ISBN: 9781235877476

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not … Plus…

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1896 edition. Excerpt: ... Tin reacts with hydrochloric acid to form stannous chloride, SnCl2. With nitro-hydrochloric acid containing an excess of hydrochloric acid, stannic chloride, SnCh., is obtained. Solutions of these salts are useful for laboratory practice. Some of the compounds of tin follow:--() Stannic Acid, H2Sn08, is obtained when calcium carbonate is treated with an excess of stannic chloride. Sodium Stannate, Na2Sn03, is largely used as a preparing salt in calico-printing. (6) Stannous Sulphide, SnS, is a brown substance, while Stannic Sulphide, SnS2, is a yellow one. These precipitates are produced in the regular course of analysis when the solution contains the corresponding salts of tin. They are soluble in yellow ammonium sulphide. 141. Tests for Tin.--1. Metallic tin is recognized by its lustre and by the emission of a crackling sound when bent or bitten. 2. Any solid containing tin, or metallic tin itself, when heated on charcoal in the oxidizing flame, gives a coating around the assay which is pale yellow while hot and white when cold. 3. A solid may be tested by dissolving in hydrochloric acid and then adding a solution of mercuric chloride. At first a white precipitate, Hg2Cl2, is obtained. This soon turns black, metallic mercury being set free. See Art. 130, 3. BISMUTH. 142. Occurrence and Preparation.--Bismuth usually occurs native, but it is always contaminated with a small percentage of other metals. Its chief ores are bismuth ochre, Bi20s, and bismuthite, Bi2S3. Exp. 89. Make a pellet of any bismuth compound with sodium carbonate and a drop of water. Heat this pellet on charcoal in the reducing flame, and test the bead obtained, as usual. Then heat the bead in the oxidizing flame, and note the coating, Bi203, which is formed... James Henry Shepard, Books, History, Elements of chemistry, descriptive and qualitative Books>History <