Potassium hydroxide

Potassium hydroxide is a chemical compound. The chemical formula is KOH. It has potassium and hydroxide ions.

Properties
It is a white powder. It dissolves easily in water to make a basic solution. It is corrosive to skin. It reacts with acids to give potassium salts. It is less common than sodium hydroxide. About 700,000 tons are made each year. It is hygroscopic, meaning that it absorbs water from the air and forms a solution. It is very hard to get the water out again. It releases heat when it is dissolved in water, similar to sodium hydroxide. It gradually reacts with carbon dioxide in the air to form potassium bicarbonate. It melts easily. It feels greasy when it gets on the skin because it makes soap from the fat in your skin. It is made when potassium reacts with water.

Preparation
It is made by electrolysis of a potassium chloride solution. It can also be made by reacting calcium hydroxide solution (limewater or slaked lime) with potassium carbonate. The calcium carbonate precipitates and is filtered, leaving potassium hydroxide in solution.

Uses
It is used to make soap. It is also used in organic chemistry. It can be used to make fertilizers and other potassium compounds. It is used to make diesel from plants. It is used in alkaline cells and nicads as an electrolyte. It can be used to identify mushrooms.

Related pages
Lithium hydroxide
Sodium hydroxide

Category:Potassium compounds
Category:Hydroxides