Give two uses of the following components present in air:

(a) oxygen

(b) nitrogen

(c) carbon dioxide

(d) water vapour

(a) Oxygen

1. For respiration in plants and animals
2. Oxygen is an essential component of burning or combustion

(b) Nitrogen

1. Nitrogen is needed to prepare a vital nutrient protein.
2. Food packaging and storing food.

(c) Carbon dioxide

1. Dry ice(solid carbon dioxide) is used as a refrigerant.
2. Carbon dioxide is used to prepare fizzy drink like soda-water.

(d) Water vapour

1. Water vapour present in the air provides moisture for both plants and animals.
2. It also helps in predicting climatic conditions of a particular area.