|IUPAC name||Potassium carbonate|
|Other names||Potash, pearlash|
|Molar mass||138.2055 g/mol|
|Appearance||White deliquescent solid|
|Density||2.29 g/cm3, solid|
|Solubility in water||112 g/100 mL (20 °C)|
|Flash point||Not flammable|
|Other cations||Lithium carbonate, sodium carbonate, caesium carbonate|
|Except where noted otherwise, data are given for|
materials in their standard state
(at 25 °C, 100 kPa)
Infobox disclaimer and references
Potassium carbonate is a white salt, soluble in water (insoluble in alcohol), which forms a strongly alkaline solution. It can be made as the product of potassium hydroxide's absorbent reaction with carbon dioxide. It is deliquescent, often appearing a damp or wet solid. Potassium carbonate is used in the production of soap and glass.
Potassium carbonate was first identified in 1742 by Antonio Campanella and is the primary component of potash and the more refined pearlash or salts of tartar. Historically pearlash was created by baking potash in a kiln to remove impurities. The fine white powder remaining was the pearlash. The first patent issued by the U.S. Patent Office was awarded to Samuel Hopkins in 1790 for an improved method of making pearlash.
Other terms for potassium carbonate:
- Carbonate of potash
- Dipotassium carbonate
- Dipotassium salt
- Pearl ash
- Salt of tartar
- Salt of wormwood
Today potassium carbonate is prepared commercially by the electrolysis of potassium chloride. The resulting potassium hydroxide is then carbonated using carbon dioxide to form potassium carbonate, which is often used to produce other potassium compounds.
- 2KOH + CO2 → K2CO3 + H2O
Mixed with water it causes an exothermic reaction that results in a temperature change, producing heat.
In cuisine, it is used as an ingredient in the production of grass jelly, a food consumed in Chinese and Southeast Asian cuisines.