Propionic acid

Propionic acid (systematically named propanoic acid) is a naturally occurring carboxylic acid with chemical formula CH3CH2COOH. In the pure state, it is a colorless, corrosive liquid with a pungent odor. The anion CH3CH2COO− as well as the salts and esters of propionic acid are known as propionates (or propanoates).