Air Around Us

NCERT Solutions for Chapter 15 Air Around Us Class 6 Science

Book Solutions

1

What is the composition of air?

Answer

Air contains some gases mainly nitrogen, oxygen, small amount of carbon dioxide, water vapour and dust particles.
Exercises Page Number 153

2

Which gas in the atmosphere is essential for respiration?

Answer

Oxygen gas in the atmosphere is essential for respiration.
Exercises Page Number 153

3

How will you prove that air supports burning?

Answer

Step I: Two shallow containers are taken and burning candles are fitted into it.
Step II: Now, water is filled in the container at two different levels.
Step III: Both the candles are then covered with glass.
Step IV: After sometimes, we observed that the candles having less water in its container lights off.
This happened because the container having more water contains more oxygen and therefore it burnt for more time. Thus, it is proved that air supports burning.

Exercises Page Number 153

4

How will you show that air is dissolved in water?

Answer


Step I: Water in a pan is taken.
Step II: It is now boiled on stove.
Step III: We will observe tiny bubbles of water visible coming out from the bottom of the pan.
These tiny bubbles are coming due to the air dissolved in water. Thus, this proves that air is dissolved in water.

Exercises Page Number 153

5

Why does a lump of cotton wool shrink in water?

Answer

The lump of cotton contains air in it. When it comes in contact with water, the air pushed out from the vacant space and dissolved in water and thus a lump of cotton wool shrink in water.
Exercises Page Number 153

6

The layer of air around the earth is known as _______.

Answer

The layer of air around the earth is known as atmosphere.
Exercises Page Number 154

7

The component of air used by green plants to make their food, is _______.

Answer

The component of air used by green plants to make their food, is carbon dioxide.
Exercises Page Number 154

8

List five activities that are possible due to the presence of air.

Answer

Five activities that are possible due to the presence of air:
(i) Helps in seed dispersal and pollination.
(ii) Sailing of ships.
(iii) Flying of the birds and kites.
(iv) Gives us oxygen to respire.
(v) Helps in the rotation of windmill.
Exercises Page Number 154

9

How do plants and animals help each other in the exchange of gases in the atmosphere? 

Answer

Plants take in carbon dioxide in during photosynthesis give out oxygen in the atmosphere while animals take in oxygen and breathe out carbon dioxide during respiration. In this way, plants and animals help each other in the exchange of gases in the atmosphere.
Exercises Page Number 154