Question

The charge required for the oxidation of one mole of $M{n}_3{O}_4\to Mn{O}_4^{2-}$ in alkaline medium is: (assume 100% current efficiency)

• A. 10/3F
• B. 6F
• C. 10F
• D. 4F

Answer 1

Answer: (C)

10F

$M{n}_3^{\frac{+8}{3}}{O}_4+O{H}^{-}\to 3M{n}^{+6}{O}_4^{2-}$

Change in charge $=(6-\frac{8}{3})\times 3$

$=18-8$

$=10$

$\therefore$ 10 F charge is required to reduce 1 mole of $M{n}_3{O}_4$.