Question
  1. Expand CFC.
  2. How does it reduce ozone to oxygen?

Answer

  1. Chlorofluorocarbons.
  2. In stratosphere, UV rays act on CFCs thereby releasing Cl, which degrades ozone, releasing molecular oxygen. Cl atoms act merely as catalyst and are not consumed in the reaction. A single chlorine atom can convert 1 lakh molecules of ozone into oxygen.

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