. What is an emulsiannk 
A liquid fat in a state of nne and permanent 
subdivision and suspension in a watery fluid. 
Oil and water will not mix under ordinary condi- 
tions ; but if small quantities of certain other 
substances, such as albumen, be added, and the 
two liquids shaken together, an emulsion is 
formed. 
910. Explain the process of saponification? 
It is a double decomposition between a fat and 
an alkali, in which the metallic salt of the acid 
and glycerol are formed : 
(C,H.)'" )n , oK)n 
(C19H360r3 }°3 + 3Hf° 
Tristearin. 
Potassium 
hydroxid. 
= <C£H‘)"'|03 + 3 (Ci8HssOO | o 
Glycerol. 
Potassium 
stearate. 
911. W hat is the source of the fats in the 
body ? 
They are, to a great extent, taken with the 
food in their own form, but are also formed in 
the body from starchy and saccharine sub- 
stances, and even from albuminous substances. 
Animals may be fattened on food which contains 
little fat but is rich in starch. 
912. 11 hat changes do fats undergo in the 
economy ? 
They are oxidized, and their component ele- 232 
ESSENTIALS OP 
ments are finally discharged as C02 and H20. 
This oxidation in the body is attended by the 
liberation of force and heat; a fatty diet is, 
therefore, eminently suited to cold climates, as 
it maintains the body temperature in two ways : 
1st, by the liberation of heat in its oxidation ; 
and 2d, by preventing the loss of heat, the layer 
of fat between the skin and the tissues acting as 
a non-conductor. 
913. State the prominent physical properties of 
fats. 
They are lighter than water, with which they 
do not mix. When liquid fats are shaken with 
water they form globules of varying size, circu- 
lar in outline, and refract light strongly. They 
are soluble in ether, to a certain extent in alcohol, 
and in solutions of the alkalies with formation of 
soaps. They produce a translucent stain on 
paper. 
914. What is a soap, and what is the chemical 
difference between hard and soft soap ? 
A mixture of the stearate, palmitate, and oleate 
of Na or K, the oleate predominating greatly. 
The Na compounds form the hard soaps, and 
the K compounds soft soap. 
915. In what respect does butter fat differ from 
other fats and oils? 
In containing a notable proportion (5 to 8 per 
cent.) of the glycerids of butyric acid and its 
near homologues. These acids themselves differ 
from stearic, palmitic, and oleic acid in being 
soluble in water, and capable of being distilled, 
while the higher acids are insoluble, and are 
decomposed when heated. CHEMISTRY AND TOXICOLOGY. 
233 
916. In what situations in the body do the leci- 
thins and protagon occur? 
In nerve and brain tissue, particularly the gray 
substance, blood corpuscles, blood serum, milk, 
bile, and seminal fluid. 
917. What substances are derived from lecithin 
by decomposition by a base ? 
Glycerophosphoric acid, stearic acid, and cho- 
lin. 
918. What substance other than lecithin is pro- 
duced from the decomposition of protagon? 
A body containing N but not P, called cere- 
brin. 
919. What is a nuclein? 
A phospliorized substance existing in the nu- 
clei or animal and vegetable cells. Nucleins 
from pus, spermatic fluid, brain, and yeast have 
been investigated. They are white, amorphous, 
rather soluble in H20, insoluble in acids and in 
the gastric juice. They are extremely unstable, 
and on decomposition yield phosphoric acid, an 
albuminoid substance, xanthin, hypoxanthin, 
guanin, and adenin. 234 
ESSENTIALS OP 
THIRD SERIES OP HYDROCAR 
BONS. 
SERIES CnH2n—2. 
920. Give the formula, occurrence, and proper- 
ties of acetylene. 
Its formula is C2II2 or It is one of 
the most important constituents of coal gas, and 
is produced by the action of heat upon many or- 
ganic substances. It is a colorless, inflammable 
gas, having a disagreeable odor ; forms an explo- 
sive mixture with air ; detonates on contact with 
Cl in daylight, and combines directly with N un- 
der the influence of electric discharges to form 
hydrocyanic acid. 
TARTARIC ACID. 
921. What is the constitution and basicity of 
tartaric acid t 
COOH 
CHOH 
| = C4H,0,. 
CHOH 
COOH 
It is dibasic, only the 
two hydrogen atoms contained in the groups 
COOH being replaceable. CHEMISTKY AND TOXICOLOGY. 
235 
922. State the properties of tartaric acid. 
Crystallizes in large, hard, transparent prisms ; 
odorless ; having a sour but not disagreeable 
taste. Very soluble in water ; soluble in alcohol. 
The aqueous solution becomes mouldy on stand- 
ing. 
923. Give the composition of seidlitz powders, 
/ and explain the reaction which occurs when their 
\jolutions are mixed. 
The powder in the blue paper is a mixture of 
Rochelle salt (q. v.) and hydro-sodic carbonate ; 
the white paper contains tartaric acid. When 
the solutions are mixed, the carbonate is decom- 
posed by the acid ; sodic tartrate remains in the 
solution, while the liberated C02 produces the 
effervescence. 
924. Give an account of the source of tartaric 
acid and the tartrates. 
The tartrates exist in the juice of the grape 
in notable quantities, and are obtained industri- 
ally as a by-product in the manufacture of 
wine. During the fermentation of wine, the 
must becomes more and more alcoholic, and the 
hydro-potassic tartrate which it contains, being 
less soluble in alcoholic fluids than in water, is 
gradually deposited, forming the crude tartar, or 
“ argol,” of commerce. 
925. What are the chemical name and charac- 
ters of cream of tartar ? 
Hydro-potassic tartrate, obtained by purifying 
crude tartar. A white, crystalline powder, odor- 
less, having a sourish taste ; soluble in 480 parts 
of cold and in 20 parts of hot water ; insoluble in 
alcohol. 236 
ESSENTIALS OP 
926. How is Potasses tartras, U. 8. P., formed, 
and what is its chemical name ? 
By adding hydro-potassic tartrate to solution 
of potassic carbonate, when C02 is liberated and 
potassic tartrate, C4H406K2, is formed. 
927. In what important physical character does 
it differ from hydro-potassic tartrate, and how ? 
It is very soluble in water, while the hydro- 
salt is only sparingly soluble. It has hence re- 
ceived the common name of soluble tartar. 
928. What is the composition of Rochelle salt ? 
It is double tartrate of potassium and so- 
dium : COONa — (CHOH)2 - COOK = C406- 
H4NaK. 
929. What is the composition of tartar emetic ? 
It is a double tartrate of potassium and the ra- 
dical (SbO)': COOK—(CHOH)2 — COO(SbO) = 
C406H4K(Sb0), or antimonyl-potassic tartrate. 
930. State its properties. 
It forms shining, colorless, transparent prisms 
with lAq, or a white powder ; odorless ; having 
a sweetish, unpleasant, metallic taste ; soluble in 
15 parts cold or 2 parts hot water. 
931. Whence is citric acid obtained, and what 
are its characters ? 
From lemon juice. It forms large, colorless 
crystals, with lAq, having a strong acid taste ; 
very soluble in water, the solution becoming 
mouldy by keeping. It is a tribasic acid. 
932. What are the characters of substances of 
this class? 
Substances of unknown constitution, composed 
CARBOHYDRATES. CHEMISTRY AND TOXICOLOGY. 
237 
of C, H, and O, the last two being in the propor- 
tion to form water, i.e., Ha to O. But few of 
them have been obtained artificially, and nearly 
all exist in vegetable and animal bodies. 
Note.—Although the constitution of these substances 
is still uncertain, except that of glucose, whose synthe- 
sis has been accomplished, their reactions show that 
some are alcohols, others aldehydes, and others, like 
glucose, of mixed function. 
933. Into what three groups may they be di- 
vided ? 
1. Glucose group. 2. Cane-sugar group. 3. 
Starch group. 
934. Name the most important member of the 
first group, and give its synonyms. 
Glucose. Grape sugar ; liver sugar ; diabetic 
sugar ; dextrose. 
935. State its chief physical properties. 
Forms yellowish nodules or crystals; very 
soluble in water and in alcohol ; has a sweet 
taste, less marked than that of cane sugar. 
936. How may it be obtained artificially ? 
From cane sugar or starch; either (1) by boil- 
ing with a dilute mineral acid; or (2) by the 
action of a vegetable ferment, called diastase, 
which is formed during the germination of 
grain. 
937. Is sugar a normal or abnormal constituent 
of human urine ? 
It exists normally in quantities too small to be 
distinguished by the ordinary tests. Its presence 
is pathological only when the quantity is so 
increased that it may be detected by the methods 
generally used, the gravity of the disorder 238 
ESSENTIALS OF 
being proportionate to the quantity of sugar 
eliminated. 
938. What precaution is to be observed before 
testing for sugar ? 
The urine should first be tested for albumin. 
If this be present, it should be removed by heat- 
ing the urine to near the boiling point, and filter- 
ing from the coagulum. 
939. Describe Fehling’s test. 
Place in a test tube about 1 c.c. Fehling’s solu- 
tion (see Manual, p. 380), and boil; no reddish 
tinge should be observable, even after five min- 
utes’ repose. Add the liquid under examination 
gradually, and boil after each addition. In the 
presence of sugar a yellow or red precipitate is 
formed. In the presence of traces of glucose, 
only a small amount of precipitate is produced, 
which adheres to the glass, and is best seen when 
the blue liquid is poured out. 
940. Describe Trommer's test. 
To the urine, in a test tube, add one or two 
drops of a solution of cupric sulfate, and then 
about half as much Liq. potassse as there was 
urine ; shake and boil. If sugar be present, a 
yellow or red precipitate of cuprous oxid is 
formed. In applying Fehling’s or Trommer’s 
test to urine, a dirty yellowish-green color is 
frequently observed ; this is not due to the pre- 
sence of sugar. 
941. Explain the principles upon which Trom- 
mer's and Fehling's tests are based. 
By the action of the boiling alkali, glucose is 
converted into substances (glucic and melassic 
acids) which are very prone to oxidation, and are CHEMISTRY AND TOXICOLOGY. 
239 
consequently good reducing agents ; if cupric 
sulfate be present, it is converted into cuprous 
sulfate, and this in turn decomposed with depo- 
sition of cuprous oxid. As there is deoxidation 
of the copper compound, these tests are spoken 
of as “ reduction tests.” 
942. Describe Boettger's test. 
Render the liquid strongly alkaline by addi- 
tion of Na2C03. Divide about 6 c.c. of the alka- 
line liquid in two test tubes. To one test tube 
add a very minute quantity of powdered subni- 
trate of bismuth, to the other as much powdered 
litharge. Boil the contents of both tubes. The 
presence of glucose is indicated by a dark or 
black color of the bismuth powder, the litharge 
retaining its natural color. 
943. How is the fermentation test conducted? 
Take three test tubes. A, B, and C, place in each 
some washed yeast; fill A completely with the 
urine to be tested, and place it in an inverted po- 
sition, the mouth below the surface of some of 
the same urine in a flat vessel (the entrance of air 
being prevented, during the inversion, by closing 
the opening of the tube with the finger until it 
has been brought below the surface of the urine). 
Fill B completely with some urine to which glu- 
cose has been added, and C with distilled water, 
and invert them in the same way as A ; B in 
saccharine urine, and C in distilled water. Leave 
all three tubes in a place where the temperature 
is about 25° (77° F.), for twelve hours, and then 
examine them. If gas have collected in B over 
the surface of the liquid, and none in A, the urine 
is free from sugar. If gas have collected in both 240 
ESSENTIALS OP 
A and B, and not in 0, the urine contains sugar. 
If no gas have collected in B, the yeast is worth- 
less, and if any gas be found in C the yeast itself 
contains C02. In the last two cases the process 
must be repeated with a new sample of yeast. 
944. Describe Robert’s method for determining 
the quantity of sugar in urine. 
The specific gravity of the urine is carefully 
observed at 25° (77° F.); yeast is then added and 
the urine maintained at 25° (77° F.) until fer- 
mentation has stopped ; the sp. gr. is again ob- 
served, when it will be found lower than before. 
Each degree of diminution of sp. gr. represents 
0.2196 grm. of sugar in each 100 c c. of urine. 
(For more accurate methods, see Manual, pp. 
379-381.) 
