Question

What amount of electric charge is required for the reduction of 1 mole of MnO$_4^{2-}$ into Mn$^{2+}$?

• A. 1F
• B. 5F
• C. 4F
• D. 6F

Hint:

For redox reactions, remember that the number of electrons involved is key to calculating the charge required.

Answer 1

The Correct Option is C

Reduction of MnO$_4^{2-}$ to Mn$^{2+}$ requires considering the oxidation state of Mn. In both MnO$_4^{2-}$ and Mn$^{2+}$, manganese is in the +2 oxidation state, indicating no change in oxidation state. Nevertheless, the reduction process necessitates the addition of 2 electrons per ion. For 1 mole of MnO$_4^{2-}$, 4 moles of electrons are consumed, equivalent to a charge of 4 Faradays.