& '. 'r- 'JT. //f^^^Y *c- \i' to/^W «. rJfl BLv*< v V J Hpm 1 ^"■;5r.- ^5 « *5? ^ OCC DC Q'O Q'OiyoO'OL-'O^-J 0 \,> wO'Q^YO'^ Surgeon General's Office mmmmm a.o ojy^z: z»OQjG .^:n O'OOOO'iO'^Q- a f- £y. H^lISTD book PRACTICAL CHEMISTRY, PRINTED (NOT PUBLISHED) FOR THE USE OF THE STUDENTS AGRICULTURAL COLLEGE OP MARYLAND. BALTIMORE: PRINTED BY SAMUEL SANDS MILLS, Publication Office " Rural 'Register," 122 Baltimore Street. 1861. QD "Hi 36 \6C\ ■A. SYNOPSIS OF THE MOST IMPORTANT TESTS FOR ASCERTAINING THE PRESENCE OF THE MORE COMMON CHEMICAL COM- POUNDS, ESPECIALLY WHEN IN SOLUTION. 1. Alkalies and their Salts. These are not precipitated by carbonate of ammonia, sulphuretted hy- drogen (H S), or sulphuret of ammonium (N H3, H S). 2. Salts of Potassa. Tartaric acid, in excess and in a concentrated solution, produces, es- pecially after violent agitation, a white crystalline precipitate. (Tartar, § 194.) Platinum solution gives a yellow crystalline precipitate. (Chloride of platinum and potassium, § 394.) 3. Salts of Soda. Antimoniate of potassa produces, in neutral, or alkaline solutions of soda salts, a white precipitate. (Antimoniate of soda, § 404.) 4. Salts of Ammonia. Caustic lime or caustic potassa, especially on heating, liberates the am- monia, which is easily recognized by its pungent odor. Heated on plati- num foil, the salts of ammonia are readily volatilized. (§ 229.) Platinum solution reacts in the same manner as with potassa salts. (§392.) 5. Alkaline Earths. These are precipitated by carbonate of ammonia, as carbonates of a white color, but not by H S or N H3, II S. 6. Salts of Baryta and Strontia. Sulphuric acid produces a white precipitate, insoluble in acids (sulphate of baryta and of strontia.) The baryta salts impart a yellowish color, and the strontia salts a crimson color, to the flame of alcohol. (§ 248.) 7. Salts of Lime. Sulphuric acid produces only in concentrated solutions of lime^a pre- cipitate, which is redissolved in a large proportion of water. (§ ~^ ) Oxalic acid and ammonia indicate mere traces of lime by a milky tur- bidncss. (Oxalate of lime, §197.) 8. Salts of Magnesia. Sulphuric acid causes no precipitate or turbidness. (§249.) _ J'hosphatc of Soda and Ammonia produce, but not immediately, in di- luted solutions, a white crystalline precipitate. (Phosphate of magnesia and ammonia, § 251.) 9. Salts of Alumina. These are precipitated by ammonia, carbonate of ammonia, and also by N H3, H S, as hydrate of the oxide of alumina. Potassa in excess dis- solves the hydrate of oxide of alumina, which is again precipitated by chloride of ammonium. (§ 260.) They are colored blue on being heated to redness with cobalt solution. (§ 262.) 10. Metallic Salts. Ammonia precipitates from their solutions the oxides as hydrates; car- bonate of ammonia also precipitates them (partly as carbonates, and partly as hydrated oxides.) H S added to an acid solution precipitates the following metallic oxides as sulphurets: a.) Black; lead, bismuth, copper, silver, mercury, platinum, gold. b.) Dark brown; tin (protoxide.) c.) Orange; antimony. d.) Yellow; tin (peroxide), cadmium, arsenic. Of these, the sulphurets of platinum, gold, tin, antimony, and arsenic, are soluble in N H3, H S. N H3, H S precipitates also as sulphurets the following, which are not precipitated by sulphuretted hydrogen alone from their acid solutions : a.) Black; iron, cobalt, nickel. &.) Flesh-colored ; manganese. c.) White ; zinc (also alumina and oxide of chromium as hydrates.) 11. Salts of Protoxide of Iron. Ammonia; a greenish-white precipitate, passing to dark green, and finally to reddish-brown. (Hydrated protoxide of iron, § 285.) Ferrocyanide of potassium ; alight blue precipitate, becoming final lv dark blue. (§292.) 6 * Tincture of nutgalls ; a violet precipitate, passing gradually to blue- black. (Tannate of protoxide of iron, § 285.) 12. Salts of Sesquioxide of Lou. Ammonia; a reddish-brown precipitate. (Hydrated sesquioxide of iron, § 285.) Ferrocyanide of potassium ; a dark-blue precipitate. (Prussian blue § 2y-) Tincture of nutgalls; a blue-black precipitate. (Tannate of sesquioxide of iron, § 285.) 5 13. Salts of Manganese. Ammonia; a white precipitate, soon passing to light and then dark brown. (Hydrated protoxide of manganese, § 300.) H S ; a flesh-colored precipitate. (Sulphuret of manganese, § 300.) 14. Salts of Cobalt. Potassa; a blue precipitate, gradually becoming green. (§ 307.) Bloupipe ; melted with borax, they give a blue bead. (Cobalt glass, 15. Salts of Nickel. Potassa; a light green precipitate. (Hydrated protoxide of nickel. § 307.) 16. Salts of Zinc. Ammonia; a gelatinous white precipitate (hydrated oxide of zinc,) which redissolves in an excess of ammonia; white sulphuret of zinc is pre- cipitated from this solution by N H3, H S. Blowpipe; heated with carbonate of soda upon charcoal, a yellow in- crustation is formed, which becomes white on cooling. (Oxide of zinc, § 310.) 17. Salts of Tin. Solution of gold causes in solutions of protoxide of tin a purple-red color or precipitate. (Gold purple, § 322.) H S ; in the protoxide solutions, a dark-brown precipitate (protosul- phuret of tin) ; in the perchloride solutions, a yellow precipitate. (Bi- sulphuret of tin, § 325.) 18. Salts of Lead. Sulphuric acid; a white precipitate insoluble in acids. (Sulphate of lead.) The same is rendered black immediately by N H3, H S. (§335.) Blow-pipe; heated with carbonate of soda upon charcoal, malleable metallic beads are formed, together with a yellow incrustation upon the coal. (§ 331.) 19. Salts of Bismuth Water, added largely to solutions of bismuth, causes a white turbidness, with a precipitation of a basic salt of bismuth. (§ 347.) Blowpipe ; if heated with carbonate of soda upon charcoal, we obtain brittle metallic beads. (§ 345.) 20. Salts of Copper. Ammonia causes a greenish-blue precipitate, which redissolves in an excess of ammonia, forming a deep blue liquid. (§ 353.) Ferrocyanide of potassium; a purple red precipitate. (Ferrocyanide of copper, § 292.) Polished iron; a deposition of metallic copper. (§152.) Blowpipe; when heated with carbonate of soda upon charcoal, and washed with water, spangles of metallic copper are obtained. (§ 355.) 6 L>1. Salts of Mercury. Potassa precipitates from protoxide salts black protoxide of mercury q 368) ; from the peroxide salts, yellowish-red peroxide of mercury. Pratnchloride of tin precipitates on boiling metallic mercury. (§ 375.) Cupper, on being rubbed with a solution of mercury, assumes a silvery appearance. (369.) 22. Salts of Silver. Muriatic acid; a white, curdy precipitate, soluble in ammonia. (Chlo ride of silver, § 381.) Blowpipe; heated with carbonate of soda upon charcoal, glistening malleable metallic beads are formed. (§ 381.) 23. Salts of Gold. Protochloride of tin; a purple-red precipitate. (Gold purple, §388.) Green vitriol; a precipitate of gold powder. (§ 387.) 24. Salts of J'/atinum. Potassa; a yellow crystalline precipitate. (Chloride of platinum and potassium, § 394.) Blowpipe; reduces the salt to a metal. (§ 393.) 25. Salts of Sesquioxide of Chromium. Potassa; a bluish-green precipitate (hydrated oxide of chromium,) soluble in an excess of potassa, forming a dark green solution. (§ 400.) 26. Salts of Chromic acid.} Sugar of lead; a yellow precipitate. (Chrome yellow, § 399.) Sulphurir arid and alcohol; conversion of the yellow or red color into green by heating. (§ 400.) 27. Compounds of Antimony. HS; an orange-colored precipitate. (Sulphuret of antimony, § 407.) Blowpipe; heated with carbonate of soda, brittle metallic globules are formed; and also white fumes and a white incrustation upon the charcoal. (§ 403.) Marsh's test (§ 418.) 28. Compounds of Arsenic H S ; a yellow precipitate. (Sulphuret of arsenic, § 416.) Reduction test (§ 413.) Marsh's test (§ 417.) 29. Salts of Sulphuric Acid. Chloride of barium; a white pulverulent precipitate, insoluble in acids (Sulphate of baryta, § 171.) Sugar of lead/ a white precipitate, insoluble in diluted acids (Sul- phate of lead, § 335.) 30. Salts of Sulphurous Arid. Sulphuric arid evolvesa gas having the odor of burning sulphur. (§ 174.) 7 31. Salts of Phosphoric Acid. Chloride of barium ; a white precipitate soluble in acids. Silver solution; a yellow precipitate. (Phosphate of silver, § 176.) Solution of magnesiaand ammonia; a white precipitate. (See No. 8.) 32. Salts of Boracic Acid. Chloride of barium ; a white precipitate soluble in acids. Sulphuric acid and alcohol, when heated with them, present a green flame. (§ 182.) 33. Salts of Nitric Acid. Indigo solution and sulphuric acid; by boiling, the feeble blue-colored liquid is changed in color by the liberated nitric acid. Glowing charcoal causes a deflagration of the nitrates. (§ 207.) 34. Salts of Chloric Acid Act like the nitrates towards solution of indigo, and upon glowing char- coal ; but when heated with muriatic acid, they evolve the odor of chlo- rine. (§ 150.) 35. Chlorides or Salts of Muriatic Acid. Silver solution; a white, curdy precipitate of chloride of silver, readily soluble in ammonia. (§ 186.) Peroxide of manganese and sulphuric acid; evolution of chlorine on heating. (§ 151.) 