potassium carbonate(redirected from Carbonate of potash)
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potassium carbonate,chemical compound, K2CO3, white, crystalline, deliquescent substance that forms a strongly alkaline water solution. It is available commercially as a white, granular powder commonly called potash, or pearl ash. It was originally obtained from wood ashes or from the residue left in pots after certain plants, e.g., kelp, were burned in them. It is prepared commercially chiefly by electrolysis of potassium chloride to form potassium hydroxide, which is then carbonated (e.g., by adding carbon dioxide gas). It is used in the manufacture of soft soaps and glass, for washing wool, and in the production of other potassium compounds.
, potash, K2C03, a salt; colorless crystals. Density 2.3 g/cm3; melting point, 89.4°C. Highly hygroscopic; solubility, 113.5 g per 100 g H2O at 20°C (156 g at 100°C). The solution is alkaline.
Potash has been extracted from the ashes of wood and herbaceous plants since ancient times. It is produced commercially mainly from natural potassium salts and as a by-product of the conversion of nepheline to aluminum oxide. Potassium carbonate is used in the preparation of liquid soaps, hard and crystal glasses, dyes, and photographic materials. It is also used as apotassium fertilizer.