Sebanyak 2,0 liter larutan CH3COOH 0,2 M dicampur dengan 1,0 liter larutan CH3COONa 0,1 M. Bila harga Ka = 10pangkat -5 , maka pH larutan buffer yang terbentuk

Dik :
Volume CH3COOH = 2L
Volume Ch3COONa = 1L
Molaritas CH3COOH = 0,2
Molaritas CH3COONa = 0,1
Ka = 10^-5

Dit :
pH = ?

Jawab :
mmol = V x M
= 2 x 0,2
= 0,4mmol/1000
= 4.10^-4mol
mmol = V x M
= 1 x 0,1
= 0,1mmol/1000
= 10^-4
[H+] = Ka x mol asam/ mol garam
= 10^-5 x 4.10^-4/ 10^-4
= 4.10^-5
pH = - log [H+]
= - log 4.10^-5
= 5 - log 4
Mohon maaf apabila salah