Prep. 1. Solid, anhydrous:—
a. Pure commercial tersulphide of antimony, in coarse powder, 1 part; concentrated hydrochloric acid, 5 parts; are mixed in a capacious stoneware or glass vessel set under a chimney with a quick draught, to convey away the fumes, the whole being constantly stirred, and, as the effervescence slackens, a gradually increasing gentle heat applied until solution is complete; the resulting liquid is put into a retort, and distilled, until each drop of the distillate, as it falls into the aqueous liquid which has previously passed over into the receiver, produces a copious white precipitate; the receiver is then changed, and the distillation continued, when pure TRICHLORIDE OF ANTIMONY passes over, and solidifies on cooling to a white and highly crystalline mass, which must be carefully excluded from the air.
b. From pure metallic antimony, 2 parts; bichloride of mercury, 5 parts; both in fine powder; mixed and distilled in a retort with a large neck, by a gentle sand-heat, into a suitable receiver. Chemically pure.
2. Liquid:—
a. (Liquor antimonii chloridi, B. P.) Syn. Solution of chloride of antimony.
Prep. Take of black antimony, 1 lb.; hydrochloric acid, 4 pints; place the black antimony in a porcelain vessel; pour upon it the hydrochloric acid, and, constantly stirring, apply to the mixture, beneath a flue with a good draught, a gentle heat, which must be gradually augmented as the evolution of gas begins to slacken, until the liquid boils. Maintain it at this temperature for fifteen minutes; then remove the vessel from the fire, and filter the liquid through calico into another vessel, returning what passes through first, that a perfectly clear solution may be obtained. Boil this down to the bulk of two pints, and preserve it in a stoppered bottle.
Characters and Tests. A heavy liquid, usually of a yellowish-red colour. A little of it dropped into water gives a white precipitate, and the filtered solution lets fall a copious deposit on the addition of nitrate of silver. If the white precipitate formed by water be treated with sulphuretted hydrogen it becomes orange-coloured. The specific gravity of the solution is 1·47. One fluid drachm of it mixed with a solution of a quarter of an ounce of tartaric acid in four fluid ounces of water, forms a clear solution, which, if treated with sulphuretted hydrogen, gives an orange precipitate,
weighing, when washed and dried at 212°, at least 22 grains.
b. (Commercial.)—a. Take of ash or calx of antimony, 31⁄4 lbs.; common salt, 2 lbs.; oil of vitriol, 11⁄2 lb.; water, 1 lb.; proceed as before. Prod., 21⁄2 lbs.
c. From roasted sulphide or glass of antimony, 7 lbs.; salt, 28 lbs.; oil of vitriol, 21 lbs.; water, 14 lbs.; as before.