36. Iodides. Silver solution; a yellowish precipitate of iodide of silver difficultly solu- ble in ammonia. Peroxide of manganese and sidphuric acid evolve iodine in violet fumes. (§ 210.) Starch paste and nitric acid ; blue color. (Iodide of starch, § 155.) 37. Sulphurets. Muriatic acid evolves from most of them a gas having the odor of rot- ten eggs. (H S, §§ 132, 213.) 38. Salts of Carbonic Acid. Muriatic acid liberates from them with effervescence an odorless gas. (§§ 202, 237.) Lime-water is rendered milky by them. (Carbonate of lime, § 115.) 39. Salts of Oxalic Acid. Solution of gypsum causes a white precipitate. (Oxalate of lime, §197') Heated upon platinum foil, they are decomposed without charring. (§ 197.) 40. Suits of Tartaric Acid. Potassa precipitates tartar, as in No. 2. (§ 194.) Heated on platinum foil, they are decomposed with separation of much carbon, and give off the odor of burnt sugar. (§ 194.) 41. Salts of Acetic Acid. Sulphuric acid produces on heating an odor of vinegar. Sulphuric acid and alcohol, an odor of acetic ether. (§ 198.) Heated, they are charred, and give off the odor of vinegar. (§ 198.) T -A. 33 31 E Showing thb Action of Reagents on Oxides and Acids. (Alphabetically arranged.) 1. Metallic Bases, (In Combination.) Name of Base. Hydro-sulplluric Acid (Sul-Symbol. \ phuretted Hydrogen) (HS).in an acidified j solution. Hydro-sulphate of Ammonia (NH,S, HS). Carbonate of Soda, (NaO, CO, Carbonate of Ammonia (2NHtO, 3CO,). Potash (KO). Ammonia (NH,). Ferro-cyanide of Potassium (K,FeCy,). Blowpipe. Remark*. Alumina. Al,0, 0 White ; insol. in excess. White; insol. in excess. White; insol. White; sol. in excess. White; insol. O Blue with nitrate of cobalt. These precipitates are insoluble in muriate of ammonia. Antimony oxide of SbO, Orange red. Orange red; sol. in excess. White; sparingly soluble. White; sp. sol. White; sp. sol. in excess. White; insol. White. With soda in deoxodizing flame, reduced, and gives off white fumes of oxide. The chloride decomposed by water. Baryta. BaO. O O White; insol. in excess. White; insol. O O O O Thrown down immediately with sulphates and sulphate of lime. Bismuth, Bi,0, j Brown-oxide of black. Brown-black ; insol. in excess. White; insol. in excess. White; insol. White; insol. White; insol. White. With soda on charcoal reduced; brittle bead of metal. Nitrate decomposed by water. Cadmium, oxide of. CdO. Bright yellow. Bright yellow; insol. in excess. White; insol. in excess. White; insol. White ; insol. White; sol. in excess White. With soda on char-coal reduced and metal volatilized; leaves a reddish brown deposit. The yellow sulphide, insol. in hydrosulp. of ammonia, is highly characteristic. Calcium (Lime). CaO. O O White; insol. in excess. White; insol. O 0 O Radiates a brilliant light. Gives a red color to the flame. Oxalate of ammonia . causes a white pre-cipitate even in very dilute solutions. Chromium, oxide of. Cr,0, O Green. Green. Green. Green; sol. in excess. Green; insol. O Emerald green with fluxes. The oxide when fused with nitre, gives ohromate of potash. Cobalt, oxide of. CoO. O Black. Pink; insol. Bluish on boiling. Pink; sp. sol. in ex. solution purple. Blue; becoming greenish; dirty red on boiling. Blue; sol. in ex. forming a brownish red sol. Pale green or gray. Blue glass, with borax in both flames. Readily distinguished with the blowpipe. Copper, oxide of. CuO. Black. Black. Greenish blue, becom-ing dark brown on boiling. Greenish blue, sol. in ex. forming deep blue solution. Pale blue, becoming dark brown when boiled. Pale blue, sol. in ex. forming rich blue solution. Mahogany colored; insol. With soda on char-coal reduced. With borax and mic. salt in outer flame, green; in inner flame red. Precipitated in the metallic state by clean iron; and as the black oxide by zinc. Glucina. GIO 6 O O White; sp. sol. White ; sol. in ex. White; sol. in ex. White; insol. O With nitrate of cobalt, dark gray or black. Glucina dissolves in cold solution of carb. ammonia, and is thrown down on boiling. Gold, teroxide of. AuO, Black. Brown-black ; sol. in excess. o Yellow; insol. Yellowish brown. Yellow; insol. O Reduced. Thrown down in the form of a brown metallic powder, boiled with proto-sulph. iron. Iridium, sesquioxide of. lr,0, Slight brown. . Brown ; sol. Brown red ; sp. sol." Bleaches the solution. Slight brown The solution becomes first colorless, and subse-quently bluish. As with potash. On exposure to the air a slight blue precipitate falls. Solution slowly dis-colored. Reduced. The solutions have a deep brown color. Iron, protoxide of. FeO. O Black. White, then green, and ultimately rust-colored. As with carbonate of soda. White beco-ming green, and on stand-ing, rust-colored. As with potash; but becoming brown more rapidly. White; instantly changing to light blue. With the fluxes in the outer flame, brownish-yellow; in the inner flame, light green. Deep blue precipitate with ferridcyanide of potassium. Nnmeof Base. Symbol. Hydro-i.Aphuric Acid (HS) in an acidified solution. Hydro-sulphate of Ammonia (NHtS, HS). Carbonate of Soda (NaO, CO.). Carbonate of Ammonia C2NHt0, 3C0,). Potash (KO). Ammonia (NH,). Ferro-cyanide of Potassium (K,Fe,Cy,). Blowpipe. Remarks. Iron, peroxide of Fe.O, Yellowish white pre-cipitate of sulphur. Black. Rust-colored. Rust-colored. Rust-colored. Rnst-colored. Deep-blue. As the protoxide. Black with infusion of nutgalls. Lead, oxide of. PbO. Black. Black. White; insol. White ; insol. . White; sol. White; insol. None at first with the acetate. White. \ With soda on char-coal reduced; yellow deposit also formed on the charcoal. Precipitated by solu-ble sulphates, and the precip. blackened by lydrosulphate of am-monia. Bright yellow with chromate of pot-ash and iodide of potassium. Lithia. LiO. O O Faint white in concentra-ted sol. As carb. soda. O O O Gives red color to the flame. Phos. of soda and am-monia gives a white precipitate. Magnesia. MgO. O O Flesh colored. White; insol. O White; insol. White; insol. o Light pink with nitrate of cobalt. Crystalline precipitate with phosphate of soda and ammonia. The carbonate and hy-drate sol. in muriate of ammonia. Manganese, protoxide of. MnO. 0 White; insol. White; insol. White, becoming brown. White; becoming brown. White. With soda a green bead. With borax in outer flame an amethyst bead, which loses its color in the reducing flame. The presence of am-nxoniacal salts pre-vents more or less completely the pre-cipitation of manga-nese by the alkalies. Mebcury, protoxide of. HgO. Black. Black. Dark-gray. Dark-gray. Black; insol. Black; insol. White. Mixed with soda and heated in a tube, the metal sublimes. White precipitate with chlorides, black ened by ammonia. Volatilized or decom posed by heat. ■ | Mercury, peroxide of. HgO, White, tuni-ng to black. White, turn-ing to black. Reddish brown; insol. White; insol. Yellow; insol. White; insol. White. As the protoxide. Volat'zed or decomp'd by heat. Beautiful scarlet with iodide of potassium. Molybde-num, oxides of. MoO and MoO, Brown-black, slowly formed. Yellowish-brown ; sol. .Brown; sol. Brown; sol. Brown-black ; insol. Brown-black ; insol. Brown with the binoxide. With microcosmic salt in outer flame, a green glass. Most readily distin-guished by the 1 blowpipe. Nickel, oxide of. Osmium, deutoxide of. mo. "0 Black. Pale green; insol. Pale green; soluble; forming green solu-tion. Pale green; insol. Pale green ; soluble, forming a blue solu-tion. Pale green. With soda on char-coal, reduced to a magnetic powder. With borax and mic. salt in outer flame, red glass, becoming color-less on cooling. Potash throws down a pale-green precipitate from the ammoniacal solution. OsO, Yellowish-brow, slowly formed. Yellowish-brown ; insol. Black, slowly formed. Bluish solution. Brown after some time. Black on boiling. Brown after some time. . 