Suatu larutan amonia mempunyai pH = 10 log 2. jika kb = 2 x 10^-5, maka konsentrasi larutan tersebut adalah ?

pH = 10 + log 2
pOH = 14 - (10 + log 2)
= 4 - log 2
[OH-] = 2 × 10^-4

[OH-] = akar (Kb × M)
2 × 10^-4 = akar (2 × 10^-5 × M)
4 × 10^-8 = 2 × 10^-5 M
M = 4 × 10^-8 / 2 × 10^-5
= 2 × 10^-3 M