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Explain in brief how ozone layer is getting depleted. |
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Answer» • This layer is established due to an equilibrium between photo dissociation of ozone by UV – radiations and regeneration of ozone. O2 O + O O + O2 O3 (Ozone) But some chemicals / Pollutant react with it and degrade the layer. • Main chemicals to be responsible for destruction of ozone layer are : chlorofluorocarbons (CFCs), halogens (used in fire extinguishers), methane and nitrous oxide. • Out of these, most damaging is the effect of CFCs which are a group of synthetic chemicals and are used as coolants in refrigerators and air conditioners; as cleaning solvents, propellants and sterilant etc. • These CFCs produce “active chlorine” (Cl and ClO radicals) in the presence of UV–radiations. These active chlorine radicals catalytically destroy ozone and convert it into oxygen. As show |
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