0 Osmium is characterized by forming, when heated in the air, a suboxide, which is vola-tile, and has a very disagreeable smell, caus-ing much inconvenience to the eyes and nose. Palladium, protoxide of. PdO. Black. Black; insol. Brown; sol. Reprecipita-ted on boil-ing. Solution decolorized, but no pre-cipitate. Yellowish-brown; soL Yellowish brown; sol. o Reduced. Yellowish-white with solution of cyanide of mercury. Platinum, oxide of. PtO, Brownish-black, formed slowly. Brownish-black ; sol. in large excess. Yellow with carbonate of potash. Yellow. Yellow. Yellow. o Reduced. Yellow with muriate of ammonia, which is converted by heat into spongy platinum. Potash. KO. O O O O O O o Violet flame. White crystalline precipitate with tar-taric acid. Yellow with bichloride of platinum. Rhodium, sesquioxide of. R»o, Brown, formed slowly. Brown; insol. Yellowish after a time. Yellowish after a time. Yellowish brown on boiling. Yellowish after a time. Dark orange. Reduced. Many oi the compounds have a rose-color. Silver, oxide of. AgO. Black. Black. White; insol. White; sol. Pale brown; insol. Pale brown; sol. White. Reduced. White curdy precipi-tate, with hydrochlo-ric acid and chlorides, which is sol. in am-monia and insol. in nitric acid. Soda. NaO. O O O O O O O Yellow flame. The only salt which precipitates soda is the antimoniate of potash. Evaporated with bichloride of platinum gives yellow needles. Name of Base. Symbol. Hydro-sulpnuric Acid, (HS), in an acidified solution. O Hydro-sulphate of Ammonia (NH.S, HS). O Carbonate «f Soda, (NaO, CO, Carbonate Ammonia (2NHt0, 3C0,). White ; insol. White; insol. Potash (KO). Ammonia (NH,). Ferro-cyanide of Potassium (K,FeCys). O Blowpipe. lit-marks. White precipitates with sulphates. Burnt with alcohol, jives carmine llame. Zinc throws down the metal in beautiful crystals. The behavior with hydrosulphate of am-monia and the blow-pipe are characteristic. When the precipitate] with ammonia is 1 heated, it is converted into the green Strontia. SrO. White ; insol. O O Carmine flame. Tin, protoxide of. S7l0. Brown-black, Brown-black. White; insol. White; insol. White; sol. White ; insol. White. With soda in reducing flame, a malleable bead of metallic tin. Tin, peroxide of. Uranium, sesquioxide of. SnO, Yellow. Yellow; sol. White ; insol. White; sol. White; sol. White. Reddish-brown. Reduced with soda. U,0, 0 (Sulphur.) Black. Yellow; sol. Yellow; sol. Yellow; insol. Yellow; insol. Yellow glass with borax. Vanadium, binoxide of. V0a 0 Brown-black ; sol. in excess forming a purple solution. Dirty white. Gray, passing to brown. Grayish-white. Brown. Yellow. With borax, yellow in outer ilame; in the inner, brown, becoming green when cold. Many of the solutions have a blue color. Yttria. YO. 0 White. White; sp. sol. White; sp. sol. White; insol. White; insol. White. Nothing characteristic. Copious white with oxalic acid. Zinc, oxide of. ZnO. O White. White; insol. White; sol. White; sol. White; sol. White. With soda on charcoal gives a white subli-mate of oxide, which is yellow when hot. With nit. cobalt, green. Behavior with hydro-sulphate of ammonia characteristic. Zieconia. Zr,0, 1 0 White. White after - a time. White; sol. White; insol. White; insol. White. Bright flame. Oxalic acid gives a white precipitate. 2. Metallic Oxides having acid properties. Acids (in combination.) Symbol. Hydro-sulphuric Acid, (HS), in acidified solutions. Hydro-sulphate of Ammonia (NH.S, HS). Chloride of Barium (BaCl), (in alkaline salts of the acids). Nitrate of Silver (AgO, NO' ) (in alkaline salts of the acids). Nitrate of Lime (CaO, NO* ) (in alkaline salts of the acids). Hydro-chloric acid (HCl). Remarks. Antimonious Acid. SbO< Orange. Orange; sol. White; sp. sol. in water. White. White; sp. sol. in water. White, o Antimonious acid becomes pale-yellow when heated, and white again on cooling. It is in-soluble in nitric acid, and difficultly soluble in hot hydrochloric acid. Antimonic Acid. SbO' Orange. Orange; sol. White. White. White.' White. insoluble in water and nitric acid. Soluble in hydrochloric acid, from which it is precipitated on the addition of water. When strongly heat-ed, gives off oxygen, and becomes antimonious acid. Arseniocs Acid. AsO, Yellow; soluble in alkalies and alkaline sulphides. Yellow; sol. White. Pale yellow. White. O Volatilizes at a low heat, and condenses in octo-hedral crystals. The best tests are Marsh's and Reinsch's. Arsenic Acid. AiO* Yellow; soluble in alkalies and alkaline sulphides. Yellow; sol. White. Chocolate-brown. White. O Heated with black flux, gives metallic arsenic. Chromic Acid. CrO, Reduced to oxide with precipitation of sulphur. Green. Yellow. Reddish-brown. Yellow in concentrated solutions. Reduced to oxide, with evolution of chlorine. Is decomposed by heat and by deoxidizing agents, into oxide of chromium. Salts of lead throw down a yellow precipitate. Manganic Acid. MnO, O Flesh colored. O Black (oxide). Black. Solution becomes red and .chlorine is evolved. Converted by acids into hyper-manganic acid and peroxide of manganese; the color of the solu-tion changing from green to red. Molybdic Acid. MoO, Brown. Brown; sol. White. White. White. White. With microcosmic salt before the blowpipe, gives a dark-blue glass, which becomes green on cool-ing. When strongly heated, molybdic acid volatilizes and condenses in crystals. Tungstic Acid. WO, Slight turbidity. Brown; sol. White. White. White. White; insol. Does not volatilize when heated. Has a pale-yellow color, and is insoluble in water and acids. When treated with hydrochloric acid, the mix-ture is capable of dissolving gold-leaf. Vanadic acid in solution is readily deoxidized, forming a blue liquid. | Vanadic Acid. vo; Gray. Brown. sol. Orange. Yellow. O Chlorine evolved. 3. Non-metallic Acids. Acids (neutralized.) Symbol. Nitrate of Baryta (BaO,NO' ). Nitrate f Silver AgO,NOs ). Nitrate of Lime (CaO,NO* ). Acetate of Lead (PbO, C,H,0,). Remarks. Boracic Acid. BO, White. White. White. (Slightly volatile in the presence of aqueous vapor. Turns turmeric paper White. brown, and blue litmus port-wine color. Gives green color to the name of alcohol. Bromic Ann. BrO* White. White. O The bromates are decomposed by heat into bromides and oxygen. Sulphu-White. | ric acid disengages bromine. Carbonic Acid. CO, White. White. White. White. The carbonates are readily decomposed by acids, carbonic acid gas being given off with effervescence, which, when passed into lime water, gives a white precipitate. Chlokic Acid. CIO" O O O O j All the chlorates are soluble in water. At a red heat they are converted into | chlorides, oxygen being given off. , Hydriodic Acid. HI. O Pale-yellow. O Bright yellow. The iodides evolve iodine when heated with nitric or sulphuric acid. With chlorine water and starch, they give a dark-purple precipitate. Hydrobromic Acid. HBr. O Yellowish o White. The bromides, when heated with nitric acid, evolve bromine. Hydrochloric Acid HCl. O White. o White. The chlorides, when heated with peroxide of lead, or of manganese, evolve chlorine. Hydrocyanic Acid. H,C,N. O White. o White. With a mixture of protosalt and persalt ot iron, the alkaline cyanides give a precipitate of Prussian blue. Hydrofluoric Acid. HF. White. White. White. White. The fluorides, when moistened with sulphuric acid, give off fumes which corrode glass. The selenides, when heated in the outer flame of the blowpipe, evolve the odor of selenium, resembling that of putrid horse radish. Hydroselenic Acid. HSe. O Black. O Black. Hydrosulphuric Acid. HS. O Black. O Black. Most of the sulphides, when treated with an acid, evolve hydrosulphuric acid, which smells like rotten eggs. Hyposulphurous Acid. S,0, White. White; becoming brown. o White. The hyposulphites are decomposed by hydrochloric acid; sulphur is pre-cipitated, and sulphurous acid set free. Hyposulphuric AciD. S>0* 10' O O o O The hyposulphates are decomposed without deposition of sulphur, when boiled with hydrochloric acid; sulphurous and sulphuric acids are formed. Iodic Acid. White. White. White. White; The iodates are decomposed by heat into iodides and oxygen. When mixed with sulphuric and hydrochloric acids, the nitrtates dissolve gold leaf. With copper filings and sulphuric acid, orange fumes are given off. Nitric Acid. NO* O O O O Perchloric Acid. CW 0 0 O O The perchlorates are resolved by heat into chlorides and oxygen. They are not decomposed in the cold by hydrochloric or sulphuric acid ; thus differ-ing from the chlorides. Phosphoric Acid (Tribasic). PO' White. Pale Yellow. White. White. The soluble phosphates give with salts of magnesia, when ammonia is present, a white crystalline precipitate. Phosphorous Acid. PO, White. White, becoming brown. White. White. The hydrated phosphites are decomposed when heated in a tube; hydrogen is given off, and phosphates are formed. Selenic Acid. SeO, White. White. White. White. The seleniates are decomposed by boiling with hydrochloric acid ; chlorine! is evolved, together with selenious acid. Seleniovs Acid. SeO, White. White. White. White. Metallic zinc or sulphurous acid causes the precipitation of selenium from acidified solutions of the selenites. Silicic Acid. SiO, White. Pale yellow. White. White. When a solu decomposed Most ofthesi which, when Me silicate is evaporated to dryness with hydrochloric acid it is , and the silica remains insoluble. Sulphuric Acid. SO, White. White crystalline. White crystalline. White. ilphates when heated with charcoal are converted into sulphides, moistened with hydrochloric acid, evolve hydrosulphuric acid. Sulphurous Acid. SO, White. White. White. White. The sulphites are decomposed by sulphuric acid, sulphurous acid being given off without the deposition of sulphur. 