Q7 of 805 Page 1

Why are there regular reminders to reduce the use of CFCs in theproduction of industrial and household appliances? Explain.

Chlorofluorocarbons (CFCs) are man-made industrial chemicals used in air conditioning systems, refrigerators, etc. These are non-flammable, non-reactive in the normal form but when CFC’s are released into the stratosphere, they are broken up by the UV light present, resulting in the release of chlorine. This chlorine acts as a catalyst with the ozone molecules creating chlorine monoxide and molecular oxygen. Chlorine atoms are not consumed in the reaction. The reaction of chlorine monoxide radical with atomic oxygen produces more chlorine radicals. So when CFCs are added to the stratosphere, they have a permanent damaging effect on the ozone layer.


The equations are as given where Cl is chlorine, ClO is chlorine monoxide, O2 is oxygen, O3 is ozone and CF2Cl2 is dichlorodifluoromethane.


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