945. Under what normal conditions may the 
urine contain glucose in quantity sufficient to re- 
spond to the tests ? 
1. In the urine of women during pregnancy 
and lactation. 2. In the urine of old persons. 
3. With a diet rich in starch or sugars. 
946. Under what pathological conditions may 
the urine contain sugar in considerable quantity ? 
1. In abnormally stout persons. 2. In diseases 
attended with interference of the respiratory 
function. 3. In diseases attended with inter- 
ference of the hepatic circulation. 4. In many 
cerebral and cerebro-spinal diseases. 5. In inter- 
mittent and typhus fevers. 6. As a result of the 
action of carbon monoxid, arsenic, and the anses- 
thetics. 7. In diabetes mellitus. 
947. II hat are the characters of urine in dia- 
betes mellitus f 
It is excessive in quantity, pale in color, of CHEMISTRY AND TOXICOLOGY. 
241 
high specific gravity, and contains sugar, some- 
times as much as 20 to 40 ounces being voided 
daily. 
(See Manual, pp. 375-377.) 
948. Give the formulae of grape and cane sugars. 
Grape sugar, CeHi206 ; cane sugar, Ci2H22- 
On. 
949. W hat are the main points of difference be- 
tween grape and cane sugars? 
Cane sugar is more easily and perfectly crys- 
tallizable, more soluble, and sweeter than glu- 
cose. It also differs from glucose in not being 
directly capable of fermentation, and in not re- 
acting with the reduction tests for sugar. 
950. Describe the action of heat on cane sugar. 
When heated to 160° (320° F.) it melts, and, on 
cooling, forms an amber-colored solid known as 
“ barley sugar.” If the heat be continued to 210° 
(410° F.), a brown, tasteless mass, known as 
“burnt sugar”or “caramel,” remains. This is 
tasteless, soluble in water or dilute alcohol, and 
is largely used to give color to confectionery and 
spirits. 
951. Where is milk sugar found? Describe its 
characters. 
In milk. Crystallizes in hard, white prisms. 
It is the least soluble of all sugars in water, and 
is insoluble in alcohol. It enters into alcoholic 
fermentation with difficulty. In presence of de- 
composing albuminous matter, and under certain 
other influences, it undergoes a peculiar fermen- 
tation, known as the lactic, resulting in the for- 
mation of carbon dioxid, alcohol, and lactic acid. 
It reacts readily with the reduction tests. 
16 242 
ESSENTIALS OF 
952. Where does starch exist in nature ? 
In all plants. The main sources from which it 
is obtained are potatoes and cereals. It does not 
exist in animal tissues or fluids. 
953. Give its physical characters. 
It forms a white, shining powder, or, if dried 
in bulk, columnar masses. When examined mi- 
croscopically it is found to consist of round or 
egg-shaped granules, differing in size and ap- 
pearance with the source from which it was ob- 
tained. When heated, the granules swell and 
split into concentric layers. Almost insoluble in 
water, but, if soaked or boiled in water, the gran- 
ules swell, burst, and finally form a gelatinous 
mass known as “hydrated starch,” or starch 
paste. 
954. Describe the action of mineral acids on starch. 
When boiled with dilute mineral acids, starch 
is converted into glucose. Hot, concentrated ni ■ 
trie acid converts it into oxalic acid. Cold, fum- 
ing nitric acid dissolves it, forming an explosive 
nitro-compound. 
955. Give a test for starch. 
Solution of iodin with starch gives a dark vio- 
let-blue color, which disappears on warming, and 
returns on cooling. This reaction is characteristic 
and very delicate. 
956. What articles of food are composed entirely 
of starch? 
Sago, tapioca, arrowroot. 
957. What proportion of starch is contained in 
wheat and rice ? 
Wheat contains about 70 per cent., and rice 90 
per cent. CHEMISTRY AND TOXICOLOGY. 
243 
958. What action have diastase, ptyalin, and 
the pancreatic juice upon starch ? 
They first convert it into “ soluble starch.” 
This is subsequently decomposed into different 
modifications of dextrin (“ erythrodextrin ” and 
“ achrobdextrin ”) and maltose. The maltose is 
more or less completely converted into glucose. 
959. What action has dry heat upon starch ? 
The granules are ruptured, and the starch is 
converted into dextrin. 
960. What action has boiling II20 upon starch ? 
The granules swell and finally burst, forming an 
opalescent solution of “soluble starch,” which 
becomes gelatinous on cooling. 
961. Vthat is cellulose ? 
A substance having the same percentage com- 
position as starch, and forming the basis of all 
vegetable fibre. It exists almost pure in absorb- 
ent cotton and Swedish filter paper. 
962. Give the formula of starch and cellulose. 
CoHioOs, or a multiple thereof. 
963. Explain the action of nitric acid upon cel- 
lulose. 
By acids of different concentration one, two, 
or three times the group (N02) replaces one, two, 
or three atoms of hydrogen of cellulose, to form 
mono-, di-, and tri-nitro cellulose. 
964. How do these three differ, and for what 
purposes are they used ? 
In the violence with which they explode on be- 
ing ignited in a confined space, the force of the 
explosion increasing with the number of groups 
(N02) substituted ; and in their solubility in a 
mixture of alcohol and ether, the dinitro-prod- 
uct being the most soluble. Trinitro-cellulose is 244 
ESSENTIALS OF 
sometimes used as a substitute for gunpowder 
under the name gun-cotton. Dinitro-cellulose, or 
pyroxylin, dissolved in a mixture of alcohol and 
ether, forms the collodion used in photography 
and as a styptic. 
965. Where is glycogen found, and what are its 
properties? 
In the liver of all animals. It closely resem- 
bles starch in its properties ; a white, odorless, 
tasteless, amorphous powder ; swells up in cold 
water, forms an opalescent solution with hot 
water ; does not react with any of the tests for 
glucose, into which substance it is, however, 
readily converted by the same agents which con- 
vert starch into glucose, as well as by some sub- 
stance existing in the liver and in blood. 
966. How is commercial dextrin made, and what 
are its properties ? 
By subjecting starch to a dry heat of 170° 
(347° F.); or by heating starch to 90° (194° F.) 
with dilute H2S04. It is a yellowish-white 
powder or a yellow solid, resembling gum arabic 
in appearance. It is soluble in HaO, forming 
mucilaginous solutions ; insoluble -in alcohol. It 
is not capable of fermentation. It reduces cupro- 
potassic solutions at 85° (185° F.). Its solutions 
are dextrogyrous. It is used for the same pur- 
poses as gum arabic under the name “British 
gum.” 
967. In what respects do erythrodextrins and 
achroodextrins differ from each other? 
The former are colored red by iodin, the latter 
are not. They also differ in their rotary and re- 
ducing powers, and in that the former are much 
more readily converted into sugar than the latter. CHEMISTRY AND TOXICOLOGY. 
245 
CYCLIC HYDROCARBONS AND 
THEIR DERIVATIVES. 
968. Why is this series designated as aromatic ? 
Most of the substances included in it which 
exist naturally have strong and aromatic odors. 
969. Of what substance are all the members of 
this series derivatives ? 
Of benzene; CflHs. 
970. Explain the constitution of benzene, and 
how the other aromatic substances are derived from 
it. 
There is a very important difference between 
the constitution of the aromatic substances and 
that of those heretofore considered. In the latter, 
the atoms of carbon are arranged in an open 
chain, the carbon atoms of which exchange be- 
tween each other one, two, of three valences : 
AROMATIC SERIES. 
c=h3 
I 
c=h3 
C=H, 
II 
0=11, 
C—H 
III 
C—H 
Ethyl 
hydrid. 
Ethylene. 
Acetylene. 
In the case of benzene, however, the carbon 
are not pranged in an open chain, but ju 246 
ESSENTIALS OP 
a closed one, the six C atoms alternately exchang- 
ing one and two valences: 
\ /(^x / 
Nc c/ 
c A 
/\ 
I 
There remain six free valences. When these 
are all satisfied by hydrogen the resulting sub- 
stance is benzene. They may, however, be satis- 
fied by other elements, radicals, or lateral chains 
(see Q. 695), to produce the substances directly 
derived from benzene. More complex hydrocar- 
bons and their derivatives are also produced by 
the union or fusion of two or more benzene 
nuclei, as the group C6, figured above, is called. 
Still other compounds are obtained by the elimi- 
nation of one or more of the carbon atoms of the 
benzene nucleus to form pentagonal or quadratic 
nuclei, and derivatives therefrom : 
~c — c— 
II II 
-c c— 
\ / 
c 
/ \ 
\ / 
c—c 
II II 
c—c 
/ \ 
Or the linkage in the benzene nucleus may be 
altered to increase the valence of the group, as in; CHEMISTRY AND TOXICOLOGY. 
247 
\ / 
c 
/ \ 
—c — c— 
4-A- 
\ / 
c 
/ \ 
\ / 
c 
)c/ 
9 9 
x \ / x 
c 
/ \ 
Or, further, another element may be substituted 
for one or more atoms of carbon in any of the 
above nuclei, as in : 
A 
/ \ 
—c c— 
4 o- 
\ / 
N 
—c — c— 
ii : ii 
—c n 
\ / 
N 
I 
BENZENE AND ITS DERIVATIVES. 
971. Whence is benzene obtained, and what are 
its uses ? 
It is obtained, with other hydrocarbons closely 
related to it, from coal tar. Its most important 
use is as the starting point in the manufacture of 
anilin dyes. It is also used as a solvent for cer- 
tain alkaloids. 
972. Tinder what other names is benzene known ? 
Benzol. Phenyl hydrid. 248 
ESSENTIALS OP 
973. State its principal properties. 
It is a colorless liquid ; boils at 80°.5 (176°.9 
F.), and solidifies at 4°.5 (40*.1 F.); does net 
mix with water; burns with a smoky flame. 
Pure benzene has an agreeably, the commercial 
article an unpleasant odor. 
974. How are the superior homologues of benzene 
derived from itf 
By the substitution of CnH»n-fi for H, thus : 
H 
I 
C 
/ \ 
H—C C—H 
I II 
H—C C—II 
% / 
C 
I 
H 
Benzene. 
H 
I 
C 
/ \ 
H—C C—CHs 
I II 
II—C C—H 
% / 
C 
I 
H 
Toluene. 
The group (or groups) so substituted is known 
as a “ lateral chain,” to distinguish it from the 
benzene nucleus. 
075. Explain what is meant by orientation. 
When a single atom or radical or lateral chain 
is substituted in a benzene molecule, it is immate- 
rial in what position it is introduced; there is but 
one such derivative. When, however, the num- 
ber of substitutions is two or more, their relative 
positions or “orientation” become important, 
because with different orientation distinct sub* CHEMISTRY AND TOXICOLOGY. 
249 
stances are formed. To distinguish these the 
carbon atoms are numbered, the upper being arbi- 
trarily designated as 1, as in formula I: 
ch3 
A 
lie C—H 
II I 
HC C-CH3 
\c/ 
H 
/°x 
C 6 1 2 C 
II I 
C5.3C 
i. 
II. 
With a bisubstituted derivative there are three 
possible relations: 1. Consecutive, designated by 
the prefix ortho, in 1-2; 2-3; 8-4; 4-5; 5-6 or 
6-1; 2. TJnsymmetrical, designated by the prefix 
meta, in 1-3 ; 2-4; 3-5 ; 4-6 ; 5-1 or 6-2 ; and 3. 
Symmetrical, designated by the prefix para, in 
1-4; 2-5; or 3-6. Thus the compound whose 
formula is given above II. is metadimethyl ben- 
zene. Differences in orientation also occur fre- 
quently in the more complex compounds, which 
will be considered later. 
976. What substance results from the substitu- 
tion of a group {OH) for an atom of hydrogen in 
benzene ? 
Phenol. Commonly known as carbolic or 
phenic acid. 250 
ESSENTIALS OF 
977. Write the graphic formula of phenol. 
OH 
C " 
H-C7 XC—H 
II I 
H—CL .0—H 
\cf 
I 
H 
978. Wherein do the phenols differ from the al- 
cohols ? 
They do not furnish aldehydes and acids by 
oxidation. They are not decomposed into hydro- 
carbons and water by dehydrating agents. They 
do not react with acids to produce ethers. 
