A white crystalline solid, KHCO3, soluble in water and insoluble in ethanol; r.d. 2.17; decomposes about 120°C. It occurs naturally as calcinite and is prepared by passing carbon dioxide into saturated potassium carbonate solution. It is used in baking, soft-drinks manufacture, and in CO2 fire extinguishers. Because of its buffering capacity, it is added to some detergents and also used as a laboratory reagent.