Question

What happens when ethanol is heated with alkaline KMnO$_4$? Write chemical equation involved.

Hint:

KMnO$_4$ oxidizes ethanol → Ethanoic acid.

Answer 1

What Happens When Ethanol is Heated with Alkaline KMnO₄?

When ethanol (C₂H₅OH) is heated with alkaline potassium permanganate (KMnO₄), it undergoes an oxidation reaction. Ethanol is oxidized to ethanoic acid (acetic acid).

Detailed Explanation:

1. Nature of Reaction:
Alkaline KMnO₄ is a strong oxidizing agent. It provides oxygen and converts the primary alcohol (ethanol) first into ethanal and then further oxidizes it to ethanoic acid.

2. Observation:
The purple color of potassium permanganate gradually disappears during the reaction because KMnO₄ gets reduced while ethanol gets oxidized.

3. Product Formed:
The final product of the reaction is ethanoic acid (CH₃COOH).

Chemical Equation:
3C₂H₅OH + 2KMnO₄ → 3CH₃COOH + 2MnO₂ + 2KOH + H₂O

(In alkaline medium)

Conclusion:
When ethanol is heated with alkaline KMnO₄, it gets oxidized to ethanoic acid. This is an oxidation reaction in which KMnO₄ acts as an oxidizing agent.