4. Organic Acids. Acids (neutralized). Symbol. Chloride of Calcium (CaCl). Perehloridc of Iron (Fe,Cl,). Nitrate of Baryta (BaO,NO' ). Nitrate of Silver (AgO, NO*). Acetate of Lead (PbO, CAH,0,). Remarks. Acetic Acid. H0,C4 H,0. O O O White crystalline in concentrated solutions. O The acetates, when warmed with sulphuric acid, give off the smell of vinegar. Acetic acid boiled with an excess of protox-ide of lead, forms the subacetate, which is alkaline to test-paper. Benzoic Acid. HO, C H 0 14 5 3 o Brownish-Yellow. O Crystalline in concentra-ted neutral solutions. White in concentrated neutral solutions. Solutions of the benzoates, when treated with sulphuric acid, give a crystalline precipitate of benzoic acid. Citric Acid. 3H0, C H 0 12 6 12 White. O White. White. White. With protonitrate of mercury, a white precipitate, which be-comes gray. Formic Acid. HO, C,HO, O O O White; beco-ming black, especially when warmed. O The formiates, when warmed with sulphuric acid, do not black-en, and give off carbonic oxide gas. Malic Acid. 2H0, CeH.O, White on the addition of alcohol. o White. White; becoming Gray. White preci-pitate that melts in boil-ing water. Malate of lead dissolves in hot dilute acetic acid, and crystal-lizes on cooling in fine needles. Malic acid is decomposed by heat, into malseic and fumaric acids. Oxalic Acid. HO, c,o, White. Yellowish-brown. SV hite crystalline. White. White. Neither the acid nor the oxalates are blackened by strong sul-phuric acid, but give off carbonic acid and carbonic oxide gases. Succinic Acid. HO, C4H,Ot O Reddish brown. O White on standing. White. A mixture of chloride of barium, ammonia, and alcohol, gives a white precipitate of succinate of baryta. Tartaric Acid. 2HO, CHO 8 4 10 White. O White. White. White. Added in excess to potash, gives a crystalline precipitate of the bitartrate. T -A. 33 3L, E Showing the Behavior of Solutions of the Metals with Hydrosulphuric acid, Hydrosulphote of Ammonia, and Gtrbonate of Ammonia, employed successively. {Dr. WiU.)—(The rarer metals are printed in italics) Elements precipitated from their acid solutions by Hydrosulphuric Acid, as Sulphides. Soluble in Hydrosulphate of Ammonia, ana reprecipitated by Hydrochloric Acid. Antimony. . Orange. Arsenic . ~) f Yellow. Tin ... ) Gold. . . > Platinum > Black. Iridium . Molybdenum . Brown, Insoluble in Hydrosulphate of Ammonia. Mercury Silver . Lead . . Bismuth Copper . Cadmium Palladium Rhodium . Osmium . M YeUow. ! r * § Bodies precipitated by Hydrosulphate op Ammonia. As Sulphides. Nickel . , Cobalt . . Manganese Iron . . . Zinc . . . Uranium Black. f Flesh- ly colored Black. White. | Brownish ( black. As oxides. Alumina . Glucina . Chromium Thorina . Yttria . . Cerium. . Zirconia . Titanium Tantalium a> -d ,3-S O Ph .9 tits As Salts. Baryta, Strontia, Lime. in combina- tion with phosphoric, boracic, oxalic and some other acids. Magnesia. in combina- tion with phosphoric acid. Bodies not precipitated by Hydrosulphuric Acid, or Hydrosulphate of Ammonia. In the presence of Muriate of Ammonia, on addition of Carbonate of Ammonia, are precipi- I not precipi- tated, tated. Baryta. Strontia. Lime, Magnesia. Potash. Soda. IAthia. Ammonia. | 17 REAGENTS. The following is a list of the reagents, &c, usually employed in testing and analysis:— Sulphuric acid, strong and dilute. Hydrochloric acid. Nitric acid. Nitrohydrochloric acid (aqua re- gia-) Oxalic acid. Acetic acid. Tartarie acid. Hydrosulphuric acid (sulphuret- ted hydrogen.) Ammonia. Hydrosulphate of ammonia. Carbonate of ammonia. Oxalate of ammonia. Phosphate of soda and ammonia (microcosmic salt.) Potash. Carbonate of potash. Nitrate of potash. Iodide of potassium. Chromate of potash. Cyanide of potassium. Ferrocyanide of potassium (yel- low prussiate of potash.) Ferridcyanide of potassium (red prussiate of potash.) Antimoniate of potash. Carbonate of soda. Phosphate of soda. Borax. Lime water. Sulphate of lime. Chloride of calcium. Chloride of barium. Nitrate of baryta. Perchloride of iron. Nitrate of cobalt. Sulphate of copper. Ammonio-sulphate of copper. Acetate of lead. Subacetate of lead. Nitrate of silver. Ammonio-nitrate of silver. Perchloride of mercury. Protochloride of tin. Perchloride of gold. Bichloride of platinum. Sulphate of indigo. Solution of starch. Black flux. Distilled water. Alcohol. Litmus and turmeric paper. 4 The following scheme exhibits the successive steps which are to be taken in order to separate the several inorganic substances from the solution in muriatic acid by the methods described. Digest the soil in distilled water, dry at 250°, weigh, digest with dilute muriatic acid for 12 hours, and filter the solution This solution should be decidedly sour, and may contain lime, magnesia, alumina, oxide of iron, oxide of manganese potash soda and phosphoric acid. ' > F 1. Add caustic ammonia in excess. 9. To the clear solution add oxalate of ammonia, and cover it from the air. 11. Add hydrosulphuret of ammonia. 13. Render sour by muriatic a- cid, boil, filter, evaporate to dryness., and heat to incipient redness to drive off all the ammoniacal salts. Redissolve in a little water, mix with a little pure red oxide of mer- cury, evaporate again to dry- ness, heat to redness, and treat with water. 12. If manganese is present it falls as sulphuret; dissolve in muriatic acid, precipitate by carbonate of soda, wash, heat to redness in the air, and weigh. 15. The solution contains the chlorides of potassium and sodium, if present. Evaporate to dryness, weigh, re-dissolve in water, and add bichloride of platinum, to separate the potash. 14. Caustic magnesia re- mains ; wash, heat to red- ness, and weigh. 17. The chloride of sodium re- mains in solution, and its weight is found by deducting from the weight of the mixed chlorides (15) that of the chloride of potassium (16). 16. Wash the precipitate with weak alcohol, dry by a gen- tle heat, and weigh. 10. Oxalate of, lime fa 1 Is, wash, heat to redness to convert it in- to carbonate, and weigh. 2. Oxide of iron alumina, and phosphoric acid are precipitated. Digest in acetic acid. 6. Solution contains alumina and oxide of iron ; add am- monia, and digest the pre- cipitate in a solution of caustic potash. i. Add muri- atic acid till the solution is sour; then ammonia in excess.— Alumina falls; wash and weigh. 3. Phosphates of alumina and iron remain undissolved. Fuse with carbonate of so- da, and wash with distilled water. 1. Oxide of iron re- mains ; wash and weigh. 5. Phosphoric acid is dissol- ved. Neutral- ize by nitric acid, and add nitrate of sil- ver, when phosphate of silver will fall ; or by muriatic acid and add chlo- ride of calci- um and caus- tic ammonia, when bone earth will fall 4. Alumi- na and oxide of iron re- main ; dissolve in muri- atic acid, and add to the so- lution («)■ 00 19 ASSAY NOTE, No. TESTS FOR THE METAL. Carbonate of soda, - Ammonia, - Potash, - - . . _ Red Prussiate of Potash, Sulphuretted Hydrogen, METAL INDICATED, - TESTS FOR THE ACID. Chloride of barium, - Nitrate of Silver, - Nitrate of Lead, - Chloride of Calcium, - - - ACID INDICATED, Directions.—Against the word No. , write the number that is marked upon the envelope of the salt, or upon the bottled solution which is presented to you for analysis. Fill up the blank spaces opposite the names of the tests as follows:—If you get no precipitate, insert a cypher, 0. If you get a precipitate, write P, and add the color of the precipitate, thus: P white or P brown. If the precipitate dissolves in an excess of the test, add S after the color, as P white S, P brown S. When the metal and the acid are indicated, write their names in the spaces provided for that purpose. Sign your name below. _____________.............................................Analyst. Dattlz 20 INDICATING PRECIPITANTS FOR METALS IN SALTS. Solutions to be neutral. Solutions to be Acid- METALS Indicated. "3 5 . 8 ° •£« a O "2 o e a < Potash. Red Prussiate of Potash. -a a o 2 Ji ►> ? ^° 3« None. None. Noue. 1 Potassium. 2 Sodium. 3 Ammonium. None. None. None. 4 Barium. 5 Strontium. 6 Calcium. White' White White White White. ■-•is -3.S.2- Brown. Blue. None. Yellow. Black. 7 Manganese. 8 Iron, protosalts. 9 Magnesium. 10 Cadmium. 11 Bismuth. White' White White White White White. £ « <» e3 — a) ► CO B M SO « Yellow-red. White. None. Black. Yellow. Orange. 12 Zinc. 13 Tin, protosalts. 14 Aluminum. 15 Lead. 16 Tin, persalts. 17 Antimony. Black, See Gold, No. 25. Red-brown. 18 Mercury, its Protosalts. Blue, If boiled, red. Blue, If boiled, black. 19 Cobalt. 20 Copper. Green. Green. Green. Yellow-green. None. Light-blue. 21 Nickel. 22 Chromium. 23 Iron, persalts and protosalts mixed. Yellow. Yellow, Sometimes slight, and black. Yellow-red, But none from the Perchloride. None. 24 Mercury, its per-salts. 25 Gold. Brown. Brown. None. Brown. 26 Iron, persalts. 27 Silver. 21 INDICATING PRECIPITANTS FOR ACIDS IN SALTS. Nitrate of Barytes, or Chloride of Barium. Nitrate of Silver. Nitrate of Lead. Chloride of Calcium. SALTS Indicated. None. None. None. None. None. None. None. None. White. Black. Yellow. White. 1 Nitrates. 2 Chlorates. 3 Chlorides. 4 Iodides. 5 Arseuites. 6 Sulphurets. White " White White White White All 5 soluble in Nitric acid, without Effervescence. None. Yellow. Brown. White, Sol. in water. White, Insol. in water. 7 Fluorides. 8 Phosphates. 9 Arseniates. 10 Borates. 11 Oxalates. w. •. ( Soluble in Acids, \ with effervescence. 12 Carbonates. White ■{ Insoluble in Acids. 