Buffer Solutions

Solutions that resist changes in their pH, even when small amounts of acid or base are added.

Acidic Buffer

A common solution for an acidic buffer is ethanoic acid (CH₃COOH) and sodium ethanoate (NaCH₃COO). The ethanoic acid acts as the weak acid (CH₃COO^-) and the sodium ethanoate forms the conjugate base (Na⁺ CH₃COO^-).

Alkaline Buffer

A common solution for an alkaline buffer is ammonium chloride (NH₄Cl) and ammonia (NH₃). The ammonium chloride acts as source of the weak acid NH₄⁺ and the ammonia acts as the conjugate base.

See also: Acid, Base.