MCQ
The worst enemy of ozone is :
- ALiquid $\mathrm{NH}_3$
- B$\mathrm{SO}_2$
- C$ \mathrm{CH} 4$
- ✓$\text{CFCs}$
✓
Answer
Correct option: D.
$\text{CFCs}$
The ozone hole is thinning of an ozone layer which is present in the stratosphere region around $26 - 30 \ \text{kms}$ above the Earth surface. The ozone hole is caused by chlorofluorocarbons $\text{(CFCs)}$ found in air conditioners, aerosol spray cans, refrigerants etc. $\text{CFCs}$ can not be removed in troposphere and moves in Stratosphere layer where it reacts with ozone, thereby releasing of free chlorine atoms and causes the ozone layer to deplete. It serves as a shield from the harmful ultraviolet $B$ radiation emitted by the sun. Ozone hole becomes a cause of concern as it allows $\text{UV}$ radiations to reach the earth surface which causes major problems like Skin cancer, reduction in the rate of photosynthesis.
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