Question

When potassium permanganate is titrated against ferrous ammonium sulphate, the equivalent weight of potassium perman- ganate is

(a) Mol. wt/10

(b) Mol. wt./5

(c) Mol. wt./2

(d) Mol. wt.

Answer 1

Correct option is (b) Mol. wt./5

Ox. No. of Mn decreases from +7 in KMnO₄ to + 2 in Mn²⁺.

MnO₄^- + 8H⁺ + 5e^- → Mn²⁺ + 4H₂O