Eliminating water-borne pathogens is known as disinfection. Which of the following agents is used for water disinfection?
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Answer: A. Chlorine
Explanation
Chlorine is a powerful chemical oxidant that rapidly destroys harmful microorganisms in municipal water supplies. Adding chlorine compounds eliminates water-borne pathogens preventing the spread of infectious water diseases. Residual chlorine provides continuous disinfection protection throughout public water distribution piping networks. Water disinfection destroys pathogenic bacteria viruses and protozoa making water safe for human consumption. Chlorination chemistry involves forming hypochlorous acid which penetrates microbial cell walls effectively. Public health standards mandate minimum disinfectant residual levels in treated municipal drinking water.
Municipal water treatment plants worldwide utilize chlorine gas or hypochlorite salts for daily disinfection. Emergency disaster relief operations distribute chlorine tablets to purify contaminated drinking water sources. Swimming pool operators maintain strict chlorine residual concentrations to prevent swimmer illness outbreaks. Alkalis adjust pH levels during water treatment but lack sufficient broad-spectrum pathogen disinfection power. Benzene hexachloride is a persistent organic pesticide rather than a safe municipal water disinfectant. Alkyl benzene sulphonate functions as a synthetic surfactant detergent rather than a water pathogen killer.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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