979. State the properties of phenol. 
It crystallizes in long, colorless needles, which 
fuse at 35° (95° F.). It has a peculiar odor, and 
a burning, bitter taste. Soluble in 20 parts of 
water, quite soluble in alcohol and in ether. It is 
a powerful antiseptic agent, coagulates albumen, 
and prevents fermentation. 
980. Describe the analytical reactions of phenol. 
1. Its peculiar odor. 2. Mix with one-quarter 
volume NH4HO soln. ; add two drops .NaCIO 
soln. and warm; a blue or green color, which 
turns red on addition of HC1 to acid reaction. 
3. Add two drops of liquid to a little HC1, add 
one drop IIN03 ; a purple-red color. 4. Boil 
with HNOs; neutralize with KHO ; a yellow, 
crystalline precipitate. 5. With FeS04 soln., a CHEMISTRY AND TOXICOLOGY. 
251 
lilac color. 6. Float on H3SO4, add powdered 
KNO3 ; a violet color. 
981. Describe the symptoms of phenol poisoning. 
Those portions of the skin and mucous mem- 
brane which have been in contact with the poison 
are whitened and hardened. There are burning 
pains in the mouth, oesophagus, and stomach, 
and vomiting ; lowering of the pulse and tem- 
perature, contraction of the pupils, stupor, syn- 
cope, and collapse, terminating in death. The 
urine, clear and of the normal color when voided, 
becomes rapidly greenish, and finally dark olive 
green or almost black. 
982. What treatment should be adopted in 
poisoning by phenol ? 
The administration of emetics, or the use of the 
stomach pump, used with great caution; albu- 
men (raw white of egg); and stimulation. 
983. How is picric acid derived from phenol? 
By boiling phenol with HN03, three atoms of 
II are removed from the former substance, and 
are replaced by three groups (NOa)', with forma- 
tion of CbH3(OH)(N02)3 = trinitrophenol = pic- 
ric or carbazotic acid. 
984. State the properties of trinitrophenol. 
Forms prismatic, sulfur-yellow crystals, very 
bitter, sparingly soluble in water, quite soluble in 
alcohol or ether. It is acid in reaction, and forms 
saltscalled picrates These are all decomposed 
by heat, usually with an explosion. Its coloring 
power is very intense, and it is used in dyeing. 
(For other Phenol Derivatives, Diatomic 
and Triatomic Phenols, and Phenol Dyes, 
see Manual, pp. 404-411.) 252 
ESSENTIALS OF 
985. Explain the relations between benzoic alco- 
hol, benzoic aldehyde, and benzoic add, and give 
their graphic formulae. 
Benzoic alcohol is benzene, one of whose II 
atoms has been replaced by the group CHaOH, 
characteristic of the monoatomic alcohols (see 
Q. 717). Benzoic aldehyde is derivable from it 
by oxidation, limited to the removal of two H 
atoms (see Q. 761). Benzoic acid is derivable 
from benzoic aldehyde or alcohol by more com- 
plete oxidation, attended by introduction of an O 
atom (see Q. 745). 
The graphic formulae are : 
. CHaOH 
/X 
H—C C—H 
II I 
H—C C-H 
\/ 
C 
I 
II 
COH 
/X 
H—C C—H 
II I 
H—C C—H 
X/ 
C 
I 
H 
COOH 
/X 
II—C C—H 
II I 
H—C C—H 
\/ 
C 
I 
H 
Benzoic 
alcohol. 
Benzoic 
aldehyde. 
Benzoic 
acid. 
986. Of what oil is benzoic aldehyde the chief 
constituent, and what are its most prominent 
properties ? 
Oil of bitter almonds. It is a colorless oil, 
sparingly soluble in water, readily converted by 
oxidizing agents into benzoic acid. It is, when 
pure, non-poisonous, the toxic powers of the 
commercial oil of bitter almonds being due to 
the presence of hydrocyanic hcid- CHEMISTRY AND TOXICOLOGY. 
253 
987. How does benzoic acid exist in nature, and 
how is it obtained? 
It exists in a number of resins and balsams, 
notably in benzoin, from which it is obtained by 
sublimation. The benzoin is placed in a porcelain 
capsule, covered with filter paper, over which is 
a cone of writing paper. On heating the capsule 
the acid is volatilized, passes through the filter 
paper, and condenses in the cone. 
988. State the properties of benzoic acid. 
It crystallizes in long, white, flexible needles, 
or in thin laminae, which fuse at 122° (251 “.6 F.) 
and sublime at 145° (293° F.). Sparingly soluble 
in cold water, more soluble in boiling water, 
easily soluble in alcohol, ether, and the fatty and 
ethereal oils. When pure, it is odorless and has 
a faint acid taste. 
989. Into what substance is benzoic acid con- 
verted in passing through the animal economy ? 
Hippuric acid. 
990. Give the occurrence and properties of hip- 
puric acid. 
It is found in human urine in small and vari- 
able quantities, and abundantly in that of the 
herbivora. It crystallizes in long, colorless 
prisms; sparingly soluble in cold, readily soluble 
in hot water and in alcohol. It is monobasic. 
When heated alone, when boiled with the mine- 
ral acids or alkalies, and under the influence of 
certain ferments, as in putrid urine, it is decom- 
posed, with formation of benzoic acid. 
991. What is the constitution of salicylic acid? 
It has the same relation to phenol that benzoic 
acid has to benzene. It is, therefore, phenol in 254 
ESSENTIALS OF 
which an atom of hydrogen has been replaced by 
the group (CO.H)': C6H4(OlI)COOH = CTH,03. 
992. How does it exist in nature, and how is it 
prepared ? 
It exists, as its methylic ether, in oil of winter- 
green, from which it may be obtained. It is, 
however, more cheaply prepared by the combined 
action of sodium and carbonic anhydrid upon 
phenol. 
993. State its properties. 
It crystallizes in colorless prisms; odorless; has 
a sweetish sour taste; fuses at 158° (316°.4 F.). 
At moderately elevated temperatures it sublimes; 
at higher temperatures, or when rapidly heated, 
it is decomposed into phenol and carbon dioxid. 
Sparingly soluble in cold, readily soluble in warm 
water and in alcohol or ether; its solutions are 
acid. It is a monobasic acid. It is a valuable 
disinfectant. 
994. How is gallic acid obtained ? 
By exposing moistened gall nuts to the air for 
a mouth or more. Under the influence of a pecu- 
liar ferment, the tannic acid of the galls is con- 
verted into gallic acid, which is then extracted 
by subjecting the pasty mass to pressure, and 
purified by solution, filtration through purified 
animal charcoal, and crystallization. 
995. Give the principal properties of gallic acid. 
It forms white, silky needles with lAq. Odor- 
less; has a sweetish, astringent taste, and an acid 
reaction; sparingly soluble in cold, readily soluble 
in hot water, and abundantly soluble in alcohol. 
It does not precipitate gelatin or the alkaloids 
from their solutions (distinction from tannin). CHEMISTRY AND TOXICOLOGY. 
255 
When heated to 210° (470° F.), it is decomposed 
into pyrogallol (= pyrogallic acid) and carbon 
dioxid. 
996. How is nitrobenzol obtained, and what re- 
lation does it bear to benzene ? 
By the action of fuming HNOs on benzene. It 
is benzene in which one H atom has been displaced 
by NO, = C8H6(N02). 
997. Under what other names is it known, and 
what are its properties and uses ? 
It is known as essence of mirbane, or artificial 
oil of bitter almonds. It is a yellow, oily liquid, 
having the odor of bitter almonds; very sparingly 
soluble in water, but poisonous. It is used as a 
substitute for oil of bitter almonds, but princi- 
pally in the manufacture of anilin. 
998. Explain the constitution of anilin and its 
formation from nitrobenzene. 
It is benzene in which one H is replaced by the 
group (NH,)'. It may also be considered as 
phenylamin, i.e., ammonia in which one H has 
been replaced by the radical phenyl, (C8H8)'. 
By the action of reducing agents upon C«H6- 
(NO)2, the 02 is removed, and H2 substituted: 
C«H.(NO), + 3H2 = C8H.(N'"H,)' + 2HaO. 
999. Describe the physical properties of anilin. 
When pure, it is a colorless, oily liquid, of a 
peculiar, aromatic odor, boiling at 184°.8 (864° 6 
F.), sparingly soluble in water. The commer- 
cial product is brown, and has the odor of coal 
tar. 
1000. For what purpose is anilin used in the 
arts? 
In the manufacture of a great number of 256 
ESSENTIALS OF 
brilliant dyes, the most important of which is the 
red magenta or fuchsin. 
(See Manual, pp. 435, 436.) 
1001. How is antifebrin related to anilin. 
It is acetanilid, i.e., anilin in which one hy- 
drogen atom has been replaced by the radical 
(C2H30) of acetic acid : C»H,(NH.CaHsO). 
(For Phenylamins, Hydrazins, Azo- and 
Diazo derivatives, see Manual, pp. 420-422.) 
PYRIDIN BASES. 
1002. Write the graphic formulae of benzene and 
of pyridin. 
H 
C 
/\ 
HC CH 
I II 
HC CH 
\/ 
C 
H 
H 
C 
/ \ 
HC CH 
I II 
HC CH 
\/ 
N 
1003. Describe the source and properties of py- 
ridin. 
It exists in oil of Dippel, or bone oil, produced 
by the dry distillation of bones, hoofs, etc., and 
is a product of decomposition of piperidin. It is 
a colorless liquid, having a very penetrating 
odor. Is strongly alkaline and combines with 
acids to form salts in the same manner as ammo- 
nia. It is therefore an alkaloid (see Q. 1023) of 
animal origin. 
Benzen*. 
Pyridin. CHEMISTRY AND TOXICOLOGY. 
257 
(For superior homologues and other derivatives 
of pyridin, see Manual, pp. 423-429.) 
1004. Explain by graphic formula the relation 
between pyridin and piperidin. 
H 
C 
/ \ 
HC CH 
I II 
HC * CH 
X / 
N 
h2 
c 
/ \ 
HaC CH, 
I I 
h2c ch3 
\ / 
N 
H 
1005. Name four vegetable alkaloids which are 
derivatives of piperidin, and the sources whence 
they are obtained. 
Piperin. from black and white pepper; Coniln, 
from Conium maculatum; Atropin, from Atropa 
belladonna ; Cocai'n, from Erythroxylon coca. 
1006. How is coniin related to piperidin? 
It is piperidin in which (C3H7) has been substi- 
tuted for H. Its formula is therefore C6NHi0- 
(C3H7). It has been obtained synthetically from 
picolin, a superior homologue of pyridin. 
1007. Describe the properties of coniin. 
It is an oily liquid, lighter than HaO, having a 
disagreeable, penetrating odor; sparingly soluble 
in HaO, readily in alcohol and ether. It has a 
strongly alkaline reaction and forms neutral, 
amorphous salts with most acids. It deteriorates 
rapidly on exposure to air, becomes colored, and 
finally resinous. 
Pyridin. 
Piperidin. 
17 258 
ESSENTIALS OF 
1008. Describe the 'prominent symptoms of poison- 
ing by hemlock or its alkaloid. 
The action of the plant begins in a half-hour 
or less, that of the alkaloid almost immediately. 
There are headache, derangement of vision, with 
dilated and fixed pupils, interference with deglu- 
tition, and great drowsiness. Muscular weakness, 
increasing to paralysis, begins at the extremities 
and extends to the muscles of respiration, causing 
death by apncea in from one to three hours. 
1009. What treatment should be followed? 
The unabsorbed poison is to be removed by the 
pump or emetics. Stimulants are indicated, and 
the performance of artificial respiration. 
1010. What are the characters of atropin ? 
' It crystallizes in silky needles, having a faint 
yellowish tinge and persistent, bitter taste; odor- 
less ; sparingly soluble in water, readily in alco- 
hol. 
1011. What salt of atropium is used in medi- 
cine ? 
The sulfate. 
1012. Describe the prominent symptoms of poison- 
ing by atropin or belladonna. 
Giddiness, drowsiness, great thirst, dryness of 
the mouth and fauces, and difficulty in degluti- 
tion. The pulse is stronger than normal, the 
countenance is flushed, the eyes sparkling and 
prominent, with widely dilated pupils and dis- 
turbances of vision. The power of articulation is 
lost early. The extremities are the seat of partial 
paralysis, preceded by numbness. Later there is 
delirium, sometimes maniacal, sometimes attended 
with pleasing hallucinations or spectral illusions. CHEMISTKY AND TOXICOLOGY. 
