Equilibrium Question 287
Question: A weak acid HX has the dissociation constant $ 1\times {10^{-5}}M $ . It forms a salt NaX on reaction with alkali. The degree of hydrolysis of 0.1 M solution of NaX is [IIT JEE Screening 2004]
Options:
A) 0.0001%
B) 0.01%
C) 0.1%
D) 0.15%
Show Answer
Answer:
Correct Answer: B
Solution:
$ {X^{-}}+H_2O $ ⇌ $ HX+O{H^{-}} $
$ K_{h}=\frac{{10^{-14}}}{{10^{-5}}} $ so $ h=\sqrt{\frac{{10^{-9}}}{{10^{-1}}}}={10^{-4}} $
$ 100\times {10^{-4}}={10^{-2}} $ So, 0.01%.