Degree of dissocation of `CH_(3)COOH` and `NH_(4)OH` are the same. If `0.1 M` solution of `CH_(3)COOH` has `pH = 4.0`, them `pH ` of `0.01 M NH_(4)OH` will be

Options

A. 4
B. 7
C. 10
D. 14

Answer

C

Explanation

`pH = 4, [H^(+)] - 10^(-4)`
`[H^(+)] = sqrt(kac)`
`10^(-4) = sqrt(ka xx 10^(-2))`
`ka = 10^(-6)`
`[OH^(-)] = sqrt(kb xx c) = sqrt(10^(-6) xx 10^(-2)) = 10^(-4)`
`pOH = 4`
`pH = 14-4 = 10`