0.1 M formic acid solution is titrated against 0.1 M NaOH solution. What would be the difference in pH between 1/5 and 4/5 stages of neutralization of acid?

Options

A. `2 "log" 3//4`
B. `2 "log" 1//5`
C. `"log" 1//3`
D. `2 "log" 4`

Answer

D

Explanation

Solution is acidic buffer at both stages. Difference in `P^(H)` (at` 4//5` and `1//5`) `= log 4 - "log" (1)/(4)`
`= 2 log 4`