Study the following statements about ozone:(a) It is essential for breathing of living organisms.(b) It is used to disinfect water.(c) It absorbs ultraviolet rays.(d) Its proportion in air is about 3%. Which of these statements are correct?(a), (b) and (c) (b) and (c) (a) and (d) All four
Correct answer: (ii) (b) and (c)
Explanation: Ozone is used to disinfect water. It also absorbs the harmful UV rays entering the Earth's atmosphere.
[Extra information: Ozone is a naturally occurring gas in the atmosphere and is one of nature’s most powerful oxidizers. In the upper layers of the atmosphere, ozone filters the harmful ultraviolet light from the Sun and protects the earth from these harmful radiations. Due to its oxidizing property, ozone is also used in water treatment. Ozone water treatment is versatile and can be employed both commercially and at home. Ozone is an oxidant, it reacts with other substances and accepts their electrons.
Ozone water treatment begins with the creation of ozone in an ozone generator. Then, water is treated with ozone. It immediately starts oxidizing and eliminating contaminants, such as bacteria, viruses, and metals, and thus purifying the water systems.]
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