NITROGEN
Nitrogen is a colourless, tasteless and odourless gas. Nitrogen gas is slightly soluble in water. Nitrogen gas is not essential for breathing (or respiration). Nitrogen gas neither burns itself nor supports the process of burning. That is, nitrogen does not support combustion. Nitrogen is a very unreactive gas. In this respect, nitrogen is just the opposite of oxygen (which is a very reactive gas.
Nitrogen gas present in air is important for living things. All the living things need nitrogen com pounds for their growth. The plants use nitrogen gas of the air to make proteins. These proteins are used by the plants for their own growth as well as for the growth of human beings and other animals. Thus, nitrogen is needed by plants to make protein.
Oxygen:-
Oxygen is a colourless, tasteless and odourless gas. Oxygen gas is slightly soluble in water. Oxygen gas is essential for breathing (or respiration). We can live for several days without food and water but we will die very quickly without oxygen. So, the oxygen present in air is important for the living things. All the living things need oxygen of air for breathing.
Oxygen gas does not burn itself but it allows other things to burn in it. So, oxygen is a supporter burning (or supporter of combustion). Thus, oxygen (or air) is also necessary for the process of burning (or combustion) of fuels such as wood, coal, kerosene, petrol and LPG. Thus, oxygen supports life and combustion. Let us discuss this in somewhat detail.