UPSC Combined Geo-Scientist, Mains · 2019 · Mains Paper I

Q1(a). Permanganate and iron(II)

Question

Complete the following reaction and balance it by ion-electron method: MnO₄⁻ + Fe²⁺ + H⁺ →.

MnO₄⁻ + 5Fe²⁺ + 8H⁺ → Mn²⁺ + 5Fe³⁺ + 4H₂O.

Reduction: MnO₄⁻ + 8H⁺ + 5e⁻ → Mn²⁺ + 4H₂O.
Oxidation: Fe²⁺ → Fe³⁺ + e⁻. Multiply by five and add the half-reactions.
The five electrons cancel. Charge is -1+10+8=+17 on the left and 2+15=+17 on the right; all atoms also balance.

The full model answer

As written for the answer booklet: the diagram carries the working, the lines stay short. Read here only; it is not offered as a download.

CoversPermanganateiron(IIRedox balancing