13 Sulphates. Yellow 14 Chromates. Before proceeding farther, I request you to compare these Tables with your Assay Notes, and to draw conclusions, from the results of your ex- periments, in regard to the nature of the substance which you have had to examine. EXLFijA.i>T-A.a:io3sr or THB TABLE OF DECIMAL EQUIVALENTS. The first column contains the common^ English names of certain com- pounds. The second and fourth columns exhibit the atomic constitution of these compounds, expressed in symbols. The third and fifth columns show how much by weight of each constituent, is contained m 1 part by weight of the compound named in column first. Examples : 1 Part (that is 1 Grain, or 1 Pound) of Alumina contains 0.53295 of Aluminum. 0.46705 of Oxygen. Total, l.OOOOQ. 1 Part of Sulphate of Barytes, contains 0.65628 of Barytes. 0.34372 of anhydrous Sulphuric Acid. Total, 1.00000. Or it contains 0.58768 of Barium. 0.13797 of Sulphur. 0.27435 of Oxygen. Total, 1.00000. Examples of the use of this Table. Rule:—To find the weight of any Constituent in a given weight of a Compound.-—Multiply the given weight of the compound, by the decimal equivalent of the particular constituent. The product is the weight of that constituent. Example.—Suppose you have 25.45 grains of precipitated sulphate of barytes, and wish to know how much dry sulphuric acid it contains. To find this, you have only to multiply 25.45 by the decimal equivalent of the dry sulphuric acid contain in 1 part of sulphate of barytes. Accord- ing to the Table this is .34372. See article, " Barytes, Sulphate," page 23. The product is the weight of the dry sulphuric acid, expressed in grains. 25.45 X -34372 = 8.7476740 grains. Proof of the correctness of this calculation.—The atomic weight of sul- phate of barytes is 1458.045, and that of dry sulphuric acid is 501.165. Then by proportion :— 1458.045 : 501.165 : : 25.45 : x =8.7477. Rule :—To find how much by weight of any compound can be produced from a giren weight of one of its constituents.—Multiply the weight of the given constituent by 1.00000, and divide the product by the decimal equivalent of the given constituent, 23 The product of the division is the required weight of the compound. Example.—Given, 55J grains of Iron; required, the quantity of Pe- roxide of Iron, Fe203, which it will produce. The decimal equivalent of Iron, quoted at the article "Iron, Perox- ide," page 25, is .69338. The calculation is therefore, 55.5 X 1 = Fe203 .69338 55.50000* or, .69338 x = 80.043 grains. Proof.—The atomic weight of Peroxide of Iron, Fe203, is 978.41, and that of two atoms of Iron, Fe2, is 678.41. Then by proportion we find : 678.41 : 978.41 : : 55.50 : x = 80.043 grains. Calculations of this sort, performed with the atomic weights, are twice as long as those performed with the decimal equivalents, the numbers ex- pressing the latter being so prepared as to reduce the whole operation to a simple multiplication or division. DECIMAL EQUIVALENTS Alumina, Aluminum, Chloride, Ammonia, Ammonia, Muriate, Ammonium, Chloride, Antimony, Terchloride, —Pentachloride, —Oxide, —Sulphuret, Antimonic Acid, . Antimonious Acid, Arsenic, Terchloride, —Pentachloride, —Sulphuret, Arsenic, Sulphuret, Arsenic Acid. Arsenious Acid, Arseniuretted Hydrogen. Barium, Chloride, . — Sulphuret, Barytes, — Carbonate, Ba — Chromate, —. Nitrate, — Phosphate, 69478 Al2 .53295 O3 .46705 AP 20496 CP 79504 N 82544 H3 17456 N2H6 32030 H2CP 67970 N2H8 33894 CP 66106 Sb2 54845 CI6 45155 Sb2 42155 CI10 57845 Sb2 84317 O3 15683 Sb2 72771 SJ 27229 Sb2 76336 O5 23664 Sb2 80128 O4 19872 As2 41449 CP 58551 As2 29812 CI10 70188 As2 70029 S" 29971 As2 60903 S3 39097 As2 48311 S6 51689 As2 65280 O5 34720 As2 75808 O3 24192 As2 96170 H« 03830 Ba 65938 CP 34062 Ba 80987 s 19013 Ba 89549 0 10451 BaO 77586 CO2 22414 C 06198 O3 24324 BaO 59482 CrO3 40518 BaO 58564 N'-'O5 41436 2BaO 68201 P205 31799 * As many cyphers are added to the decimal fractions of the given quantity, as make up five figures after the point. 24 = Ba Barytes. Seleniate, — Sulphate, Bismuth, Chloride, — Oxide, — Sulphuret, Boracic Acid, Boron, Chloride, — Fluoride, Bromine, Chloride, Bromic Acid, Cadmium, Chloride — Oxide, — Sulphuret, Calcium, Chloride — Oxide, — Fluoride, — Sulphuret, Carbon, Chloride, — Oxide, — Sulphuret, Carbonic Acid, Chloric Acid, Chromium, Oxide, — Chloride, — Perchloride, — Sulphuret, Chromic Acid, Cobalt, Chloride — Protoxide, — Peroxide, Copper, Protochloride, — Perchloride, — Protoxide, — Peroxide, — Protoiodide, — Protosulphuret, — Persulphuret, Cyanogen, Cy2, Glucina, Gold, Protochloride — Perchloride, — Sulphuret, Hydriodic Acid, Hydrobromic Acid Hydrochloric Acid Hydrocyanic Acid Hydrofluoric Acid Hydrogen, Carburetted, 58768 BaO .54633 BaO 65628 s 13797 Bi 66707 Bi 89867 Bi 81512 B 31190 B 09289 B 16239 Br2 30812 Br2 66177 Cd 61151 Cd 87449 Cd 77597 Ca 36644 Ca 71911 Ca 52268 Ca 55999 C 25670 C 14725 c 10324 c 43323 c 15965 c 27651 CP 46958 Cr2 70109 Cr2 34635 Cr 20944 Cr2 53831 Cr 53975 Co 45462 Co 78678 Co2 71098 Cu 64130 Cu 47199 Cu2 88782 Cu 79826 Cu 33396 Cu2 79733 Cu 66296 N2 53662 G2 68846 Au2 84886 Au2 65182 Au2 80466 H2 00785 H' 01260 H2 02742 H2 03645 H2 05067 H4 24616 SeO3 .45367 SO3 34372 O4 27435 CP 33293 0 10133 s 18488 O3 68810 Cla 90711 F8 83761 CI10 69188 O5 33823 CP 38849 0 12551 s 22403 CP 63356 0 28089 F2 47732 s 44001 CI 74330 CP 85275 CP 89676 0 56677 S2 84035 O2 72349 O5 53042 0« 29891 CP 65365 CP 79056 S3 46169 O3 46025 CP 54538 0 21322 0s 28902 CI 35870 CP 52801 0 11218 0 20174 I 66604 s 20267 s 33704 C2 46338 O3 31154 CP 15114 CP 34818 S3 19534 p 99215 BrJ 98740 CP 97258 Cy2 96355 Fa 94933 C 75384 25 Hydrogen, Carbuietted, —• Phosphuretted, — Arseniuretted, ■— Peroxide, Hydrosulphuric Acid, \ Hydrogen, Sulphuretted, j Hydroselenic Acid, Hydro telluric Acid, Iodic Acid, Iodine, Chloride, Iron, Protochloride, — Perchloride, — Protoxide, — Peroxide, — Sulphuret, —- Sulphuret, Pyrites, Lead, Chloride, — Protoxide, — Peroxide, — Chromate, — Nitrate, — Phosphate, — Sulphate, — Sulphuret, Lime, — Hydrate, — Carbonate, — Phosphate, — Sulphate, = Pb = Ci = Ci = C; = c Lithia, Lithium, Chloride Magnesia, — Phosphate, — Sulphate, Magnesium, Chloride, — Sulphuret, Manganese, Protochloride — Sesquichloride, — Superchloride, — Protoxide, — Deutoxide, — Pei oxide, — Sulphate, — Sulphuret, Manganic Acid, Mercury, Protochloride __Perchloride, 68287 54646 4047 31916 29866 H4 .14036 C2 .85964 H6 08712 P2 91288 H6 03830 As2 96170 H2 05873 O2 94127 H2 05841 s 94159 H2 02461 Se 97539 H2 01524 Te 98476 I2 75942 O5 24058 I2 41627 CI10 58373 Fe 43385 CP 56615 Fe2 33813 Cl« 66187 Fe 77232 0 22768 Fe2 69338 O3 30662 Fe 62773 s 37227 Fe'2 52923 S3 47077 Fe 45744 S2 54256 Pb 74519 CP 25481 Pb 92829 0 07171 Pb 86618 O2 13382 PbO 68147 CrO3 31853 PbO 67317 N205 32683 2PbO 75761 P205 24239 PbO 73563 SO3 26437 S* 10612 O4 21101 Pb 86550 s 13450 Ca 71911 0 28089 CaO 75991 H20 24009 0 42686 H2 02668 CaO 56292 CO2 43708 C 12086 O3 47436 2CaO 44382 P205 55618 P2 24453 O7 43631 CaO 41532 SO3 58468 S 23469 O4 46665 L 44850 0 55150 L 15520 CP 84480 Mg 61293 0 38707 2MgO 36671 P20* 63329 MgO 34015 SO 8 65985 Mg 26348 CP 73652 Mg 44046 s 55954 Mn 43865 CP 56135 Mn 34252 CP 65748 Mn 20665 CP 79335 Mn 77573 0 22427 Mn2 69752 0s 30248 Mn 63363 O2 36637 MnO 47082 SO3 52918 Mn 63228 s 36772 Mn 53553 0» 46447 HgJ 85117 CP 14883 Hg 74091 CP 25909 26 — Protoxide, Hg' — Peroxide, Hg — Cyanide, . Hg Mercury, Sulphuret, Hg Molybdic Acid, Mo Nickel, Chloride, . Ni — Oxide, . Ni Nitrogen, Chloride, N2 Nitric Acid, dry, . N2 — Hydrate, sp. gr. 1.521 N205 = N2 22423 H2 Nitrous Acid, N2 Nitric Oxide, N Nitrous Oxide, W Oxalic Acid, dry, . C2 Osmic Acid, Os Phosphorous, Protochloride, P2 — Perchloride, P2 Phosphoric Acid, . P2 Phosphorous Acid, P2 Hypophosphorous Acid, P2 Platinum, Protochloride, Pt — Perchloride, Pt ■—■ Potassium-Chloride, \ —- Ammonium-Chloride, \ Pt KCP Pt N2H« Potassium, Chloride, K — Iodide, K — Sulphuret, K Potash, K — Hydrate, K 69749 O2 —- Carbonate, KO = K 56549 C — Chlorate, KO = K 31967 CP — Nitrate, . KO = K 38669 N2 — Sulphate. KO = K 44902 S Selenic Acid, Se Silica, Si Silicon, Chloride, . Si — Fluoride, Si — Sulphuret, Si Silver, Bromide, . Ag — Chloride, . Ag — Cyanide, . Ag — Iodide, Ag Silver, Nitrate, AgO — Oxide, Ag — Phosphate, 2AgO — Sulphuret, Ag .96200 92678 79325 86287 66612 45508 78709 11763 26149 85753 01581 37112 46955 63904 33757 75672 22805 15057 43966 56667 79688 73587 58212 40420 30563 44232 07692 52534 23674 70891 83048 28474 68092 08823 38492 28883 46562 13973 54067 18437 62244 48050 17284 28347 31497 58011 75330 80380 46132 68194 93111 76490 87045 O O Cy» S o8 CP 0 CP O6 Aq O6 0s 0 0 0s O4 CP CI10 O5 0s 0 CP CI* ► ci* .03800 07322 20675 13713 33388 54492 21291 88237 73851 14247 75996 62888 53045 36096 66243 24328 77195 84943 56034 43333 20312 26413 41788 29015 H2C16 48076 CP P S 0 H2 CO2 0s CPO5 0« N205 O6 SO3 0* O3 O3 CP F6 S3 Br2 CP Cy2 I2 N2Os O P2Os s 47466 76326 29109 16952 01777 31908 34628 61508 39150 53438 47358 45933 36661 37756 51950 82716 71653 68503 41989 24670 19620 53868 31806 06889 23510 12955 27 Soda, — Hydrate, Na 57789 — Carbonate, Na 43591 Carbonate, cryst., — Sulphate, anhydrous, = Na 32609 — Sulphate, cryst., Sodium, Chloride, . . — Fluoride, .... — Fluo-Silicide, .... — Sulphuret, .... Strontian, . — Carbonate, .... — Nitrate, ..... — Sulphate, .... Strontium, Chloride, Sulphuretted, Hydrogen, Sulphurous Acid, Hyposulphurous Acid, . Sulphuric