The extensive acid electricity of intact carbonic acid suggests that it is an essential protonation agent below physiological conditions.
The carbonate ion (CO32−) is a strong base. It is a conjugate base of the weakly acidic bicarbonate (IUPAC name hydrogen carbonate HCO3−), itself a strong conjugate base of the still weakly acidic carbonic acid.
Carbonates are moderately strong bases. Aqueous solutions are basic because the carbonate anion can accept a hydrogen ion from water. CO32− + H2O ⇌ HCO3− + OH− Carbonates react with acids, forming salts of the metal, gaseous carbon dioxide, and water.
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