Chlorofluorocarbons (CFCs) are important compounds that are used as refrigerants but these are also responsible for ozone layer depletion. If a chlorofluorocarbon CFCl3 is present in stratosphere, which of its reaction intermediates are actually responsible for the breakdown of the ozone molecule?
Correct answer: B. Cl* and ClO*
- A. CFCl2* and Cl*
- B. Cl* and ClO*
- C. CFCl2* and ClO*
- D. CFCl2 and CFCl3
Explanation
In the stratosphere, when a chlorofluorocarbon (CFC) like CFCl3 (also known as CFC-11) is exposed to ultraviolet (UV) radiation, it breaks down into chlorine radicals (Cl*) and a CFCl2 radical. These chlorine radicals (Cl*) are highly reactive and can catalyze the breakdown of ozone (O3) molecules into oxygen (O2). This catalytic cycle involving Cl* and ClO* (chlorine monoxide radical) is responsible for the depletion of the ozone layer.
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