Acid, anhydrous, — Hydrate, sp gr. 1.85 = S 33782 Hyposulphuric Acid, Sulphur, Chloride, SCI — — . SCP — . . SCP Telluric Acid, .... Tellurium, Sulphuret, Tantalic Acid, .... Tantalum, Chloride, — Oxide, ..... Tin, Protochloride, . . — Perchloride, .... — Protoxide, .... — Peroxide, .... — Sulphuret, .... Titanic Acid, .... Titanium, Chloride, Tungstic Acid, .... Uranium, Protoxide, — Peroxide, Vanadium, Suboxide, — Oxide, . Vanadic Acid, . Water, ... Yttria, ... Zinc, Chloride, .... — Oxide, ..... — Sulphuret, .... Zirconia, . — Sulphate, .... Na .74418 O .25582 O2 397H2 H2 02479 NaO 58576 CO2 41424 C 11454 03 44955 NaO, CO2 | 37287 Aq10 62763 NaO 43819 SO3 56181 s 22551 O* 44840 NaO, SO3 1 44231 Aq10 55769 Na 39656 CP 60344 Na 55441 F2 44559 Na3 24709 SPFis 75291 Na 59118 S 40882 Sr 84551 0 15449 SrO 70074 CO2 29926 SrO 48877 N205 51123 SrO 56360 SO3 43640 Sr 55285 CP 44715 H2 05841 s 94159 S 50145 O2 49855 ss 66796 O2 33204 s 40139 O3 59861 SO3 81670 Aq 18330 0< 65184 H2 02034 S2 44588 O* 55412 s ■47614 CI 52386 s 18516 CI4 81484 s 13156 CP 86844 Te 72780 03 27220 Te 66596 S2 33404 Ta2 88494 O3 11506 Ta2 63471 CI6 36529 Ta 92024 0 07976 Sn 62422 CP 37578 Sn 45372 CI* 54628 Sn 88028 0 11972 Sn 78616 o^ 21384 Sn 64634 s* 35366 Ti 60293 0* 39707 Ti 25542 CI* 74458 W 79773 03 20227 U 96443 0 03557 U2 94758 03 05242 V 89538 0 10462 V 81058 O2 18942 V 74045 Os 25955 H* 11111 0 88889 Y 80073 0 19927 Zn 47670 CI* 52330 Zn 80128 0 19872 Zn 66716 s 33284 Zr* 73695 0« 26305 ZnO 50103 so» 49897 DESCRIPTION OF A CHEMICAL READY-RECKONER. u -- 12 22 -L 10 20 15 30 13.5 27 11.25 22.5 Many of the calculations which the chemist finds it necessar\ to make, fall under what is commonly termed the rule of three (the rule of proportion). Calculations of that sort can be exe- cuted rapidly but roughly, for ordinary operations, by means ot a pair of compasses and ihe diagram given in thf margin. This diagram contains Gdntkr's linr nf hgometnc nnmlwrs. The compasses employed must open easily and have very fane points. If you open the compasses so wide that one leg points to 10, and the other to 20, upon this scale, you will find that wherever you apply the compasses thus opened^ to the degrees marked upon the scale, the numbers situated at their two points will always bear the relation of 10 : 20. Hence you can readily perform such calculations as the following :— 50 : 100 45 : 90 19.5 : 39 17.75 : 35.5 With any other opening of the compasses, you come to similar results : at equal intervals of space, the numbers on the scale are always proportional. Now, although such calculations cannot be made with great accuracy, and are not much to be depended upon when each term consists of more than three figures ; yet the results are sufficiently correct for many common laboratory experiments, for checking the results of direct arithmetical calculations, and for verifying the calculations contained in argumentative discourses. I shall mention a few problems in which this method of calculation can be brought into use, in company with portions of the foregoing Tables of Atomic Weights and Decimal equivalents. Problem 1. How much Sodium is contained in 27^- grains of Chloride of Sodium?—1 grain of Chloride of Sodium contains .39656 grain of Sodium. See Table, page 27. Hence the problem to be solved is this:— 100 : 39.66 : : 27.5 : .-/.-. Place o.ne leg of the compasses upon 100 at the bottom of the scale, and the other upon 39J or a little beyond 391, namely, as near to 39-^ as you can guess. Then remove one leg of the | compasses from 100 to 27£; upon which the other leg will fall 3 upon 10-j\, which is the number of grains of Sodium contained in 27^ grains of NaCl2. Proof—.39656 X 27.5 = 10.905400. Problem 2. How much Chloride of Silver is produced by 20 J grains of Silver ?—1 part of Chloride of Silver contains .7533 part of Silver. Table, page 26. Hence the problem is this :— 75.33 : 100 : : 20.5 : x. Place the two legs of the compasses upon 100 and 75J-. Then remove one leg from 75J up to 20J, upon which the other leg falls upon 271• = grains of Chloride of Silver, produced by 20| grains of Silver. 45 50 Proof. 100 X 20.5 75.33 = 27.213. 29 ON THE ANALYSIS OF SOILS. The following directions are from a paper issued from the "Museum of -Economic Geology."* In selecting specimens, care must be taken to obtain a fair average sample, and to insure the true subsoil or subjacent hard rock, clay, sand, &c. Specimens of the latter should be obtained as near as possible be- neath the spot whence the soil may have been selected, for it sometimes happens that the soil of a field varies in places from resting on different kinds of subsoil. The quantity of soil taken as a specimen should weigh about a pound, which should be tied up in a canvass bag and labeled. With respect to specimens of subsoils, if of marl, sand, or clay, por- tions weighing about a pound should be tied up in a canvass bag, labeled to correspond with the respective soils above them. If the subjacent rocks be hard, a piece also weighing about a pound, and fresh broken from the body of the rock, as nearly as possible beneath the surface whence any specimen of soil may have been selected should suffice, and should be wrapped in strong brown paper, labeled to correspond with the soil above it. I. Dry the specimen at 212° Fahr., powder, sift through a lawn sieve, rub in a mortar, again dry at 212°, and put into a stoppered bottle. II. Spread 5a0 grains on a sheet of writing paper, and expose to the air for twelve hours : note the increase of weight: from seven to ten grains is a favorable indication. III. Determine the amount of carbonic acid in 100 grains, by treating it in a counterpoised bottle with hydrochloric acid with the usual precau- tions. IV. Determine the amount of organic matter in 200 grains, by heating to redness in a platinum crucible, with occasional stirring; weigh the residue, and divide it into two equal parts: introduce one into a counter- poised bottle containing hydrochloric acid, and estimate the disengaged carbonic acid; if this be less than that obtained before calcination, the difference must be added to the weight of the calcined product under ope- ration, and this deducted from the weight before calcination will indicate the amount of organic matter. V. The other half of the residue left after calcination is now to be boiled in a flask with about an ounce of hydrochloric acid. _ By this means all the ingredients except the silica and part of the alumina will be dis- solved, some of them being decomposed. The insoluble part is to be sepa- rated by filtration, washed until no longer acid, and dried. The solution, together with the washings of the insoluble powder, is to be marked a, and put aside for further examination. The powder is to be finely pulverized and mixed with four times its weight of dried carbonate of soda; the mix- ture is then to be heated in a platinum crucible until it fuses into a glass. The crucible and its contents being placed, while warm, in a Wedgewood dish containing distilled water, about an ounce of hydrochloric acid is to be added and heat applied. More acid and water may be added if neces- until nothing more is dissolved. This being done, the solution and in- soluble part are to be evaporated to dryness, in order to aggregate the silica * Pharm. Journal, vol. iv. 30 held in suspension; and care must be taken, during this operation, that no hard lumps are left in the solution, as the silica sometimes forms a coat- ing over such particles through which the acid will not act. The residue, after the evaporation, is to be heated with water mixed with about half an ounce of hydrochloric acid, the solution is to be filtered and the insoluble part washed. The latter is the silica, which must be carefully heated to redness, and weighed while warm.