Carbonate Equilibrium Chain

Describes the full reversible chain of dissolved inorganic carbon species, the dominant buffer system in natural waters that governs pH stability, scale formation, acid demand, and condensate corrosion.

$$\mathrm{C}{\mathrm{O}}_2(\mathrm{g})\rightleftharpoons \mathrm{C}{\mathrm{O}}_2(\mathrm{aq})\rightleftharpoons {\mathrm{H}}_2\mathrm{C}{\mathrm{O}}_3\rightleftharpoons \mathrm{HC}{\mathrm{O}}_3^{-}+{\mathrm{H}}^{+}\rightleftharpoons \mathrm{C}{\mathrm{O}}_3^{2-}+2{\mathrm{H}}^{+}$$

Variables

Symbol	Meaning	Unit
$C{O}_2(g)$	gaseous carbon dioxide
$C{O}_2(aq)$	dissolved carbon dioxide
$H_{2}C{O}_3$	carbonic acid
$HC{O}_3^{-}$	bicarbonate ion
$C{O}_3^{2-}$	carbonate ion
$H^{+}$	hydrogen ion

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Part of The Blueprint of Water