[899] Ibid., 1877.
[900] Ann. Chem. Pharm., vol. cv. p. 245.
4. SILVER.
§ 819. Silver = 108; specific gravity, 10·5; fusing-point, 1023° (1873° F.).—Silver, as separated in analysis, is either a very white, glittering, metallic bead, or a dull grey powder. It does not lose weight on ignition, and is soluble in dilute nitric acid.
§ 820. Chloride of Silver, AgCl = 143·5; specific gravity, 5·552; Ag, 75·27 per cent., Cl, 24·73 per cent., is a dense, white, curdy precipitate, when produced in the wet way. It is very insoluble in water, dilute nitric acid, and dilute sulphuric acid; in many warm solutions (especially aqueous solutions of the chlorides generally), the alkaline and alkaline-earthy nitrates, and tartaric acid solutions, the silver is dissolved to an appreciable extent, but deposited again on diluting and cooling. The complete solvents of chloride of silver are—ammonia, cyanide of potassium, and hyposulphite of soda. Chloride of silver cannot be fused at a high heat without some slight loss by volatilisation; on coal in the R.F., it fuses very easily to a globule. It can with soda be reduced to metal, and can also readily be reduced by ignition in a current of hydrogen, carbon oxide, or carburetted hydrogen gas.
§ 821. Sulphide of Silver, Ag2S = 248; specific gravity, 7·2; Ag, 87·1 per cent., S, 12·9 per cent., when prepared in the wet way, is a black precipitate, insoluble in water, dilute acids, and alkaline sulphides. If ignited in hydrogen it may be reduced to the metallic state; it is soluble in nitric acid, with separation of sulphur.
§ 822. Preparations of Silver used in Medicine and the Arts.
(1) Medicinal Preparations:—