* To the solution from which the silica has been separated ammonia is to be added ; the alumina is hereby pre- cipitated, which is washed, ignited, and weighed with the same precautions as the silica. VI. The solution a is now to be examined. For this purpose add am- monia in excess, and afterwards strong acetic acid in considerable excess, and bod the mixture ; phosphate of peroxide of iron and phosphate of alu- mina (if present) will be precipitated. Collect and wash the precipitate, and label the solution C. Treat the precipitate with solution of caustic potassa, which will redissolve the pltosphate of alumina, and leave the phosphate of iron ; separate, wash, dry, and weigh the latter; add am- monia to the potash solution to throw down the phosphate of alumina, which is, in like manner, to be collected and weighed. It must not be inferred that the phosphates of iron and alumina obtained in this manner existed as such in the soil; the phosphoric acid may have been, at least in part, in combination with lime and magnesia, while the iron may have been in the state of peroxide, and the alumina uneombined ; but, on dissolving these ingredients in the hydrochloric acid, the phos- phate of lime or magnesia would be decomposed, and phosphate of iron and alumina formed. As this decomposition would always take place under the circumstances indicated, it next becomes a question whether the equivalent proportions of peroxide of iron, or alumina, or of phosphoric acid existed in excess. To determine this point, divide the solution c into two parts ; to one add a few drops of solution of perchloride of iron, which, if any earthy phosphates still remain uudecomposed, will occasion a preci- pitate of phosphate of iron, in which case it may be concluded that the whole of the iron originally in the solution has been obtained in the state of phosphate of iron. Continue the addition of perchloride of iron as long as a precipitate is formed, and treat this precipitate the same as that first obtained from solution a. If, on the other hand, no precipitate be formed from the perchloride of iron, it will be necessary to try whether there be more iron or alumina in the solution. In this case, add to the other half of the solution c liquid ammonia, so as to render it slighly alkaline; then add hydrosulphuret of ammonia, which will throw down peroxide of iron, oxide of manganese and alumina, if present; collect and wash this precipi- tate, and label the solution d. Dissolve the precipitate in hydrochloric acid and boil the solution, add caustic potassa in excess, which will throw down peroxide of iron and oxide of manganese, but will retain alumina in solution; the two former being thus separated, add hydrochloric acid to the filtered solution in slight excess, and finally precipitate the alumina by ammonia. VII. The quantity of manganese contained in soils is usually so small as to render its separation from the iron unnecessary. Its presence may be * Or raiher the crucible should be allowed to cool underneath a receiver close to a vessel containing sulphuric acid, and weighed with the cover on. 31 exr.n ^ by the black color whichl the iron precipitate assumes on being :ni. 7 t0 the air- or hy the smell of chlorine, which is afforded on add- ing a tew drops of hydrochloric acid to the precipitate. If thought desira- we to separate the two oxides, dissolve them in hydrochloric acid and add precipitated carbonate of lime, which will throw down the oxide of iron Separate the precipitate, and add to the filtrate ammonia and oxalate of ammonia, by which the lime is removed ; then add caustic soda. Collect dry, and weigh the precipitate, which may be estimated as oxide of man- ganese. VIII. The solution d may still contain lime, magnesia, and salts of potassa and soda. Boil, to drive off any sulphuretted hydrogen which it may contain, then add oxalate of ammonia as long as a precipitate of oxalate of lime is formed. Collect, dry, and weigh this precipitate, and label the solution e ; if the precipitate be dried at 212°, it will contain one atom of water. IX. Add hydrochloric acid to the solution e ; evaporate to dryness, and heat to dull redness. Redissolve in water, and add red oxide of mer- cury ; treat the residue with water, pure magnesia (if present) will re- main, which is to be collected and weighed. X. The chlorides of potassium and sodium, as well as the sulphate of lime, have yet to be determined. Boil 200 grains of the dried specimen in ten ounces of distilled water; filter the solution and wash the insoluble part; divide the solution into two equal parts; to one add nitric acid, and then chloride of barium as long as any precipitate occurs. Collect, wash, and dry this precipitate, which is sulphate of baryta, obtained from the decomposition of sulphate of lime. To the other half of the solution add nitric acid, and then nitrate of silver as long as any precipitate occurs, which treat as in the former case. This will be chloride of silver, obtained from the decomposition of the chlorides of potassium and sodium. The above process, though it has no pretensions perhaps to great accu- racy, is sufficiently exact for most practical purposes. When a complete analysis is to be made, Dr. Ure adopts the following method.* A known weight (about 100 grains) of the soil is introduced into a large glass flask with a thin concave bottom, capable of holding at least a quart of water, and over it is poured a sufficient quantity of dilute hydrochloric acid. The flask is placed on the ring of a retort-stand and exposed to a gentle heat, while the beak of a large glass funnel, having its mouth covered with a porcelain basin filled with distilled water, is inserted into its neck. By this arrangement, a continuous ebullition may be maintained in the mix- ture of soil and acid, without loss of acid or nuisance from its fumes, be- cause the vapors are condensed whenever they reach the cold basin above the funnel; and in this way a boiling heat may be kept up till every con- stituent of the soil, except the silica, becomes dissolved. The funnel and porcelain basin should be properly supported on the rings of the retort- stand Br Ure maintains the action for six or eight hours, at the end of which time he throws the contents of the matrass on a filter, and super- saturates the filtered liquor with ammonia The silica which remains on thffiUer having been washed, is dried and weighed. The alumina, oxide of iron andphosplwte oj lime thrown down by the monia being washed on the filter, and dried to a cheesy consistence, are * Pharm. Journ.,"June, 1845. 32 removed with a bone spatula into a silver basin, and digested with ™at m a solution of pure potassa, whereby the alumina is dissolved ; the alka 1 ^ solution is passed through a filter and saturated with hydrochloric aeia , ammonia is then added, pure white alumina falls, which is collected on a filter, washed, ignited and weighed. . . The iron and phosphate of lime on the filter may be dried, gently ig- nited and weighed, or otherwise directly separated from each other with- out that step, by the action of dilute alcohol, acidulated with sulphuric acid at a gentle heat. Thus the oxide of iron will be dissolved and its solution may be passed through a filter, while the sulphate of Ixme will remain undissolved, and may be dried, ignited and weighed; fire parts of it correspond with four of phosphate. The iron is obtained in the state of sesquioxide by precipitation with ammonia. The first filtered liquor, with excess of ammonia, contains the carbonate of lime and the magnesia. The former is separated by solution of oxalate of ammonia, and digestion, at a gentle heat, for a few hours; it is then filtered, washed, dried and gently ignited, by which it is converted into carbonate, in which form it is weighed. The magnesia in the filtrate is precipitated with phosphate of soda. For some refractory soils in which the alumina exists as a double or triple silicate, it becomes necessary to fuse about fifty grains of the sample in fine powder, mixed with four times its weight of dry carbonate of soda, the mixture being put into a platinum crucible, and into a cavity in the centre fifty grains of hydrate of potassa being laid. The crucible is slowly raised to a red white heat, when its contents fuse into a homogenous liquid, of a gray or brown color, according to the metals present in it. Manganese gives a purple tint, and iron a red brown. The fused matter should be poured out into a shallow platinum basin, and, as soon as it is cold, it should be pulverized, dissolved in dilute hydrochloric acid, the solution evaporated to dryness, the dry mass again digested with hot water acidulated with hydrochloric acid, and the whole thrown down upon a fil- ter. Pure silica remains, which is washed, dried, ignited and weighed. The filtered liquor, which contains the remaining constituents of the soil, is treated as already described. Besides these systematic investigations, Dr. Ure directs researches to be made for certain peculiar substances, and especially for the so-called neutro-saline constituents, in the following manner. One hundred grains of the soil are triturated with twenty times their weight of distilled water, placed in a beaker till the clayey matter subsides, and the clear liquor is then decanted into a filter. A little of the filtered solution should be test- ed with nitrate of baryta, and also with oxalate of ammonia. If precipi- tates are afforded, the presence of sulphate of lime is indicated, and the following steps must be taken to eliminate it entirely:—Two hundred grains of the soil are triturated with a quart of distilled water, holding in solution fifty grains of sal ammoniac. The mixture should be allowed to clarify itself by subsidence, when the supernatant clear liquor should be evaporated down to two ounce measures, and then mixed with an equal bulk of strong whisky (11 per cent, over proof). The whole of the sul- phate of lime will then be separated from the fluid, and, after being drained on a filter, may be dried, ignited, and weighed. For determining the alhdine salts, the water filtered from the one hun- dred grains of soil should be evaporated down to one-fifth of its bulk, and 33 en treated, 1st, with nitrate of baryta for the sulphates ; 2d, with nitrate ot silver for the chlorides ; 3d, with oxalate of ammonia for the nitrate of txme or chloride of calcium, provided no sulphate of