The pH of a 0.1 M aqueous solution of a weak acid (HA) is 3. What is its degree of dissociation ?

Options

A. `10%`
B. `25%`
C. `50%`
D. None of these

Answer

D

Explanation

`HA hArr H^(+)+A^(-)`
`[H^(+)]=calpha=10^(-3)`
As` c=0.1 M implies 0.1 alpha=10^(-3)`
or `alpha=10^(=-2)` or `% alpha =1%`