The bleaching action of bleaching powder is due to: MCQ with Answer and Explanation

The bleaching action of bleaching powder is due to:
A. Hydrogen peroxide
B. Ozone
C. Sodium hypochlorite
D. Chlorine liberated in the presence of acid
Answer: Option D
Solution (By JKExamLibrary)
Bleaching powder (CaOCl₂) reacts with dilute acids or even CO₂ from air to release chlorine: CaOCl₂ + H₂SO₄ → CaSO₄ + Cl₂ + H₂O; or with CO₂: CaOCl₂ + CO₂ → CaCO₃ + Cl₂. The chlorine gas acts as oxidizing and bleaching agent. Actually the bleaching is due to nascent oxygen produced by chlorine with water: Cl₂ + H₂O → 2HCl + [O]. But the key is chlorine liberation.

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