Question

A dilute ferrous sulphate solution was gradually added to the beaker containing acidified potassium permanganate solution.and finally disappeared. Which of the following is the correct explanation for the observation?
(A) KMnO4 is an oxidising agent, it oxidises FeSO4.
(B) FeSO4 acts as an oxidising agent and oxidises KMnO4.
(C) The colour disappears due to dilution; no reaction is involved.
(D) KMnO4 is an unstable compound and decomposes in presence of FeSO4 to a colourless compound.

Answer 1

(A) KMnO₄ is an oxidising agent, it oxidises FeSO₄.

Potassium permanganate (KMnO₄) in presence of dil. H₂SO₄, i.e., in acidic medium acts as strong oxidising agent. In acidic medium, KMnO4 oxidises ferrous sulphate to ferric sulphate.