Question

The active disinfectant property of bleaching powder is due to:

• A. Chlorine
• B. Hypochloric acid
• C. Hypochlorous acid
• D. Chloramines

Answer 1

The Correct Option is C

Bleaching powder is widely used as a disinfectant due to its ability to release active chlorine compounds. The key to understanding its disinfectant property lies in its chemistry and the reactions it undergoes when dissolved in water.

Bleaching powder, chemically known as calcium hypochlorite, releases chlorine when dissolved in water:
1. Ca(OCl)₂ + H₂O → Ca(OH)₂ + 2 HOCl

This reaction results in the formation of hypochlorous acid (HOCl). Hypochlorous acid is a highly effective disinfectant because:

• It is a weak acid and can easily penetrate microbial cell walls.
• It disrupts the vital processes within the microorganisms.
• Has a strong oxidizing action that inactivates essential enzymes and structures within the microbe.

Thus, the active disinfectant property of bleaching powder is primarily due to the formation of hypochlorous acid when it is mixed with water. This compound is responsible for effectively killing bacteria and other pathogens.

In conclusion, among the given options, the active disinfectant property of bleaching powder is due to: Hypochlorous acid.