Hitunglah pH larutan CH3COOH 0,05 M dengan Ka = 1,8×10^-5 !

CH3COOH -> CH3COO^- + H^+
[H+] = √ ka × Ma
= √ 1,8×10^-5 × 5.10^-2
= √ 9.10^-7
= 3.10^-3,5

pH = - log [H+]
= -log 3.10^-3,5
= 3,5 -log 3

:)))))