Potassium bisulfate

Potassium bisulfate is the potassium salt of bisulfate anion, with the molecular formula KHSO4. This compound is commonly used in the conversion of tartrates to bitartrates in wine. Potassium bisulfate is also used as a disintegrating agent in analytical chemistry.

A solution of potassium bisulfate behaves as if the two related compounds (K2SO4 and H2SO4) were side by side uncombined. Adding ethanol to a solution of potassium bisulfate precipitates out sulfate.