Acetate is a salt formed by combining acetic acid with a base such as an alkali, earth, metal, nonmetal, or free radical base. "Acetate" also describes a conjugate base or ion (specifically a negatively charged ion, called an anion) usually found in aqueous solutions, and is written with the chemical formula C
2 hours
3O−
2. The neutral molecule formed by the combination of acetate charge  and positive ions (called cations) is also often called "acetate" (hence lead acetate, aluminum acetate, etc.). The simplest of these is hydrogen acetate (known as acetic acid) and its corresponding salts, esters, and polyatomic anions CH
3CO−
2, or CH
3COO−
.

Industry produces about 5 million tons of acetic acid per year, most of which is used to produce acetate, which is usually in the form of a polymer. In nature, acetate is the most common building block for biosynthesis.
When part of a salt, the formula for the acetate ion is written as CH
3CO−
2. C
2 hours
3O−
2, or CH
3COO−
. Chemists usually refer to acetate as OAc−, or less commonly, AcO−. Thus, HOAc is the symbol for acetic acid, NaOAc is the symbol for sodium acetate, and EtOAc is the symbol for ethyl acetate[1] (since Ac is the usual symbol for the acetyl group CH3CO[2][3]). The pseudo-element symbol "Ac" is also sometimes encountered in chemical formulas to denote the whole acetate ion (CH
3CO−
2).[citation needed] Not to be confused with the symbol for actinium, the first element of the actinide series; context guides disambiguation. For example, the molecular formula for sodium acetate might be abbreviated as "NaOAc" instead of "NaC2H3O2". Care should also be taken when using the OAc abbreviation to avoid confusion with peracetic acid; references to these two compounds should be avoided in the literature for the sake of clarity and to avoid translation errors.

Despite its systematic name ethanoate (/ɪˈθænoʊ.eɪt/), the common acetate is still the preferred IUPAC name. [4]