Question

Ozone-layer is getting depleted because of

Options

• excessive use of automobiles

• excessive formation of industrial units

• excessive use of man-made compounds containing both fluorine and chlorine

• excessive deforestation.

Answer 1

excessive use of man-made compounds containing both fluorine and chlorine

Explanation:

Ozone-layer is getting depleted due to excessive use and emission of certain chemicals named ODS (ozone-depleting substances). ODS are the substances that react with ozone present in the stratosphere and destroy the same.
The major ODS CFCs (Chlorofluorocarbons) are synthetic harmful chemicals widely used in refrigerators and air conditioners as coolants, fire extinguishers, and propellants. Once released in the air, these harmful chemicals produce ‘active chlorine (Cl and CIO) radicals and fluorine in the presence of UV radiations. These radicals, through a chain reaction, then destroy the ozone by converting it into oxygen. Due to this, the ozone layer in the stratosphere becomes thinner. A single chlorine atom can destroy ‘ one lakh ozone molecules.