Carbonate

Carbonate is a compound ion with a charge of -2 and an elemental formula of CO₃^2-. An aqueous solution of carbon dioxide contains a minute amount of H₂CO₃, called carbonic acid, which dissociates to form hydrogen ions and carbonate ions. It would be a fairly strong acid if carbonic acid existed in pure form, but the equilibrium favors carbon dioxide and so such solutions are fairly weak. In biological systems the enzyme [carbonic anyhdrase]? catalyzes this interconversion between carbon dioxide and carbonate ions.

Carbonate-containing salts are industrially and minerologically ubiquitous. The term "carbonate" is also commonly used to refer to one of these salts.

The term is also used as a verb, to describe the process of raising carbonate and bicarbonate concentrations in water, see also [carbonated water]?, either by the introduction under pressure of carbon dioxide gas into the water, or by dissoving carbonate or bicarbonate salts into the water.