Why is Oxygen important?
- Humans and other organisms use oxygen for
- Oxygen is also utilised for metabolism and digestion of
- During decomposition, a few microorganisms utilise atmospheric
- Oxygen is an essential element required for combustion. Combustion is a process where heat is released by burning organic matters, wood, fossil fuels in the presence of
What is the Oxygen cycle?
The oxygen cycle is the circulation of oxygen in various forms through nature.
Animals use oxygen to respire and give out carbon dioxide. This carbon dioxide is taken up by algae and terrestrial green plants to carry out the process of photosynthesis. During this process, oxygen is given out as a by-product. This gets the used oxygen back into the atmosphere thus completing the cycle.
What is the Ozone layer?
The ozone layer is a thin part of the earth’s atmosphere that absorbs almost all of the sun’s harmful ultraviolet light.
How is the ozone layer formed?
Ozone is a molecule with 3 oxygen atoms. It is a gas that occurs naturally in the earth’s upper
atmosphere.
Presence of [latex] O_{2}[/latex] and [latex] O_{3}[/latex] in the atmosphere
 Oxygen molecules are made up of two atoms. These molecules are found in the lower levels of
the atmosphere which are closer to the earth’s surface. This is the oxygen we breathe.
When oxygen molecules in the atmosphere are struck by the ultraviolet radiations of the sun, they split. The two oxygen atoms which were bound to each other are set free. These single oxygen atoms, in order to be stable, need to combine with some molecule. So they go on to join the existing oxygen molecules to form a molecule with 3 oxygen atoms, that is ozone.
Since the ozone molecules are not stable, they do not exist nearer to the surface of the earth and form a layer high above in the atmosphere.
Why is the ozone layer important?
Though breathing in ozone can result in a number of health effects, mainly respiratory problems, the ozone layer actually protects us from the harmful radiations of the sun. It filters the harmful rays of the sun and helps us stay healthy.
Ozone layer protects from UV rays
 Depletion of ozone layer
In the 1980s, when meteorological departments studied the ozone layer cover, they discovered the presence of an ozone hole. Though it is not literally a hole in the ozone layer, it is an area where the ozone molecules are less dense than the rest of the layer.
And a less dense ozone layer will not be able to protect the earth from the ultraviolet rays of the sun as effectively.
What causes the depletion of the ozone layer?
The chlorofluorocarbons (CFCs) that are emitted by the various processes on the earth by humans cause ozone depletion. They react with the ozone molecules and thus destroy the ozone molecule.