lime is indicated by the first test; 4th, with litmus paper for the alkaline or acid reaction ; 5th, with soda chloride of platinum for potassa, salts which are very valu- able for the vigorous growth of many plants. The portions of the soil tested for potassa salts should, before being digested in water, be gently calcined, to ensure the expulsion of every particle of ammoniacal salt; otherwise the precipitate afforded by soda chloride of platinum would be fallacious. Another peculiar research to which Dr. Ure directs especial attention, is that which determines the amount of ammonia in a soil, which may ex- ist either ready formed, or in its elements, capable of affording a portion of that azotic food so indispensable to vigorous vegetation. The actual ammonia is easily obtained, by distilling the soil along with milk of lime ; the distillate will contain all the volatile alkali, which may be estimated by a standard solution of sulphuric acid, according to Peligofs method, described page 468 "Nbad's Chemical Analysis." What Dr. Ure calls the potential ammonia, slumbering, so to speak, in its embryo elements, may be estimated by igniting 200 grains of the soil with its own weight of a mixture of hydrate of soda and quicklime. Dr. Ure gives also the following simple method of testing for phosphoric acid in a soil:—Digest it for an hour or so, at a moderate heat, with di- lute nitric acid (free from hydrochloric acid). Throw the mixture on a filter; to the filtered liquor add potassa water cautiously, till the instant that a precipitate begins to appear; then drop into it a weak solution of nitrate of silver. If any phosphoric salts be present, a yellowish precipi- tate will immediately fall, which is resoluble in an excess of nitric acid. Whatever is not thus dissolved is chloride of silver, and ought to be sepa- rated by filtration. On adding then weak potassa water cautiously to the filtered liquor, pure phosphate of silver will be obtained, without any alu- mina or iron, provided the liquor be still acidulous in a slight degree. The portion of soil should be fresh, not calcined, because the phosphates, when ignited, afford a white precipitate with nitrate of silver. The stronger the solution of the phosphoric compound is, the more characteris- tic is the yellow precipitate with silver; and then ammonia may be used to effect the partial separation of the excess of acid. A solution of sxdphate of magnesia, containing a little sal ammoniac, is probably the best test liquor for detecting phosphates in faintly acidulous, but still better in neutral, solutions. The determination of phosphoric acid in soils is best effected by the following process, proposed originally by Schidze, and modified bjDiebig. It is founded on the insolubility of phosphate of peroxide of iron and phos- phate of alumina in acetic acid :—The hydrochloric solution of the soil is evaporated to dryness, nitric acid being added during the evaporation, the dry mass is treated with dilute hydrochloric acid, and the solution filtered off from the insoluble silica. To the acid solution ammonia is added, and then acetic acid ; the mixture is boiled, filtered while hot, and the precipi- tate which contains the whole of the phosphoric acid, in combination with iron and alumina, is collected on a filter, washed, dried, weighed, and di- gested with caustic potassa, which dissolves the latter. This is the pro- g 6 34 ocss as originally proposed by Schuh.e. According to Ltelag's modifica- tion,* ammonia is added to the hydrochloric solution of the soil, till a precipitate begins to form; acetic acid is then added, and, finally, acetate of soda in excess; the mixture is boiled and filtered. The precipitate, having been washed with hot water, is dissolved in hydrochloric acid, am- monia added to alkaline reaction, and then hydrosulphuret of ammonia. The fluid is filtered off from the precipitated sulphuret of iron, and the latter is washed with water mixed with hydrosulphuret of ammonia. The filtrate is concentrated by evaporation, sulphate of magnesia added, and the mixture stirred; the formation of a crystalline precipitate indicates phosphoric acid; this precipitate consists of basic phosphate of magnesia and ammonia. It is collected on a filter, washed with water containing a little ammonia, dried, and ignited; the phosphoric acid is estimated as pyrophosphate of magnesia. According to Mr. JVesbitf this process is inapplicable where phosphate of alumina is contained in the solution, the phosphoric acid being kept back in the precipitate formed by ammonia and hydrosulphuret of ammo- nia, and cannot be obtained in the filtrate. Although the quantity of soluble saline matter extracted from a mode- rate quantity of any of our soils is rarely so great as to admit of a rigor- ous quantitative examination, it is, nevertheless, very desirable that a qualitative analysis of the aqueous extract should be made, in order to furnish information as to the ingredients which are supplied directly to the plant with the water which they imbibe from the soil. In some soils, those, for instance, of Egypt and India, and of other warm countries, soluble saline matter in the form of chlorides, sulphates, and nitrates, to the amount of 14 per cent., has been found.J The qualitative examina- tion will always inform the operator whether or not a quantitative analysis is required. The most convenient plan, therefore, is to digest a large quantity (from two to three pounds) of the soil with distilled water, and, having thrown it on a moist filter and thoroughly washed the insoluble matter, to divide the filtrate into two parts, using one part for the qualita- tive, and setting aside the other for the quantitative examination, should such be found necessary. As the analysis of soils is a subject which is likely early to occupy the attention of the student in analytical chemistry, we have, with a view of assisting him in his labors, collected in a tabular form the different steps of the treatment of the hydrochloric solution. The substance of this Table is taken from the article on'the analysis of soils, in Johnstone's Agricul- tural Chemistry, a work which we take the liberty of strongly recommend- ing to the attention of the agricultural student. * Fresenius—Quantitative Analysis, p. 516. f Quarterly Journ. of the Chemical Society, No. 1, p. 45. % See Johnstone's Lectures on Agricultural Chemistry and Geology, p. 43 Ap- pendix. ALPHABETICAL TABLE OF BEHAVIOUR UNDER BLOWPIPE EXAMINATION. Name of Substance. Behaviour. Name of Substance. Behavior. 1. Alumina. Blue with nitrate of cobalt. 19. Mercury, protox- ide of. Mixed with soda and heated in a tube the metal sublimes. 2. Antimony, oxideiWith soda in deoxidizing flame, reduced and gives off white of. 1 fumes of oxide. 20. Mercury, perox- ide of. As the protoxide^ 3. Baryta. 21. Molybdenum, ox ide of. With microcosmic salt in outer flame a green glass. 4. Bismuth, oxide of With soda on charcoal reduced; brittle bead of metal. With soda on charcoal reduced, and metal volatilized, leaves 5. Cadmium, oxide of | a reddish-brown deposit. 22. Nickel, oxide of. With soda on charcoaL, reduced to a magnetic powder. With borax and mic. salt in outer flame a red glass, becoming colorless on cooling 6. Calcium (Lime). Radiates a brilliant light. Gives a red color to the flame. 23. Osmium, deutox- ide of. Osmium is characterized by forming, when heated in the air, a suboxide, which is volatile, and has a very disagree able smell, causing much inconvenience to eyes and nose. 7 Chromium, oxidei of.______________Emerald-green with fluxes. 24. Palladium, pro toxide of. Reduced. 8. Cobalt, oxide of, Blue glass, with borax in both flames. 9. Copper, oxide of. With soda on charcoal reduced. With borax and mic. salt in outer flame, green; in inner flame red. 10. Glucina. With nitrate of cobalt, dark-gray or black. 11. Gold, teroxide of, 12. Iridium, sesqui- oxide of. 13. Iron, protoxide of 14. Iron, peroxide of 15. Lead, oxide of. 16. Lithia. 17. Magnesia. 18. Manganese, pro- toxide of. 25. Platinum, oxide Reduced. 26. Potash. Violet flame. 27. Rhodium, sesqui- oxide of. Reduced. 28. Silver, oxide of. Reduced. Reduced. 29. Soda. Yellow flame. 30. Strontia. Carmine flame. Reduced. With the fluxes in the outer flame, brownish-yellow ; in the inner flame, light-green As the protoxide. 31. Tin, protoxide of. With soda in reducing flame a malleable bead of metallic tin With soda on charcoal reduced ; yellow deposit also formed on charcoal. Gives red color to the flame. Light pink with nitrate of cobalt. Wfw?°i?a ^ gnLen h*d- With borax in outer Same an ame- tnyst bead, which loses its color in the reducing flame. 32. Tin, peroxide of. Reduced with soda. 33. Uranium, sesqui- oxide of. Yellow glass with borax. 34. Vanadium, bin- oxide of. With borax, yellow in the outer flame, in the inner brown, becoming green when cold.________________________ 35. Yttria. Nothing characteristic. 36. Zinc, oxide of. With soda on charcoal, gives a white sublimate of oxide which is yellow when hot. With nit, cobalt, green. 37. Zirconia. Bright flame. m Vi^ '& « w VjV \j* I l-'V.*'