Air Around Us, Composition of Air, Primary Usage of Oxygen, Uses of Air

Glide to success with Doorsteptutor material for CBSE : fully solved questions with step-by-step explanation- practice your way to success.

Download PDF of This Page (Size: 116K)

What is Air?

1. Air is the Earth’s atmosphere.

2. It has an indefinite shape and volume.

3. It is colourless and odourless.

4. Air is needed by all living thing; we cannot see air but we can feel it.

5. It is the clear gas in which living things live and breathe

6. Air in motion is called wind.

7. Air occupies space, air has weight and it is present in water and soil.

Composition of Air

It is a mixture of gases, water vapors and dust particles. The composition of air is

Composition of Air
Composition of Air








He, etc.





Primary Usage of Oxygen

Primary Usage of Oxygen
Primary Usage of Oxygen


It helps in burning of fuel


All living being uses air for breathing and respiration

Primary Usage of Nitrogen

Primary Usage of Nitrogen
Primary Usage of Nitrogen


Nitrogen is used by plants and animals to synthesize proteins in the bod


Nitrogen is used to manufacture ammonia used for in many industries.

Primary Usage of CO2

Primary Usage of CO_2
Primary Usage of CO_2


It is used by plants in synthesizing their food by the process of photosynthesis

Fire extinguishers

It is used in fire extinguishers.

Uses of Air

1. Animals use air for respiration.

2. Plants use air to prepare their food. (Photosynthesis)

3. Power generation by wind mills. Wind mill helps in electricity generation.

4. Burning of fuels and substances.

5. Air plays important role in water cycle

6. Birds, insect can fly because of the presence of air

Interdependence of Oxygen and Carbon Dioxide

  • Plants consume oxygen for respiration but they also produce oxygen by photosynthesis by consuming Carbon dioxide. But plants produce more oxygen then they consume. So we generally say that plants produce oxygen by absorbing Carbon Dioxide Animals also respire I.e. they inhale oxygen and gives out carbon dioxide in the atmosphere. So oxygen and carbon dioxide balance is maintained in the atmosphere.

  • So we can say that Carbon Dioxide is replenished by the process of respiration and oxygen is replenished by the process of photosynthesis.

Developed by: