Contractions. - Kali-c. K-ca.
Present name. - Potassic Carbonate. K2Co3.
Carbonate of Potash.
Prepared by heating pure Cream of Tartar to a red heat, and then allowing the product to deliquesce slowly by exposure to moist air. The Cream of Tartar should first be moistened with a little distilled water and formed into a ball; it is then wrapped in filtering-paper and dried, after which it can be conveniently heated to bright redness on hot coals. The product is then placed in a porcelain capsule, covered with a cloth, and placed in a damp cellar for two or three weeks. Decant the dissolved salt, add distilled water, and filter, after which it may be evaporated to dryness, stirring briskly towards the close of the process.
Characters and Tests. - A white crystalline powder, alkaline and caustic to the taste, very deliquescent, readily soluble in water, but insoluble in spirit, effervescing with diluted Hydrochloric Acid, and forming a solution with which Perchloride of Platinum gives a yellow precipitate. Loses about 16 per cent. of its weight when exposed to a red heat in a platinum spoon. When super-saturated with Nitric Acid, and evaporated to dryness, the residue is almost entirely soluble in water, only a little Silica remaining undissolved; and the solution is not precipitated by Chloride of Barium or Nitrate of Silver. 83 grains require for neutralization at least 980 grain measures of the volumetric solution of Oxalic Acid.
Preparations. - Solution in distilled water for P. Trituration.
Distilled water to which 5 per cent. of rectified spirit has been added is used for 1; 3s is prepared with proof spirit, 2 with 20 O.P., and all above with rectified spirit.
Reference to Horn. Proving. - Chr. Kr., iv.
Proper forms for dispensing. - lx to 3X, Solution. lx to 3, Trituration. 2 and upwards, Tincture, Pilules, or Globules.