Q. HA is a weak acid. The pH of 0.1 M HA solution is 2. What is the degree of dissociation ($\alpha$) of HA?
A) 0.5
B) 0.2
C) 0.1
D) 0.301
Explanation
(c)
$\therefore\ \ \ \ \ pH = 2$
$\therefore$ $\left\lbrack H^{+} \right\rbrack = 10^{- 2}$
$\left\lbrack H^{+} \right\rbrack = N.\alpha$
$10^{- 2} = 0.1 \times \alpha$
$\alpha = \frac{10^{- 2}}{0.1}$
$\alpha = 0.1$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.