(1) When air is in ____________ it is called wind.

(2) The component of air that supports burning is called ____________.

(3) Our earth is surrounded by ____________.

(4) The aquatic animals use dissolved oxygen in water for respiration. This is possible because oxygen is ____________ in water.

(5) Nitrogen in the air is used on a large scale to manufacture ____________.

(1) We cannot see air.

(2) A firki rotates only in an open area or in a closed room with the ceiling fan switched on.

(3) Air is an opaque material.

(4) All living organisms require air for their survival.

(5) Air contains water vapours.

(2) What is atmosphere ?

(1) What is the composition of air ?

(3) Write the two uses of oxygen.

(1) Name the gases present in the air. Which one of them is most abundant?

(2) How will you say that air is dissolved in water?

(3) Name two processes supported by oxygen present in the air.

(4) Write the characteristics of ideal fuels.

(5) What will happen if the amount of oxygen is increased in the air?

(4) Explain oxygen with the help of a flow diagram.

(1) Prove that oxygen has 1/5th part in the air

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

(3) The mountaineers carry oxygen cylinders with them while climbing high mountains. Why?

(5) . What are the different ways by which air pollution can be controlled?

nitrogen

air in motion

Oxygen

Oxygen

everywhere