Q. In acid medium, solution of potassium permanganate (mol. Wt. $158$) reacts with reducing agents according to the equation. $MnO _{-}^{-}+8 H ^{+}+5 e ^{-} \rightarrow Mn ^{2+}+4 H _{2} O$. The mass of $KMnO _{4}$ required to prepare $500\, ml$ of $0.2\, N$ solution is

Solution:

Correct answer is (a) $3.16$ grams