Question

On passing $H_{2}S$ gas through acidified $KMn{O}_4$ solution, we get:

• A. $K_{2}S{O}_3$
• B. $S$
• C. $M{n}^{2+}$
• D. $Mn{O}_2$

Answer 1

Answer: (B), (C)

The correct options are
B $S$
C $M{n}^{2+}$

On passing $H_{2}S$ gas through acidified $KMn{O}_4$ solution, we get $S$ and $M{n}^{2+}$.

The redox reactions are as follows:
$Mn{O}_4^{-}+8H^{+}+5e^{-}\to M{n}^{2+}+4H_{2}O]\times 2$
$H_{2}S\to 2H^{+}+S+2e^{-}]\times 5$

The overall reaction is as follows:
$2Mn{O}_4^{-}+5H_{2}S+6H^{+}\to 2M{n}^{2+}+5S+8H_{2}O$

Sulphur is obtained due to the oxidation of $H_{2}S$ by $KMn{O}_4$.