What is the role of ultraviolet (UV) radiation in the water purification systems?1. It inactivates/kills the harmful microorganisms in water.2. It removes all the undesirable odours from the water.3. It quickens the sedimentation of solid particles, removes turbidity and improves the clarity of water.Which of the statements given above is/are correct?
✓ Correct answer: a) 1 only
ExplanationStatement 1 is correct: Ultraviolet (UV) radiation effectively neutralizes harmful microorganisms like bacteria, viruses, and protozoa.It damages their DNA by disrupting the thymine bases, preventing reproduction and rendering them harmless.Statement 2 is incorrect: UV radiation does not remove chemical compounds or gases that cause undesirable odors in water.These require additional processes like activated carbon filtration or oxidation techniques.Statement 3 is incorrect: UV radiation does not affect solid particles, turbidity, or water clarity.These issues require mechanical filtration or sedimentation processes, such as sand filters or coagulation methods.46
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