Potassium hydrogen oxalate, also known as potassium bioxalate, is a salt with formula KHC2O4 or K+·HO2C-CO2-. It is one of the most common salts of the hydrogenoxalate anion, and can be obtained by reacting potassium hydroxide with oxalic acid in 1:1 mole ratio.
The salt is also known as potassium hydrogen oxalate , acid potassium oxalate, or monobasic potassium oxalate. In older literature, it was also called sorrel salt, sal acetosella ,
Potassium hydrogen oxalate occurs in some plants, notably sorrel. It is a commercial product, used in photography, marble grinding, and to remove ink stains.
