K2O

K2O, or potassium oxide, is an inorganic compound and the anhydrous oxide of potassium. It appears as a white, highly hygroscopic solid. On contact with water it reacts vigorously to form potassium hydroxide: K2O + H2O → 2 KOH. In air it readily absorbs moisture and carbon dioxide, converting to hydroxide- and carbonate-containing species.

Physically, potassium oxide is a dense white solid with strong basic character. It is highly reactive with water, and its dissolution in water is highly exothermic. It reacts with acids to give corresponding potassium salts (for example K2O + 2 HCl → 2 KCl + H2O).

Occurrence and production: Free K2O is not common in nature; it is encountered mainly as the oxide equivalent in potassium-bearing minerals and silicates. Industrially, K2O is produced by dehydration of potassium compounds at high temperature, for example calcining K2CO3 or KOH to remove water or carbon dioxide.

Uses: K2O is used as a flux in the glass and ceramic industries, where it promotes melting and modifies viscosity. It also serves as a precursor to other potassium compounds and a basic reagent in synthesis. Handling requires dry, inert conditions; it is highly caustic and reacts violently with water, so protective equipment and strict moisture control are essential.