2 September 2014

( Science) All about Air

Air is essential for all living beings. It supports life on earth. It is utilized by all the living organisms like plants, animals and microorganisms.Air is present everywhere on earth.

Atmosphere : 

Atmosphere is a thin layer of air surrounding the earth. The atmosphere is dense at the surface of the earth and becomes thinner as one moves up.The movement of air is called breeze or wind depending on its velocity or speed. 

Must Read : Air Pressure

Properties of air:

  • Transparent
  • Colourless
  • Occupies space

Components of air:

  • Nitrogen
  • Oxygen
  • Carbon dioxide
  • Water vapour
  • Smoke and dust particles


  • Is the major component of air
  • Does not support burning


  • Is the second largest component present in air
  • Supports burning
  • Helps in respiration process.

Smoke and Dust:

  • Present in minute amounts
  • Harmful to living organisms.

Oxygen is used by all living organisms in the process of respiration. They give out carbon dioxide to the environment. 

Carbon dioxide present in air is used by plants in the process of photosynthesis. They give out oxygen as a by-product.

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