The acetic acid/acetate buffer system is a common buffer used in the laboratory. Write the equilibrium equation for the acetic acid/acetate buffer system. The formula of acetic acid is CH3CO2H.

CH₃CO₂H + H₂O ⇄ CH₃CO₂⁻ + H₃O⁺

Explanation:

A buffer is defined as the mixture of a weak acid and its conjugate base or vice versa.

For the acetic acid buffer, CH₃CO₂H is the weak acid and its conjugate base is the ion without H⁺, that is CH₃CO₂⁻. The equilibrium equation in water knowing this is:

CH₃CO₂H + H₂O ⇄ CH₃CO₂⁻ + H₃O⁺

In the equilibrium, the acid is dissociated in the conjugate base and the hydronium ion.