What molecule is found in CFCs and HCFCs that depletes the ozone layer?

• A. Fluorine
• B. Carbon
• C. Chlorine
• D. Bromine

Answer: (C)

Chlorine is the molecule found in CFCs (chlorofluorocarbons) and HCFCs (hydrochlorofluorocarbons) that is primarily responsible for ozone layer depletion. When CFCs and HCFCs are released into the atmosphere, they eventually reach the stratosphere, where ultraviolet (UV) radiation breaks them down, releasing chlorine atoms.

These chlorine atoms are highly reactive and can catalyze the breakdown of ozone (O3) molecules. A single chlorine atom can destroy thousands of ozone molecules before it is deactivated, making it a potent ozone-depleting substance. This process contributes significantly to the thinning of the ozone layer, which protects the Earth from harmful UV radiation.

The other options do not contribute to ozone depletion in the same manner. While fluorine is present in CFCs and HCFCs, it does not have the same ozone-depleting effect as chlorine. Carbon is a structural component of these compounds but does not directly affect ozone. Bromine, although it can deplete ozone, is not the primary molecule involved in CFCs and HCFCs, which is why chlorine is the correct answer in this context.