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Pollution of Air and Water — Science STD 8 — Question

Gujarat BoardEnglish MediumSTD 8SciencePollution of Air and Water4 Marks
Question
What do $CFCs$ stand for? Name some devices where $CFCs$ are used. Why $CFCs$ are considered as pollutants?
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Answer

$CFCs$ stands for chlorofluorocarbons. These are the chemical compounds made of chlorine, fluorine and carbon elements. $CFCs$ are used in refrigerators, air conditioners and aerosol sprays. $CFCs$ are considered as pollutants because these are depleting the useful ozone layer of the upper atmosphere. This happens as follows:$CFCs$ released into the air, goes up and ultimately reach high into the atmosphere where the protective ozone layer exists. The chlorofluorocarbons reacts with ozone gas of ozone layer and destroy it gradually. This allows the harmful ultraviolet rays of the sun to reach on the earth and can cause skin cancer, cataract and destruction of plants, including crops.

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