Question

What is Ozone layer? What are the reasons for its depletion? How the life on the Earth is affected by Ozone layer depletion?

Answer 1

Ozone layer is found in Stratosphere. The area about 15-20km above the sea is called Stratopshere. This layer protects us from the ultraviolet radiations ($\lambda =255nm$) coming from the Sun. This layer absorbs ultraviolet radiation. It acts as a blanket in the atmosphere
$O_{2\left(g\right)}+O_{\left(g\right)}\to O_{3\left(g\right)}$
Reasons for depletion of Ozone layter:
The main reason for the depletion of Ozone layer is the release of chlorofluorcarbons compounds (CFCs) in the atmosphere. These compounds are also called freons.
In the presence of UV radiations, CFCs are dissociated into nascent chloride and $ClO$ free radical. There intermediates are chemically active and convert Ozone to oxygen. In this way, due to continuous formation of chlorine-free radicals regularly dissociate ozone to oxygen
Effects of Ozone layer depletion:
The life of the Earth is affected by Ozone layer depletion as follows:
It causes burning sensation
It causes skin cancer
It causes destruction of life
It causes swelling of skin
It causes ageing of skin
It causes DNA mutation etc