FS Foreign Trade Acetate is a negative ion, or anion, typically found in aqueous solution. It is often written with the chemical formula C2H3O2−. The neutral molecules formed by the combination of the acetate ion and a positive ion (or cation) are also commonly called “acetates”. The simplest of these is hydrogen acetate, or acetic acid, with corresponding salts, esters, and the polyatomic anion CH3CO2−, or CH3COO− Most of the approximately 5 billion kilograms of acetic acid produced annually in industry are used in the production of acetates, which usually take the form of polymers. In nature, acetate is the most common building block for biosynthesis. For example, the fatty acids are produced by connecting the two carbon atoms from acetate to a growing fatty acid.