Chlorination is a process used for water purification. The disinfecting action of chlorine is mainly due to
- AThe formation of hydrochloric acid when chlorine is added to water
- BThe formation of hypochlorous acid when chlorine is added to waterCorrect
- CThe formation of nascent oxygen when chlorine is added to water
- DThe formation of hydrogen when chlorine is added to water
Explanation
The correct answer is B because when chlorine is added to water, it undergoes a chemical reaction to form hypochlorous acid and hydrochloric acid. Among these, hypochlorous acid is the active disinfecting agent. It is a weak acid that can easily penetrate the cell walls of bacteria and other microorganisms. Once inside, it destroys their vital proteins and enzymes through oxidation, effectively killing the pathogens. While hydrochloric acid is also formed, it does not contribute significantly to the disinfection process. Therefore, the germicidal action of chlorination is primarily attributed to the formation of hypochlorous acid.
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