Question

The degree of dissociation of acetic acid is given by the expression $\alpha =0.1\times C^{-1}$ (where C = concentration of the acid). What is the pH of the solution?

• A. 1
• B. 2
• C. 3
• D. 4

Answer 1

Answer: (A)

1

$\left[H^{+}\right]=C\times \alpha$

$\left[H^{+}\right]=C\times \frac{0.1}{C}$

$\left[H^{+}\right]=0.1M$

$pH=-log[H^{+}$]

$pH=-log\left[0.1\right]=-log[{10}^{-1}$]

$\Rightarrow pH=1$

Hence, option A is correct.