Question
fforts are being made for substituting the chemicals like CFCs. Why?
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Answer
CFC is a potent greenhouse gas and leads to global warming. It contributes to ozone depletion in the upper atmosphere and therefore are being replaced by products like hydrofluorocarbons (HFCs). But it is to be mentioned that these HFCs are not 100% efficient as some of them might also act as greenhouse gas (example- HFC-134a or R-134a). Therefore, excess use of the substitutes is also not recommended. Thus, necessary steps are still to be taken towards this direction and modifications are still required.
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