What is Potassium aluminium sulfate?
[[File:Alum.jpg|thumb|Potassium aluminium sulfate]] '''Potassium aluminium sulfate''', or '''potash alum''', or '''potassium alum''', is a [[chemical compound]]. Its chemical formula is KAl(SO<sub>4</sub>)<sub>2</sub>. It contains [[potassium]], [[aluminium]], and [[sulfate]] [[ion]]s. Crystals of it are transparent, and it is white when made into a powder. ==Properties== It is a [[acid]]ic solid at room temperature. It does not have a colour; its crystals are transparent, and its powder is white. It reacts with [[sodium bicarbonate]] to make [[carbon dioxide]] gas. It exists naturally, and can be found as a [[mineral]]. ==Preparation== It is made by reacting [[aluminium sulfate]] with [[potassium sulfate]]. ==Uses== It is used to purify water. It is also used in [[deodorant]]s. It is an [[antiseptic]]. It had several uses in the past, such as in dyeing clothes. Crystals can be grown from a solution of potassium aluminium sulfate. ==Related pages== *[[Alum]] *[[Aluminium sulphate]] {{chem-stub}} [[Category:Potassium compounds]] [[Category:Aluminium compounds]] [[Category:Sulfur compounds]]