259 
In fatal cases, the patient passes into a condition 
of coma terminating in death. In cases of re- 
covery, the patient sleeps quietly, and awakes 
unconscious of previous mental disturbances. 
1013. How should cases of poisoning by this and 
other alkaloids be treated ? 
The chief indication is to remove any portion 
of the poison remaining in the stomach, as rap- 
idly as possible ; an emetic of zinc sulfate should 
be given, or, if this be not feasible, a hypodermic 
injection of apomorphin. The stomach pump 
should be used and the stomach washed out with 
infusion of tea, or with water holding powdered 
animal charcoal in suspension. Chemical anti- 
dotes are of little value. Where physiological 
antidotes exist they should be used. 
(For constitution of and tests for atropin and 
cocai'n, see Manual, pp. 427, 428.) 
COMPOUNDS WITH PENTAGONAL NUCLEI. 
1014. Give the graphic foi'mulce of pyrrol and ctf 
iodol. 
HC —CH 
II II 
HC CH 
\ / 
N 
H 
IC—Cl 
II II 
IC Cl 
\ / 
N 
H 
1015. What important medicine is a derivative 
of pyrrol f 
Antipyrin. (See Manual, pp. 430-432.) 
Pyrrol. 
Iodol (Tetriodopyrrol.) 260 
ESSENTIALS OF 
DERIVATIVES OF INCOMPLETE BENZENIC 
HYDROCARBONS. 
1016. Is cholesterin related to the fats, and what 
is its constitution ? 
It is not. It is an alcohol, having the compo- 
sition (C’«H<|)' J. o. 
1017. State the physical characters of cholesterin. 
A white solid, crystallizing in plates or nee- 
dles ; tasteless, odorless, unctuous to the touch, 
insoluble in water, sparingly soluble in cold alco- 
hol, and readily in hot alcohol or ether. Melts 
at 145° (293° F.). 
1018. Give some of the reactions of cholesterin. 
Treated with HN03, the solution evaporated 
nearly to dryness and NH4HO added : a brick- 
red color. With sulfuric acid and chloroform, a 
red color, changing to violet, blue, green. Not 
affected by potash solution. 
1019. In what parts of the economy does it oc- 
cur ? 
In blood, bile, nerve tissue. Pathologically in 
gall stones, fluids of hydrocele and of certain 
cysts. Tumors consisting almost entirely of cho- 
lesterin have occurred in the brain. 
1020. What are the cholesterids ? 
Ethers of cholesterin, formed by the union of 
fatty acids with cholesterin, and corresponding 
to the glycerids (see Q. 902-905) and other com- 
pound ethers (see Q. 757). Such cholesterids 
constitute lanolin, a neutral, fatty substance ob- 
tained from wool fat and used as a vehicle in 
ointments. CHEMISTRY AND TOXICOLOGY. 
261 
1021. IIow are the hi- and polybenzoic hydrocar- 
bons constituted ? 
By the linking or fusion together of two or 
more benzene nuclei. 
1022. Name the more important of these hydro- 
carbons, and indicate in what connection they are 
of interest. 
Triphenylmethan, a base many of 
whose derivatives are used as anilin dyes; Di- 
phenyl, (CeHsXCsHs), one of whose derivatives, 
Dipyridyl, (C«NH4)(C«NH4), is the nucleus of the 
alkaloid nicotin ; Phenanthrene, Ci4Hi0, which is 
the nucleus of the alkaloids morphin and codein ; 
Naphthalene, Ci0H8, some of whose derivatives 
are used as dyes, others, the Naphthols, corre- 
sponding to the phenols, as antiseptics, and one 
of whose derivatives, Quinolin. C9H7N, is the 
nucleus of the cinchona alkaloids ; Anthracene, 
C14H10, from which artificial madder, or Aliza- 
rin. is obtained. 
(See Manual, pp. 434-450.) 
BI- AND POLYBENZOIC HYDROCARBONS. 
ALKALOIDS. 
1023. What is an alkaloid ? 
An organic, nitrogenized substance, alkaline in 
reaction, and capable of combining with acids to 
form salts, in the same way as does ammonia. 
They are sometimes known as vegetable bases or 
alkalies. 
1024. Into what two classes are the alkaloids di- 
vided, and wherein do they differ? 
Volatile and fixed. The volatile alkaloids are 262 
ESSENTIALS OP 
oily, readily volatile without decomposition, and 
consist of C, H, and N. The fixed alkaloids are 
for the most part solid and crystalline, not, or 
only partially volatile without decomposition, 
and consist of C, H, N, and O. 
1025. Describe the behavior of the alkaloids and 
of their salts toward solvents. 
As a rule, the free alkaloids are insoluble or 
very slightly soluble in water, more soluble in 
chloroform, petroleum ether, benzene, and amy- 
lic alcohol. Their salts are insoluble in the last- 
named solvents, but generally soluble in water 
and in alcohol. 
1026. How should the names of the alkaloidal 
salts be constructed ? 
In the same way as those of the corresponding 
ammoniacal salts : thus, as ammonm combines 
with hydrochloric acid to produce ammonw 
chlorid, so morphia (or morphin) combines with 
the same acid to produce morplntm chlorid. 
1027. Describe some of the general reactions of 
the alkaloids. 
They are precipitated from solutions of their 
salts by KHO, NaHO, NH4HO, CaH202, BaH2- 
Oa, and MgO. Their solutions form yellowish 
or white precipitates with solutions of phospho- 
molybdic acid, potassium iodhydrargyrate, and 
other “ general reagents.” 
1028. Name the principal volatile alkaloids. 
Nicotin, coniin, spartei'n. 
1029. Give the source and properties of nicotin. 
It is obtained from tobacco. It is an oily, col- 
orless. transparent liquid, heavier than water, 
having a burning taste and a faint odor of to- chemistry and toxicology. 
263 
bacco, which becomes more powerful upon the 
application of heat; it is quite volatile, and its 
vapors are very irritating. Very soluble in 
water, alcohol, and ether. When exposed to the 
air it absorbs moisture, becomes brown, and is 
oxidized. It is very alkaline, and forms well-de- 
fined salts with acids. It is a very violent poi- 
son, and very rapid in its action, 
1030. Describe the prominent symptoms of poi- 
soning by tobacco or nicotin. 
The alkaloid has caused death in three min- 
utes, tobacco in fifteen minutes. The patient 
first suffers from giddiness, trembling of the 
limbs, depression, cold sweats, and confusion of 
intellect. The pulse gradually becomes weaker, 
the respiration more difficult, and paralysis more 
extended. Death is usually preceded by convul- 
sions. 
1031. What should be the treatment in nicotin 
tobacco poisoning? 
Wash out the stomach with water, or better, 
with infusion of tea holding charcoal in suspen- 
sion ; opium, stimulants. 
OPIUM ALKALOIDS. 
1032. Name the principal alkaloids existing in 
opium. 
Morphin, codein, narcein, narcotin, thebaiin, 
papaverin. 
1033. In what form do these probably exist in 
opium ? 
In combination with a peculiar organic acid 
known as meconic acid, or with lactic acid. 264 
ESSENTIALS OE 
1034. State the properties of morphin. 
It crystallizes in colorless, transparent, odor- 
less prisms, having a persistent, bitter taste ; sol- 
uble in 500 parts of boiling water, insoluble in 
ether and chloroform, soluble in 13 parts of boil- 
ing alcohol. Morphin and its salts are very 
prone to oxidation. 
1035. What salts of morphium are officinal f 
The acetate, chlorid, and sulfate. 
1036. Give tests for the presence of mcyrphin. 
1. It is colored orange, changing to yellow, by 
IINO3. 2. If iodic acid and a drop of chloro- 
form be added to solution of a morphin salt, free 
iodin is liberated, which colors the chloroform 
violet. If now dilute NH4HO be floated on the 
liquid, a dark brownish zone is formed. 3. 
Solution of neutral Fe2Cl8 gives a blue color 
with morphin. 4. Moisten the solid with IIC1 to 
which a small quantity of H2S04 has been added, 
evaporate on the water bath until the HC1 is ex- 
pelled: a violet-colored, liquid residue remains. 
Add to this some IIC1, and neutralize with solid 
ISallCOs in slight excess : a pink or rose color is 
produced, most distinctly visible on the bubbles. 
Add a drop of H20 and a drop or two of tincture 
of iodin : a green color. 5. Moisten the solid 
with concentrated 1I2S04, and heat cautiously 
until white fumes just begin to appear, cool, and 
touch the liquid with a glass rod moistened with 
dilute HNOa: a fine blue-violet color, changing 
to red and then to orange. 6. Frohde’s reagent 
(a fresh solution of ammonium molybdate in con- 
centrated H2S04) gives a violet color, changing 
to blue, dirty green, and faint pink. CHEMISTRY AND TOXICOLOGY. 
265 
1037. What relation does apomorphin bear to 
morphin, and how is it produced ? 
It is morphin minus HaO. It is produced by 
heating morphin with HC1 to 150° (302° F.) un- 
der pressure. 
(See Manual, pp. 440-445.) 
1038. Give a test for the presence of meconic 
acid. 
With a solution of neutral Fe2Cl6 a red color 
is produced, which is not discharged upon the 
addition of mineral acids or of solution of 
HgCla. 
1039. How much morphin does opium contain ? 
Ten to fifteen per cent. 
1040. Which is the most actively poisonous of 
the opium alkaloids ? 
Theba'in. 
1041. Describe the prominent symptoms of poi- 
soning by opium and its preparations. 
At first there is usually a period of excitation, 
marked by restlessness, great physical activity, 
loquacity, and hallucinations. The patient then 
becomes weary, dull, and drowsy ; he yields to 
the desire for sleep, from which at first he may 
be roused. The lips are livid, the face pale, the 
pupils contracted, and the surface bathed in per- 
spiration. The condition of somnolence rapidly 
passes into narcosis. The patient cannot be 
roused, and lies motionless and senseless, with 
completely relaxed muscles. The pulse, at first 
full and strong, becomes feeble, slow, irregular, 
and easily compressible; the respiration slow, 
shallow, stertorous, and accompanied by mucous 
rales. The patient rapidly becomes comatose, 266 
ESSENTIALS OP 
and, in fatal cases, dies in from forty-five minutes 
to fifty-six hours, usually in from twelve to 
eighteen hours. In cases of recovery after the 
stage of narcosis, the pulse and respiration grad- 
ually return to the normal, and the condition of 
coma passes into one of deep sleep, lasting twen- 
ty-four to thirty-six hours. 
1042. What treatment should be followed in 
opium poisoning ? 
Unabsorbed poison is to he removed by wash- 
ing the stomach with infusion of tea containing 
powdered charcoal, or by emetics of zinc sulfate 
or of apomorphin. The patient is to be kept in 
motion to prevent sleep. Cold affusions. Artifi- 
cial respiration, continued so long as the heart’s 
action is perceptible. 
1043. Name the two most important alkaloids of 
cinchona hark. 
Quinin and cinclionin. 
1044. With what peculiar acid are they com- 
bined in nature ? 
Kinic acid. 
1045. State the physical properties of quinin. 
A light, white, amorphous powder, without 
odor, having a persistent, bitter taste and an 
alkaline reaction. Very sparingly soluble in 
water, readily soluble in alcohol, chloroform, 
and ether. It separates, on evaporation of its 
alcoholic or ethereal solution, in crystals contain- 
ing 3Aq. 
CINCHONA ALKALOIDS CHEMISTRY AND TOXICOLOGY. 
267 
1046. Explain the solubility of quinin in dilute 
H SO- 
The quinin combines with the acid to form 
the bisulfate, which is soluble. 
1047. What salt of quinium is commonly used 
in medicine, and what are its physical properties? 
The sulfate. It crystallizes in thin, light, 
white needles, with 7Aq; sparingly soluble in 
H20, readily in boiling alcohol and in ether. It 
dissolves readily in dilute H2S04, the soluble bi- 
sulfate being formed. Solutions of this salt, al- 
though they are colorless by transmitted light, 
present beautiful pale-blue reflections. 
1048. By what reactions may quinin be recog- 
nized ? 
