Ozone Depletion

(i) Ozone is a molecule formed by three oxygen atoms.

(ii) It is a deadly poison.

(iii) At higher levels of the atmosphere, it forms an ozone layer which protects the earth’s surface from harmful ultraviolet (UV) radiations from the sun.

(iv) The UV radiation splits molecular oxygen (O₂) into free oxygen atoms which combine with molecular oxygen to form a molecule of ozone

O₂ + UV → [O] + [O]

2O₂ + 2[O] → 2O₃(Ozone)

(v) Some ozone depleting substances like chloro- fluorocarbons react with ozone present in the stratosphere and depletion the ozone layer which causes global warming.

Harmful Effects of Ozone Depletion

• Skin cancer
• Cataract
• Weakening of the immune system
• Decrease in reproductive capacity
• Inhibition of photosynthesis.