Air Around Us Class 6 Notes CBSE Science Chapter 15 [Free PDF Download]

Air is an invisible gaseous material that surrounds the earth and is primarily composed of oxygen and nitrogen.

1. Atmosphere refers to the blanket of air that surrounds the world.

2. Air can be found in all places. Although we cannot see air, we can feel it.

3. The wind is the movement of air.

4. Air takes up space and is found in water and dirt.

5. Nitrogen, oxygen, carbon dioxide, water vapour, and a few more gases make up air. It may also contain some dust particles.

6. Life on Earth depends on the atmosphere.

7. Aquatic species breathe dissolved air in water, and plants and animals rely on each other for oxygen and carbon dioxide exchange from the air.

Different Layers of Atmosphere:

1. Troposphere 

2. Stratosphere 

3. Mesosphere 

4. Thermosphere 

Constituent of Air:

The main components of air are nitrogen and oxygen. Nitrogen makes up about 78 per cent of the air we breathe. Nearly 21% of the air is made up of oxygen. Carbon dioxide, water vapour, dust particles, and other gases make up the remaining 1%. The composition of gases in the air varies by location.

1. Nitrogen: Plants require nitrogen in order to grow.

2. Oxygen: All living things use oxygen to breathe and to help them burn food.

3. Carbon Dioxide: During respiration, plants and animals absorb oxygen and create carbon dioxide. Photosynthesis is carried out by green plants. It is emitted when you burn something.

4. Water Vapour: Water vapour is formed when water evaporates. Humidity refers to the amount of water vapour in the air. Variates from place to place, as well as during the day and night in the same location.

5. Dust and Smoke: Smoke comprises a small number of gases as well as fine dust particles. It is really dangerous. The number of dust particles in the air changes throughout time and from location to place.

Importance of Air:

1. Burning is aided by the presence of air.

2. Breathing necessitates the presence of air.

3. Plants require air to produce food.

4. Birds fly across the air. Air pressure also causes planes to rise in the air.

5. The wind is the term for moving air. The windmill rotates because of the wind.

6. Air helps in the rapid evaporation of sweat, which keeps us cool.