1. By the blue reflections (fluorescence) of its 
solution in dilute H2S04. 2 When chlorin water 
and aqua ammoniae are added to quinin solution 
it assumes a green color. 3. A deep red color is 
produced in solutions of quinin when chlorin 
water, potassium ferrocyanid, and aqua ammo- 
nix are added in the order named. 
1049. How is quinin adulterated? 
With gypsum, stearic acid, starch, salicin, and 
cinchonium sulfate. 
1050. How may the presence of mineral sub- 
stances be detected ? 
By heating to redness; if any mineral matter 
be present it remains after heating, while pure 
quinin is entirely volatilized. 
1051. How is the presence of cinchonin detected? 
Place a gram of the sample in a test tube, add 
10-15 grams of ether and 2 grams of aqua am- 
moniae, shake, and allow the mixture to separate 268 
ESSENTIALS OP 
into two layers ; if cinchonin be present it will 
appear as a precipitate in the lower layer. 
1052. How may the other adulterations named 
be detected? 
Stearic acid may be detected by its insolubility 
in dilute II2S04; starch by its insolubility in 
boiling alcohol ; and salicin by the red color pro- 
duced upon the addition of H2S04. 
1053. What two important alkaloids belong to 
this class ? 
Strychnin and brucin. 
1054. Give the properties of strychnin. 
It crystallizes in small, transparent, four-sided 
prisms ; odorless, having an intensely bitter taste 
and an alkaline reaction ; very sparingly soluble 
in water, soluble in benzene, chloroform, and 
boiling dilute alcohol, insoluble in absolute alco- 
hol, ether, and solutions of the alkalies. It is a 
strong base, neutralizing acids and forming salts, 
most of which are crystalline, soluble in water, 
and very bitter. 
1055. Describe the tests for strychnin. 
1. The alkaloid forms a colorless solution with 
concentrated H2S04. If a crystal of potassium 
dichromate be drawn through this solution, it is 
followed by a track of color which is first (for 
an instant) blue, then violet, then rose-colored, 
and finally yellow. 2. The alkaloid and its salts 
are intensely and persistently bitter. 3. Injected 
into a lymph pouch of a frog, it causes violent 
tetanic spasms and opisthotonos. 
STRYCHNOS ALKALOIDS. CHEMISTRY AND TOXICOLOGY. 
269 
1056. Describe the prominent symptoms of 
strychnin poisoning. 
The action of the poison is usually rapid. The 
characteristic symptoms are tetanic spasms, with 
opisthotonos, sometimes emprostliotonos or pleu- 
rosthotonos. The pain is intense, and the patient 
suffers from thirst and is in apprehension of 
death. The spasms increase in frequency and in 
duration, and when death follows it is either dur- 
ing a spasm, by paralysis of the muscles of respi- 
ration, or in an interval, from exhaustion. 
1057. What treatment should be followed in 
poisoning by strychnin ? 
Unabsorbed poison is to be removed as directed 
in opium poisoning, and the convulsions are to 
be arrested or mitigated by bringing the patient 
under the influence of chloral or chloroform as 
rapidly as possible. The patient is to be kept as 
quiet as possible. 
1058. Give a test for brucin. 
Upon the addition of HN03 a bright red color 
is produced, which gradually turns to yellow on 
the addition of stannous chlorid, or to reddish- 
violet on the addition of ammonium sulfhy- 
drate. 
1059. What are ptoma'ins, leucomai'ns, and 
toxins ? 
They are alkaloids of animal origin. The 
ptoma’ins are products of the putrefaction of 
dead animal tissues or fluids. The leucomains 
are normal products of the living body. The 
toxins are actively poisonous animal alkaloids, 
either the products of pathogenic bacteria or 
ptoma'ins or leucomains, 270 
ESSENTIALS OP 
1060. Name and state the origin of some of the 
best-known toxins. 
Typhotoxin, from the cultures of the Kocli- 
Eberth typhoid bacillus ; Tetanin, from the cul- 
tures of a bacillus from wounds causing tetanus ; 
Mytilitoxin, from poisonous mussels; Mydale'in, 
a putrid product; Mydatoxin, from the cultures 
of the comma bacillus. Unnamed toxins also 
exist in normal urine. 
(See Q. 856-863, and Manual, pp. 470-472.) 
(For Indigo and related substances see Manual, 
pp. 450-452.) 
1060a. How is oil of turpentine obtained ? 
A resinous juice, exuded from incisions in 
certain varieties of pine, and known as crude 
turpentine, is distilled with water; the volatile 
spirit or oil of turpentine passes over, while rosin 
remains in the still. 
1061. State the prominent properties of oil of 
turpentine. 
A colorless liquid, having a characteristic odor ; 
lighter than water ; boiling at 156° (312°.8 F.); 
readily inflammable, burning with a smoky 
flame ; a solvent for phosphorus, sulfur, india- 
rubber, and many resins. When exposed to the 
air it assumes a yellow tinge, becomes thicker, 
and absorbs oxygen. 
1061a. Describe the prominent properties of 
caoutchouc. 
It is a soft, flexible, yellowish semi-solid ; in- 
soluble in water and in alcohol, not acted upon 
TEREBENTHIN SERIES. CHEMISTRY AND TOXICOLOGY. 
271 
by dilute acids. It lias the property of combin- 
ing with sulfur to produce “ vulcanized rubber,” 
a very elastic and impermeable material ; and 
“ebonite,” or “hard rubber,” a somewhat flex- 
ible, although brittle, solid, valuable as an in- 
sulating medium. 
1062. Describe the 'prominent properties of gutta- 
percha. 
It is a tough, flexible, but inelastic substance. 
A good insulating medium, for which purpose it 
is principally used. It dissolves in chloroform. 
1063. What varieties of camphor occur in com- 
merce ? 
Borneo camphor, or Borneol, and Chinese, or 
Japanese, camphor. The latter contains two 
atoms of hydrogen less than the former. 
1064. State the more prominent properties of 
Japanese camphor. 
White, semi-transparent crystals, having a 
strong, aromatic odor and a sharp, bitter taste ; 
very volatile ; sparingly soluble in water, readily 
soluble in alcohol, ether, and the oils. 272 
ESSENTIALS OF 
SUBSTANCES WHOSE CONSTITU- 
TION IS UNKNOWN. 
GLUCOSIDS. 
1065. What is the characteristic property of the 
glucosids ? 
That of splitting up, under the influence of the 
acids, alkalies, and of certain ferments, into a 
sugar (usually glucose) and some other substance. 
1066. Mention some of the more important glu- 
cosids, and the sources from which they are ob- 
tained. 
Amygdalin from bitter almonds; digitalin, 
digitonin, digitalein, and digitoxin from digi- 
talis ; jalapin from scammony ; convolvulin from 
jalap ; salicin from willow bark ; santonin from 
artemisia ; solanin from dulcamara. 
1067. Describe the prominent symptoms of poi- 
soning by digitalis. 
Nausea, and occasionally vomiting. Some- 
times colic and diarrhoea. After two or three 
hours, marked diminution in the freopiency of 
the pulse, which may fall to 40 or even 25. 
Dyspiuea, attended by a sense of oppression in 
the chest and coldness of the extremities. Head- 
ache, vertigo, and tendency to sleep. Usually 
attacks of syncope occur, provoked sometimes by 
the slightest movement of the patient. Death is CHEMISTRY AND TOXICOLOGY. 
273 
generally by syncope, sometimes after several 
hours of coma succeeded by convulsions. 
1068. What treatment should be adopted in poi- 
soning by digitalis ? 
The patient must be kept strictly in the recum- 
bent position. The stomach should be washed 
out with infusion of tea by the stomach pump or 
siphon. Stimulants should be given. 
1069. What are the tannins or tannic acids ? 
Substances of different composition existing in 
various barks, leaves, etc. They are amorphous 
bodies, having a faintly acid reaction, soluble in 
HjO, and astringent. They all precipitate with 
albumen, the alkaloids, and the ferric salts; and 
they also form imputrescible compounds with al- 
buminoid and gelatinoid substances. They exist 
notably in oak bark, gall nuts, cinchona, coffee. 
They are, with one possible exception, glucosids. 
1070. Whence is the Acidum tannicum, U. S. 
P., obtained, and what are its chemical name and 
■formula ? 
From nutgalls, which are excrescences pro- 
duced upon the oak by the puncture of an in- 
sect. It is known as gallotannic acid. It has 
the formula CuHioOo, and is considered as being 
formed by the union of two molecules of gallic 
acid, with loss of a molecule of water : 
2CtH,0. = HaO + C14H10O9 
Gallic acid. 
Water. 
Gallotarmic 
acid. 
1071. Give the prominent properties of gallotan- 
nic acid. 
A light yellowish, amorphous powder, highly 
18 274 
ESSENTIALS OF 
astringent. Readily soluble in HaO, less so in 
alcohol, insoluble in ether. It has acid proper- 
ties, and forms salts which are amorphous. 
1072. What class of medicinal substances con- 
tain tannin? 
The vegetable astringents. 
1073. Why are the alkaloids and tartar emetic 
incompatible with tannic acid ? 
Because insoluble tannates are formed. 
1074. W[hat is formed when tannic acid and a 
ferric compound are brought together ? 
Black ink. 
ALBUMINOID SUBSTANCES 
1075. State the general properties of albuminoid 
substances. 
They are nitrogenized bodies, for the most part 
incapable of crystallization, having, when dry, 
the appearance of gum arabic, odorless, insipid, 
insoluble in ether and alcohol. Their solubility 
in water varies according to the temperature and 
the presence or absence of alkalies, acids, and 
mineral salts. They enter very readily into the 
series of changes designated by the term putre- 
faction. They are all the products of organized 
bodies, to whose life they are indispensable. 
1076. What is understood by coagulation ? 
The property of many albuminoid substances 
of being converted into insoluble modifications by 
the action of heat, mineral acids, alcohol, and 
certain metallic salts. When once converted into 
PROTEID BODIES. CHEMISTRY AND TOXICOLOGY. 
275 
these modifications, the albuminoids will not 
return to their primitive form. 
i (For composition and products of decomposi- 
febn of albuminoids, see Manual, pp. 472-475.) 
U.077. What is putrefaction 
It is decomposition of dead albuminoid matter 
under the influence and as a result of the processes 
of nutrition of certain bacteria, and attended by 
the evolution of more or less fetid products. 
1078. What conditions are necessary to putre- 
faction ? 
The presence of albuminoid matter, bacteria, 
air and water, and a temperature between 5° and 
90° (41°-194° F.). 
1079. Explain the distinctions between the terms 
germicide, antiseptic, disinfectant, deodorant. 
Germicides are substances or agents which de- 
stroy bacteria and their germs—eg., mercuric 
clilorid and heat. Antiseptics are substances 
which prevent or restrain putrefaction. They are 
either germicides, which act by destroying the 
bacteria causing putrefaction, or agents which, 
without destroying the vitality of these organ- 
isms, render the conditions unfavorable for their 
development. Thus cold and the aluminium 
salts are antiseptic but not germicidal. Disinfec- 
tants are substances or agents which restrain 
infectious diseases by destroying or removing 
their specific poisons. Some disinfectants are 
germicides, as chlorin; others act by dilution or 
removal without being germicides, as soap and 
water and fresh air. Deodorants are substances 
which destroy the odorous products of putrefac- 
tion. Thus one of the actions of SOa is to destroy 
P,S. 276 
ESSENTIALS OF 
1080. Name some of the products of putrefac- 
tion. 
The products of putrefaction vary with the 
conditions. The most prominent are : (1) Inor- 
ganic products, such as N, H, H2S, JNH3; and 
simple organic compounds, such as C02 and hy- 
drocarbons. (2) Acids of the acetic series in great 
abundance, and acids of the oxalic and lactic 
series. (3) Non-aromatic monamins and diamins, 
among which are included some of the ptomains 
(see Q. 770-775 ; 856-859). (4) Aromatic pro- 
ducts, among which are phenols, phenylic deri- 
vatives, indol, scatol, pyridin derivatives, and 
some of the ptomains. 
1081. What is adipocere? 
A substance resembling tallow, and consisting 
chiefly of palmitate, stearate, and oleate of am- 
monium, with an undetermined albuminoid body 
and mineral salts. It is produced by a modified 
putrefaction. 
1082. Oive “ color reactions” for albuminoid 
substances. 
1. They are dissolved by boiling concentrated 
HC1, the solution being violet-red in color. 2. 
They turn yellow with concentrated HN03, the 
color changing to orange on addition of NH«HO. 
3. A solution of an albuminoid in excess of glacial 
acetic acid is colored violet and rendered faintly 
fluorescent by concentrated H2S04. 4. Solution 
of mercuric nitrate with excess of nitric acid (Mil- 
Ion’s reagent) gives a fine red color when warmed 
with an albuminous substance. 5. With Pet- 
tenkofer’s reaction the same result is obtained 
as with the biliary salts. CHEMISTKY AND TOXICOLOGY. 
277 
(For other tests see Q. 1088-1091, and Manual, 
pp. 475, 476. For classification see Manual, pp. 
476, 477.) 
1083. Wherein do albumens and globulins differ 
from each other ? 
The albumens are soluble in pure water; the 
globulins are insoluble in pure water, but dissolve 
in dilute solutions of neutral salts (NaCl, KC1, 
MgS04, etc.). Both are coagulated by heat. 
1084. Describe the composition of egg albumen. 
It consists of two globulins and three albumens, 
all coagulable by heat, but at different tempera- 
tures ranging from 57°.5 (135°.5 F.) to 82° 
(179°.6 F.), and peptones (see Q. 1098-1102), 
which last increase in quantity as the egg be- 
comes stale. 
1085. Where does serum albumen exist in the 
animal body ? 
In the blood serum, lymph, chyle, pericardial 
fluid, the fluids of cysts and transudations, and 
pathologically in the urine. Human serum albu- 
men consists of three distinct proteids coagulating 
at 73° (163°.4 F.), 77° (170°.6 F.), and 84° (183°.2 
F.)- 
1086. How is the sp. gr. of the urine affected by 
the presence of serum albumen ? 
It is lowered. 
1087. Why should the urine be tested for albu- 
men before examining for sugar f 
Because albumen interferes with the tests for 
sugar. If present, it must therefore be removed 
before examining for sugar. (See Q. 938.) 
1088. How is urine tested for albumen ? 
By the action of heat and of nitric acid; both 278 
ESSENTIALS OF 
tests must be used, as neither is of itself conclu- 
sive. 
1089. Describe the heat test. 
The reaction is first observed. If it be acid, 
the urine is simply heated to near the boiling 
point. If the urine be neutral or alkaline, it is 
rendered faintly acid by the addition of dilute 
acetic acid, and heated. If albumen be present, 
a coagulum is formed, varying in quantity from a 
faint cloudiness to entirS solidification, according 
to the quantity of albumen present. The coagu- 
lum is not redissolved upon the addition of HN03. 
1090. What are the sources of error to be avoided ? 
Albumen is soluble in alkaline liquids. The 
urine is therefore rendered acid, to prevent small 
quantities of albumen remaining in solution upon 
the application of heat, and thus escaping detec- 
tion. Albumen is also slightly soluble in dilute 
HN03, therefore acetic acid is used. It is also 
soluble in a large amount of acetic acid, therefore 
the addition of acetic acid should be limited to 
the amount necessary to produce an acid reaction. 
A urine rich in earthy phosphates deposits, on 
boiling, a precipitate closely resembling that of 
coagulated albumen, therefore HN03 is added 
after heating. It dissolves the phosphates, but 
does not affect the albumen. Nitric acid cannot 
be used alone as a test for albumen, because if 
the urine contain an excess of urates, these are 
decomposed upon the addition of acid, and the 
almost insoluble uric acid is precipitated, and 
might easily be mistaken for albumen. 
1091. Describe Heller's modification of the nitric 
acid test. 
Place in a test tube a layer of IIN03 about 2 CHEMISTRY AND TOXICOLOGY. 
279 
centim. in thickness ; then, with a pipette, care- 
fully float upon the surface of this a layer of the 
urine in such a manner that the liquids do not 
mix. If albumen be present, a cloudy ring ap- 
pears at the point of junction of the two layers, 
the borders of the cloud being sharply defined. 
A cloudy ring may be formed by the presence of 
an excess of urates, but in this case it is not at, 
but above the point of junction of the layers, and 
its upper border is not sharply defined, but fades 
off gradually. 
1092. Give a process for determining the quan- 
tity of albumen in urine. 
Heat a known volume of acid urine to near 
the boiling point; collect the coagula upon a 
weighed filter, wash with water; dry the filter 
with adhering albumen at 100° (212° F.); weigh. 
The difference between the two weighings indi- 
cates the quantity of dry albumen in the volume 
of urine used. [Some authors direct to weigh 
the filter and albumen wet; when this is done 
there is no approach to accuracy, as it is im- 
possible to judge how much water is being 
weighed.] 
1093. Why should albuminous urine always be 
examined microscopically ? 
To determine the presence or absence of blood 
or pus corpuscles, spermatozoa, and casts. When 
the urine contains blood, pus, or spermatic fluid, 
it is always slightly albuminous. The presence 
of albumen has then no clinical importance be- 
yond that attaching to the fluids named Casts 
are never present in the urine of persons free 
from organic disease of the kidneys. 280 
ESSENTIALS OP 
1094. Give the names and sources of some of the 
more important globulins. 
Vitelin exists in the yolk of eggs and in the 
crystalline lens. Myosin is one of the principal 
constituents of muscular fibre in rigor mortis. 
Paraglobulin exists in blood serum, pericardial 
fluid, hydrocele fluid, lymph and chyle, and, ac- 
companying serum albumen, in albuminous urine. 
It is precipitated from dilute solution by C02, or 
by dissolving magnesium sulfate in the solution 
to saturation. Paraglobulin may be separated 
from serum albumen by MgS04. Fibrinogen oc- 
curs in blood plasma, and yields fibrin during 
coagulation of blood. 
1095. State the characters of fibrin. 
White, elastic filaments interlaced in all direc- 
tions, insoluble in water. When treated with 
dilute acids, it swells and gradually dissolves, al- 
though usually incompletely. 
1096. Describe the alkali-albumens and acid- 
albumens. 
Alkali-albumen is precipitated in white flocks 
by the addition of acetic acid to an aqueous solu- 
tion of the jelly-like product obtained by the 
action of a caustic alkali upon an albumen. 
Their solutions are acid in reaction, and are only 
coagulated at a temperature somewhat above 
100” (212° F.). The acid-albumens, or syntonins, 
are white, gelatinous substances produced by the 
action of dilute acids upon albuminoids. They 
are soluble in very dilute HC1 and in alkaline so- 
lutions, and are precipitated by neutral salts but 
not by heat. CHEMISTRY AND TOXICOLOGY. 
281 
1097. Describe the albumoses or propeptones. 
They are products produced during peptic or 
pancreatic digestion of albuminoids, intermedi- 
ate between acid-albumens and peptones. They 
differ from the peptones in being precipitated by 
acetic acid, by many metallic salts, NaCI and 
HN03; and from the albumens in the property of 
their precipitates of dissolving on the application 
of heat and reappearing on cooling. Albumoses 
are produced by the action of natural or artificial 
gastric juice on fibrin, egg and serum albumen, 
the globulins, and casein. 
1098. Into what substance are all the albuminous 
bodies converted by the action of the gastric juice ? 
Into albuminose or peptone. 
1099. By what constituents of the gastric juice is 
this change brought about f 
By the combined action of the free acid and a 
substance, known as pepsin, peculiar to the gas- 
tric juice. Neither pepsin nor an acid will pro- 
duce the change alone. 
1100. By what agency, other than pepsin, are 
albuminous substances converted into albuminose 
during digestion ? 
By the action of trypsin, a constituent of the 
pancreatic secretion, which effects the same 
transformation, but by a different method, and 
in an alkaline reaction. 
1101. In what important point does albuminose 
differ from other albuminous substances? 
In being capable of dialysis—i.e., passing 
through animal membranes, which other albu- 
minous substances are incapable of. It is in the 
form of albuminose that the food elements of this 
class pass from the intestine into the blood. 282 
ESSENTIALS OE 
1102. By what test may peptone be distin- 
guished from other albuminoids? 
By the “ biuret test ” : Add a mere trace of 
CuS04 solution, and then KHO or NaHO solu- 
tion, and warm ; a purple or reddish-violet color 
is produced. 
1103. What is pep toxin ? 
Peptone is one of the earliest products of pu- 
trefaction, and under these conditions is accom- 
panied by peptoxin, a crystallizable and actively 
poisonous substance. 
1104. By what names is the coloring matter of 
the Mood known ? 
Haemoglobin, haematocrystallin, and cruorin ; 
the first is the name now in general use. 
1105. In what portion of the blood does it exist ? 
In the corpuscles. 
1106. What are its physical properties ? 
It is, when pure, a crystalline solid, more or 
less soluble in water, soluble in dilute alcohol 
and in dilute solutions of the alkalies; red or 
purple in color. It dialyzes very slowly, al- 
though it crystallizes with more or less facility. 
1107. How does haemoglobin from the blood of dif- 
ferent kinds of animals differ in physical proper- 
ties ? 
In the facility with which it forms crystals and 
in the forms of the crystals. In its solubility. 
The crystals from the blood of the ox are very 
readily soluble in water, while those from the 
blood of the raven are almost insoluble in that 
fluid. 
1108. Of what elements is haemoglobin composed ? 
C, H, N, O, S, and Fe. CIIEMISTRY AND TOXICOLOGY. 
283 
1109. Explain the change which haemoglobin un- 
dergoes in passing through the lungs. 
Haemoglobin exists in the blood in two condi- 
tions of oxidation, which are designated by the 
names oxyhaemoglobin and reduced haemoglobin. 
The latter contains the less quantity of oxygen, 
and preponderates in venous blood. As the 
blood circulates in the lung, its haemoglobin takes 
up oxygen from the air, in the air vesicles, to 
form oxyhaemoglobin, in which the oxygen is 
held in an easily decomposable chemical com- 
bination. 
1110. What changes does oxyhaemoglobin under- 
go in the capillary circulation, and what is its 
function ? 
The opposite change occurs to that which takes 
place in the pulmonary circulation. The oxy- 
haemoglobin is decomposed ; oxygen passes into 
the tissues, and reduced haemoglobin returns by 
the venous system to the lungs to receive a fresh 
supply of oxygen. The coloring matter is, there- 
fore, the carrier of oxygen from the air to the 
tissues. 
1111. How may the two conditions of haemoglobin 
be distinguished by the spectroscope ? 
Solutions of oxyhaemoglobin present two ab- 
sorption bands, between the solar lines D and 
E. That nearer D being narrower, sharper, and 
darker than that nearer E. Solutions of reduced 
haemoglobin, on the other hand, show a single 
broad band, occupying about the space left 
bright between the oxyhaemoglobin bands, and 
more faint and ill-defined than either of those. 284 
ESSENTIALS OP 
1112. What action has carbon monoxid on oxy- 
hemoglobin f 
It drives out all of the oxygen, and forms, with 
the reduced haemoglobin, a compound which is 
more stable than oxyhaemoglobin, and from which 
the carbon monoxid cannot be again displaced by 
oxygen. 
1118. What is heematin ? 
An uncrystallizable coloring matter formed by 
the decomposition of haemoglobin. 
1114. Row may hamwgloMn be detected in the 
unne ? 
1. By spectroscopic examination (see Q. 1110). 
2. To a few drops of the urine in a test tube add 
a drop of a freshly prepared tincture of guaiacum 
and a little ozonic ether (or turpentine), and 
shake; a blue color is produced. 
1115. What peculiar albuminoid substance exists 
in milk, and what are its properties ? 
Casein. An amorphous, white substance, taste- 
less and odorless, very soluble in alkaline fluids. 
Coagulates with acids, and under the influence of 
infusion of rennet (mucous membrane of fourth 
stomach of calf), but not by heat. 
1116. Whence is gelatin obtained, and how ? 
From bones, tendons, fish bladders, skins, etc. 
These tissues contain a peculiar substance, called 
collagen, in combination with mineral and other 
matters. When collagen is heated with water, 
under such pressure that the temperature reaches 
106° (222°.8 F.), a solution is formed which, on 
cooling, solidifies to a jelly. This jelly contains 
a new substance, gelatin, glue, isinglass, or size, 
according to the substances used and the peculi- 
arities of the manufacturing process followed. CHEMISTRY AND TOXICOLOGY. 
285 
1117. What are the toxalbumens? 
Substances of albuminoid nature and possessed 
of poisonous qualities. A few are of vegetable 
origin, as abrin, the poisonous constituent of 
jequirity, but most are products of bacterial ac- 
tion, pathogenic or putrefactive. 
(See Manual, pp. 477-489.) 
ANIMAL CRYPTOLYTES, OR FERMENTS. 
1118. What are the characters of substances of 
this class ? 
They are nitrogenized bodies, in some respects 
resembling the albuminoids, which have the 
power to provoke changes in other organic sub- 
stances in some way as yet imperfectly under- 
stood. 
1119. What cryptolyte exists in the saliva, and 
what is its action ? 
Ptyalin. It has the property of changing 
starch into sugar in a liquid of alkaline reaction. 
1120. What cryptolyte exists in the gastric juice, 
and what is its principal action? 
Pepsin. In the presence of a free acid (best 
HC1) it converts albuminous substances into 
albuminose. 
1121. What cryptolytes exist in the pancreatic 
secretion, and what are their actions ? 
1. Trypsin, which converts albuminous sub- 
stances into albuminose in alkaline liquids. 2. A 
diastatic cryptolyte, converting starch into malt- 
ose and glucose. 3. Some substance capable of 
emulsifying and saponifying the fats, 286 
ESSENTIALS OF 
ANIMAL COLORING MATTERS. 
(For blood-coloring matter see Q. 1104-1114.) 
1123. Name the principal coloring matters of the 
bile. 
Bilirubin and biliverdin. 
1123. State the properties of bilirubin. 
It forms microscopic, orange or brick-red crys- 
tals, soluble in chloroform or benzene, insoluble 
in water, ether, alcohol, and dilute acid, soluble 
in dilute alkalies. When acted upon by oxidiz- 
ing agents, it is converted into biliverdin. 
f 1124. Describe Gmelin's reaction for bile pig-\ 
fments as applied to the urine. ' 
Put 3 c.c. HNOs in a test tube, add a piece of 
wood, and heat until the acid is yellow ; cool. 
When cold, float some of the urine to be tested 
upon the surface of the acid. A green band is 
formed at the junction of the liquids, which 
gradually rises, and is succeeded from below by 
blue, reddish-violet, and yellow. 
1125. How should urine be examined for color? 
It should be acidulated with HC1, and allowed 
to stand for four hours, after which it should be 
placed in a beaker of about three inches diame- 
ter, and the color observed by transmitted light. 
1126. Describe how the color may vary physio- 
logically. 
The greater the quantity of urine voided, the 
lighter the color, as a rule. The morning urine 
is darker than that voided at other times. The 
use of animal food also produces a high colored 
urine. The use of certain drugs communicates 
peculiar colors to the urine ; rhubarb, bright yel- CHEMISTRY AND TOXICOLOGY. 
287 
low ; senna, brownish ; logwood, reddish ; san- 
tonin, orange-red or golden-yellow. 
1127. Under what pathological conditions is the 
urine pale ? 
Under those conditions which produce an in- 
crease in the quantity, and in anaemia. In the 
latter condition the quantity is not increased. 
1128. Under what conditions is it high-colored? 
Under those conditions in which the quantity 
of water eliminated by the kidneys is diminished, 
while the elimination of the solids remains nor- 
mal or is increased. Such urines have a high 
specific gravity, and are strongly acid. As the 
coloring matter of the urine is a product of the 
disassimilation of haemoglobin, an absolute in- 
crease in the quantity of urine pigment elimi- 
nated indicates an increased destruction of blood 
corpuscles. 
Note.—A comparatively light-colored urine is frequent- 
ly found, on addition of acid, to contain a large quantity 
of coloring matter, which, before the action of the acid, 
was in the form of a colorless combination. 
1129. To what do broicn and black urines owe 
their color ? 
To the presence of abnormal coloring matters, 
blood, or bile. APPENDIX. 
ELEMENTS. 
A. 
Aluminium A1 ‘>7 
An t i mony S b ‘ " \ ao 
Arsenic As 749 
Barium ........ Ro 1 qa q 
Bismuth IK 
Boron B YY 
Bromin... 80 
Cadmium Cd 111.8 
Caesium Cs 132.6 
Calcium Ca 49 
(arbon q jo 
Chlorin C1 35 5 
Cnromium O ko a 
Columbium.... Cb 94 
Copper Cu 63 2 
Bavymm Da 154' 
Didymium .• D 144 8 
Erbium E . 165 9 
Fluorin p jg 
Gallium Ga*;;: ess 
Germanium Gr ... 72 3 
Glucinum Gl..:I]" g' 
196.2 
indium "'.in' 113 4 
Indm I 126.9 
Indium Ir 193 7 290 
APPENDIX. 
Iron Fe 55.9 
Lanthanium La 188.5 
Lead Pb 206.9 
Lithium Li 7 
Magnesium Mg. 24 
Manganese Mn'. 54 
Mercury —Hg 199.7 
Molybdenum Mo 95.5 
Nickel.. Ni 58 
Nitrogen N 14 
Osmium Os 198.5 
Oxygen O 16 
Palladium Pd 105.7 
Phosphorus P 31 
Platinum Pt 194.4 
Potassium K 39.1 
Rhodium Rh 104.1 
Rubidium Rb 85.3 
Ruthenium Ru 104.2 
Samarium Sm 150 
Scandium Sc 44 
Selenium Se 78.9 
Silicon ... Si 28 
Silver Ag 107.7 
Sodium Na 23 
Strontium Sr 87.4 
Sulfur., S 32 
Tantalum Ta 182 
Tellurium Te 128 
Thallium T1 203.7 
Thorium Th 233 
Tin Sn 117.7 
Titanium Ti .... 49.9 
Tungsten...- W... , 183.6 
Uranium U 238.5 
Vanadium V 51.8 
Ytterbium Yb 172.7 
Yttrium Y 898 
Zinc Zn 64.9 
Zirconium Zr 89.6 APPENDIX. 
291 
K. 
MEASURES AND WEIGHTS. 
I. 
1 Kilometre = 1000 metres. 
1 Hectometre = 100 “ 
1 Decametre = 10 “ 
Measures of length. 
1 Millimetre = 0.001 metre 
1 Centimetre = 0 01 “ 
1 Decimetre =0.1 “ 
1 Kilometre = 0.6214 mile. 
1 Metre = 3.2809 feet. 
1 Metre = Unity. 
1 Centimetre = 0.3937 inch. 
1 Millimetre = 0.0394 “ 
1 Foot — 30.48 centimetres. | 1 inch = 2.54 centimetres. 
1 Kilogram —1000 grams. 
1 Hectogram100 “ 
1 Decagram = 10 “ 
Weights. 
1 Milligram • — 0.001 gram. 
1 Centigram *= 0.01 “ 
1 Decigram = 0.1 “ 
1 Kilogram=2.679 lbs. Troy. 
1 Gram. 
1 Gram. — 15.434 grains. 
1 Grain = 0.065 gram. 
1 Scruple *= 1.296 grams. 
1 Pound = 373.19 grams. 
11 Dram — 3.888 grams. 
11 Ounce — 31.103 “ 
Measures of volume. 
1 Cubic metre — 1000 litres. 
1 Cubic centimetre = 0.001 litre. 
1 Litre = 1 cubic decimetre. 
1 Litre ■= 1.0567 quarts. 
1 Minim = 0 0614 c.c. 
1 Fluid dram — 3.689 “ 
1 c.c = 0.061 cubic inch. 
1 Fluid ounce — 29.513 c.c. 
1 Pint - 472.208 “ APPENDIX. 
To convert thermometric scales. 
Centigrade into Fahrenheit: 
CeDt- x 9 + 32 — Fah. 
5 
Fahrenheit into Centigrade; 
Ffth-- 32 x 5 Cent. INDEX 
Acetanilid, 256 
Acetylene, 234 
series, 177, 234 
Acid, 9 
acetic, 190 
amidoacetic, 198 
amidocaproic, 199 
arsenic, 82 
arsenious, 81 
benzoic, 252, 253 
boric, 95 
butyric, 191 
carbazotic, 251 
carbolic, 249 
carbonic, 208, 213 
cholic, 199 
chromic, 102 
citric, 236 
crotonic, 206 
cyanic, 204 
dichromic, 102 
gallic, 254 
gallotannic, 273 
glycocholic, 199 
A 294 
INDEX. 
Acid, hippuric, 253 
liydrazoic, 61 
liydriodic, 47 
hydrochloric, 38, 40 
hydrocyanic, 201, 253 
hydrofluoric, 36 
hypophosphorous, 75 
lactic, 213 
malic, 228 
meconic, 263, 265 
metaphosphoric, 75 
muriatic, 40 
nitric, 64 
nitroliydrocliloric, 41 
nitromuriatic, 41 
oleic, 206 
oxalic, 215 
phenic, 249 * 
phosphoric, 75 
phosphorous, 74 
picric, 251 
prussic, 201 
pyrophosphoric, 75 
salicylic, 253 
silicic, 98 
sulfovinic, 188 
sulfuric, 55 
sulfurous, 53, 54, 55 
tannic, 273 
tartaric, 234 
taurocholic, 199 
thioarsenious, 83 
thiocyanic, 205 
trichromic, 102 INDEX. 
295 
Acid, uric, 224 
valerianic, 192 
Acids, acrylic, 205 
amido, 198 
carbamic, 219 
monobasic, 189 
Adenin, 226 
Adipocere, 276 
Air, 60 
Albumen, 277 
Albuminose, 281 
Albuminoid substances, 274 
Albumoses, 281 ‘ 
Alcohol, 181, 183 
amylic, 186 
benzoic, 252 
ethylic, 183, 184 
methylic, 183 
Alcohols, 181, 228 
diatomic, 207 
monoatomic, 181 
primary, 182 
secondary, 182 
tertiary, 182 
triatomic, 227 
Aldehyde, 182, 194 
acetic, 194 
benzoic, 252 
Alkaloids, 218, 261 
Allotropy, 67 
Alum, 109 
Aluminium, 108 
Amalgam, 161 
Amanitin, 198 296 
INDEX. 
Amido acids, 198 
compounds, 200 
Amids, 196 
Amins, 196 
Ammonia, 61 
Ammonium, 140 
chlorid, 142 
sulfhydrate, 141 
Amygdalin, 272 
Amyl kydroxid, 186 
Analysis, 3, 27 
Anhydrid, 23 
arseuious, 78 
carbonic, 209, 210 
chromic, 102 
phosphoric, 74 
phosphorous, 74 
silicic, 98 
sulfuric, 55 
sulfurous, 53 
tliiocarbonic, 213 
Anhydrous, 27 
Anilin, 255 
Antifebrin, 256 
Antimony, 93 
butter of, 94 
oxid of. 94 
pentasulfid, 94 
trichlorid, 94 
trisulfid, 93 
Anti pyrin, 259 
Antiseptics, 275 
Apomorphin, 265 
Aqua fortis, 64 INDEX. 
297 
Aqua regia, 41 
Aromatic substances, 245 
Arsenic, 76 
disulfid, 82 
flowers of, 79 
pentasulfid, 83 
pentoxid, 82 
trioxid, 78 
trisulfid, 83 
white, 78 
Artiads, 7 
Atom, 2 
Atomic weight, 6 
Atropin, 257, 258 
Azo compounds, 200 
Azo-paraffins, 200 
B 
Barium, 144, 150 
Base, 10 
Basicity, 9, 190 
Benzene, 245, 247 
Bile acids, 198 
pigments, 286 
Biliary salts, 199 
Bismuth, 117 
nitrate, 117 
subnitrate, 118 
Bismuthyl, 118 
Bleaching powder, 146 
Blue vitriol, 158 
Bone black, 147 
Borax, 129 298 
INDEX. 
Boron, 95 
Bromin, 45 . 
Bromoform, 181 
Brucin, 268 
c 
Cadaverin, 218 
Cadmium, 151 
Caesium, 128 
Caffein, 227 
Calcium, 144 
carbonate, 149 
clilorid, 145 
hydroxid, 145] 
hypochlorite, 146 
monoxid, 144 
oxalate, 150 
phosphates, 147 
sulfate, 146 
Calculi, 149, 150, 152, 226 
Calomel, 168 
Camphor, 271 
Caoutchouc, 270 
Carbamid, 220 
Carbimid, 220 
Carbohydrates, 236 
Carbon, 96 
compounds, 97, 171 
dioxid, 210, 212 
disulfid, 213 
monoxid, 209 
Carbonates, 213 
Casein, 284 INDEX. 
299 
Cellulose, 243 
Cerebrin, 233 
Chalk, 149 
Chemistry, 1 
Chloral, 194 
Chlorin, 37 
oxygen compounds of, 45 
Chloroform, 180 
Cholesterids, 260 
Cholesterin, 260 
Cholin, 197 
Chrome yellow, 103, 114 
Chromium, 102 
Cinchonin, 266 
Classification of elements, 16 
Coagulation, 274 
Coal, 96 
Coca'fn, 257 
Coke, 97 
Combustion, 21, 22 
Composition, 12, 173 
Compounds, 2, 3, 12 
Conii'n, 252 
Constitution, 12, 173 
Copper, 156, 157 
oxids, 158 
sulfate, 158 
Corrosives, 42 
Corrosive sublimate, 165 
Creatin, 219 
Creatinin, 219 
Cryptolytes, 285 
Cyanogen, 201 300 
INDEX. 
D 
Deliquescence, 27 
Deodorizers, 275 
Deoxidation, 20 
Dextrin, 243, 244 
Diamids, 219 
Diamins, 217 
Diamond, 96 
Diastase, 183, 237, 243 
Digitalin, 272 
Disinfectants, 275 
E 
Efflorescence, 27 
Elements, 2, 289 
acidulous, 16, 35 
amphoteric, 16, 99 
basylous, 17, 123 
classification, 16 
typical, 16, 18 
Emulsion, 231 
Epsom salt, 152 
Equations, 8 
Ether, 187 
ethylic, 187 
nitrous, 193 
sulfuric, 187, 193 
Ethers, compound, 187, 192 
mixed, 187 
simple, 187 
Ethyl hydroxid, 183 
oxid, 187 
Ethylene, 207 INDEX. 
301 
Fats, 230 
Fermentation, 184 
Fibrin, 280 
Fibrinogen, 280 
Fluorin, 36 
Formulae, 8 
empirical, 173 
general, 172 
graphic, 175 
typical, 175 
Function, 176 
Fusel oil, 186 
F 
Galena, 111 
Gallium, 108 
Gelatin, 284 
Germicides, 275 
Globulins, 277, 280 
Glucinium, 108 
Glucose, 237 
Glucosids, 272 
Glycerids, 229 
Glycerol, 227 
Glycocol, 198 
Glycogen, 244 
Glycols, 207 
Gold, 99 
Graphite, 96 
Guanidin, 218 
Gun-cotton, 243 
Gutta-percha, 271 
Gypsum, 146 
G 302 
INDEX. 
Hsematin, 284 
Haemoglobin, 282 
Halogens, 35 
Homology, 172 
Hydracids, 9 
Hjferates, 29 
Hydrazin, 61 
Hydrocarbons, 176, 207, 284, 245, 261, 270 
Hydrogen, 18, 28 
antimonid, 93 
arsenid, 77 
dioxid, 34 
phosphids, 73 
sulfid, 50 
Hydroxids, 29 » 
Hydroxyl, 29 
Hydroxylamin, 61 
Hypoxantbin, 226 
H 
I 
Imids, 219 
Indium, 108 
Iodin, 46 
Iodoform, 181 
Iodol, 259 
Iron, 104 
cblorids, 105 
oxids, 104 
reduced, 104 
rust, 104 
sulfates, 106 INDEX. 
303 
Iron, sulfid, 105 
Isomerism, 172 
J 
Javelle water, 137 
K 
Kermes mineral, 94 
King’s yellow, 83 
L 
Lanolin, 260 
Laughing gas, 62 
Law of Ampere, 5 
of Avogadro, 5 
of definite proportions, 2 
of Gay Lussac, 4 
of multiple proportions, 3 
of reciprocal proportions, 4 
Lead, 111 
acetates, 114 
carbonates, 114 
chromate, 103, 114 
dioxid, 112 
iodid, 114 
monoxid, 112 
nitrate, 113 
peroxid, 112 
sulfid, 111 
Lecithins, 233 
Leucin, 199 304 
INDEX. 
Leucomains, 218, 269 
Lime, 144 
clilorid of, 146 
slaked, 145 
stone, 144, 149 
superphosphate, 148 
water, 145 
Litharge, 112 
Lithium, 123, 124, 225 
M 
Magnesia, 151 
Magnesium, 151 
oxid, 151 
sulfate, 152 
Malt, 183 
Manganese, 103 
dioxid, 103 
Marble, 149 
Marsh gas, 178 
Massicot, 112 
Measures, 291 
Mercury, 156, 160 
clilorids, 163 
iodids, 166 
oxids, 162 
sulfid, 167 
Metallocyanids, 205 
Metals, 10, 99 
Metamerism, 173 
Methyl, 178 
guanidin, 218 
hydrid, 178 INDEX. 
Methyl liydroxid, 183 
Mixtures, 4 
Molecular weight, 6 
Molecule, 2 
Monamins, 196 
Morphin, 264 
Murexid, 225 
Muscarin, 198 
N 
Nascent state, 40 
Neurin, 198 
Nicotin, 262 
Nitre, 136 
Nitrils, 200, 204 
Nitro compounds, 200 
Nitrobenzol, 255 
Nitrogen, 59 
dioxid, 63 
monoxid, 62 
pentoxid, 64 
tetroxid, 64 
trioxid, 64 
Nitroglycerol, 230 
Nitrous oxid, 62 
Nomenclature, 12 
Nuclein, 227, 233 
O 
Oils, fixed, 230 
volatile, 230 
Olefins, 177, 207 
Opium, 263 
20 306 
INDEX. 
Organic substances, 98, 171, 176 
Orientation, 248 
Orpiment, 83 
Oxalates, 217 
Oxhydryl, 29 
Oxidation, 21 
Oxids, 21 
basic, 24 
neutral, 24 
Oxyacids, 9 
Oxygen, 20 
Oxysalts, 9 
Ozone, 24 
p 
Palladium, 121 
Paraffin, 178, 179 
Paraffins, 177 
Paraglobulin, 280 
Paris green, 82 
Pepsin, 281, 285 
Peptone, 277, 281 
Peptoxin, 282 
Perissads, 7 
Petroleum, 178 
ether, 179 
Phenol, 249 
Phosphorus, 67 
chlorids, 74 
oxids, 74 
pentoxid, 74 
trioxid, 74 
Piperidin, 256 INDEX. 
307 
Piperin, 257 
Plaster of Paris, 146 
Platinum, 121 
Poisons, 42, 85 
Polymerism, 178 
Potash, 182 
Potassium, 123, 131 
bromid, 134 
carbonate, 137 
chlorate, 136 
chlorid, 134 
cyanid, 202 
dichromate, 102 
hydroxid, 132 
hypochlorite, 137 
iodid, 135 
nitrate, 136 
permanganate, 103 
sulfates, 137 
tartrates, 235 
Propeptones, 281 
Protagon, 233 
Proteids, 274 
Prussian blue, 107 
Ptomains, 218, 269 
Ptyalin, 285 
Putrefaction, 218, 275, 276 
Putrescin, 218 
Pyridin, 256 
Pyrrol, 259 
Pyroxylin, 243 
Q 
Quinin, 266 308 
INDEX. 
R 
Radicals, 174, 178 
Reaction, 11 
Realgar, 82 
Red lead, 112 
Reduction, 20 
Respiration, 23, 212 
Rhigolene, 178 
Rubidium, 123 
s 
Saleratus, 130 
Saltpetre, 136 
Salts, 9 
formation of, 10 
haloid, 9 
oxy, 9 
Saponification, 231 
Saprin, 218 
Sarkin, 226 
Scandium, 108 
Scheele’s green, 82 
Scliweinfurt green, 82 
Selenium, 49 
Silicon, 98 
dioxid, 98 
Silver, 123, 139 
cyanid, 202 
nitrate, 140 
Soap, 232 
Soda, 125, 129 INDEX. 
309 
Sodium, 123, 124 
bromid, 127 
carbonates, 129 
chlorid, 126 
hydroxid, 125 
hypochlorite, 129 
iodid, 127 
nitrate, 127 
phosphates, 128 
pyroborate, 129 
sulfates, 127 
Solution, 25 
Spirits, 185 
Stannous chlorid, 119 
Starch, 242 
Steel, 104 
Stoichiometry, 11 
Strontium, 144 
Strychnin, 268 
Substitution, 179 
Sugar, cane, 241 
diabetic, 237 
grape, 237 
milk, 241 
of lead, 114 
Sulfur, 49 
dioxid, 53 
trioxid, 55 
Symbols, 8 
Synthesis, 3, 28 
Syntonin, 280 
Tannin, 273 
T 310 
INDEX. 
Tartar, cream of, 235 
crude, 235 
emetic, 236 
Tellurium, 49 
Test, Boettger’s, 239 
Fehling’s, 238 
fermentation, 239 
for albumen, 277 
for albuminoids, 276 
for alkaloids, 262 
for aluminium, 110 
for ammonium, 142 
for arsenic, 88 
for bile, 199, 286 
for bismuth, 118 
for blood, 284 
for bromids, 45 
for brucin, 269 
for calcium, 150 
for carbolic acid, 250 
for carbon dioxid, 212 
for chlorids, 42 
for chloroform, 181 
for copper, 159, 160 
for glucose, 238 
for hydrocyanic acid, 203 
for iodids, 47 
for iron, 106 
for lead, 115 
for lithium, 137 
for magnesium, 152 
for meconic acid, 265 
for mercury, 167 
for morphin, 264 INDEX. 
311 
Test, for nitrates, 66 
for oxalic acid, 216 
for ozone, 25 
for phenol, 250 
for phosphates, 76 
for phosphorus, 71 
for potassium, 137 
for quinin, 267 
for silver, 140 
for sodium, 137 
for starch, 242 
for strychnin, 268 
for sulfates, 57 
for sulflds, 53 
for tin, 120 
for uric acid, 225 
for zinc, 155 
Gmelin’s, 286 
Marsh’s, 89 
Mitscherlich’s, 71 
murexid, 225 
Pettenkofer’s, 199 
Reinsch’s, 87, 90, 168 
Trommer’s, 238 
Tetanin, 270 
Thebain, 265 
Theobromin, 227 
Tin, 119 
Titanium, 119 
Toxicology, of ammonia, 14 X 
of arsenic, 83 
of atropin, 258 
of barium, 150 
of carbolic acid, 251 312 
INDEX. 
Toxicology, of carbon monoxid, 209, 284 
of carbon dioxid, 211 
of chloral, 195 
of coniin, 258 
of copper, 159 
of digitalis, 272 
of hydrochloric acid, 43 
of hydrocyanic acid, 203 
of hydrogen sulfid, 53 
of lead, 116 
of mercury, 168 
of mineral acids, 43 
of nitric acid, 43 
of opium, 265 
of oxalic acid, 215 
of phenol, 251 
of phosphorus, 69 
of potash, 138 
of potassium, 138 
of soda,138 
of strychnin, 268 
of sulfur dioxid, 54 
of sulfuric acid, 43 
of tobacco, 263 
of zinc, 155 
Toxins, 269 
Toxalbumens, 285 
Triamins, 217 
Trimethylamin, 197 
Trinitro-glycerol, 230 
Trinitro-phenol, 251 
Triple phosphate, 152 
Trypsin, 281, 285 
Turnbull’s blue, 107 INDEX 
313 
Turpentine, 270 
Types, 174 
Typhotoxin, 270 
u 
Urea, 204, 220 
Ureas, compound, 224 
Ureids, 224- 
V 
Valence, 7 
Vaselin, 178, 179 
Vermilion, 167 
Vinegar, 191 
Water, 25 
hardness of, 32 
lead in, 30 
of crystallization, 26 
organic matter in, 30 
purification of, 32 
Waters, natural, 29 
Weights, 291 
White lead, 115 
vitriol, 154 
Wines, 185 
W 
X 
Xanthin, 226 314 
INDEX. 
Yeast, 184 
Y 
Z 
Zinc, 151, 153 
chlorid, 154 
oxid, 153 
sulfate, 154 
Zirconium, 119