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Composition and Properties of Air

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Composition of the atmosphere - definition

The atmosphere is a mixture of many gases and tiny solid particles. A clean city sample of air is made up of 78% of nitrogen and 21% of oxygen. Oxygen gas helps in burning and breathing. Without breathing oxygen, most living things cannot survive. Nitrogen is a colourless inert gas and has no taste or smell.

Functions of the atmosphere - definition

1. Air has weight and exerts pressure. Being pressured down it always remains in contact with land and water. 
2. Due to their physical contact, exchange of gases between air, land and water takes place on a continuous basis.
3. Soil absorbs oxygen and nitrogen due to this contact. Water vapours in air rise from oceans on account of evaporation.
4. Carbon dioxide in air helps in absorption of heat and keeps the earth warm at night.
5. The energy of the sun is responsible for keeping the atmosphere in a dynamic state.

Functions of atmosphere - definition

The atmosphere works as a place to contain the oxygen that is necessary for life, works as a blanket to shield the earth from radiation and helps to create the different types of weather that are felt on the Earth.

Atmosphere of the earth - shortcut

Its atmosphere is made up of life supporting gases such as oxygen, nitrogen and carbon dioxide. Other gases include Helium and Argon. Ozone present in the earth's atmosphere absorbs the harmful ultraviolet rays. The atmosphere also prevents loss of heat from the earth's surface and helps to keep the earth warm.

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