100 mL CH3COOH 0,2 M dengan 100 mL NaOH 0,2 M

CH3COOH + NaOH → CH3COONa + H2O

→ CH3COOH
m = 0,2 x 100 = 20
r = 20
s = -

→ NaOH 
m = 0,2 x 100 = 20
r = 20
s = -

→ CH3COONa
m = -
r = 20
s = 20

M = n / v
M = 20/100 + 100
M = 20 / 200
M = 1/10
M = 0,1M

→ H2O
m = -
r = 20
s = 20

[OH-] = √kw/ka . [anion]garam
[OH-] = √10^-14/10^-5 . 1 x10^-1
[OH-] = √10^-9 . 10^-1
[OH-] = √10^-10
[OH-] = 10^-5

pOH = -log [OH-]
pOH = -log 10^-5
pOH = 5

pH = 14 - 5
pH = 9