Question

A dilute ferrous sulphate solution was gradually added to the beaker containing acidified permanganate solution. The light purple color of the solution fades and finally disappears. 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

The correct option is (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.