A solution of impure `KMnO_4` is prepared by dissolving 2g of it in IL of the solution. 20 ml of this solution required 24.2 ml of `N/(20)` sodium oxalate solution. The percentage purity of `KMnO_4` sample is :

Options

A. `95.6%`
B. `92.2%`
C. `98.0%`
D. `84%`

Answer

A

Explanation

`N_1V_1-=N_2V_2`
`N_1 xx 20 = (N)/(20) xx 24.2`
`N_1= (24.2)/(400) =(6.05)/(100)`
Strength `=(6.05)/(100) xx 31.6 = 1.91` g
% Purity `=(1.91)/(2.0) xx 100 = 95.5%`