Air

Air can exert pressure in ................. and ................. direction.

During the process of photosynthesis, plants produce one of the constituents of air .................

Nitrogen is ..................... and oxygen is ..................... in air.

Plant produces food and ................... during photosynthesis.

The major constituents of air are .................

..................... is required for burning.

Air is not a pure substance; it is a ................. .

Air is .................... and .................... .

Moving air is known as ................... .

The earth is surrounded by a layer of air called the .................

Air occupies ................. and has ................. .

The layer of air around the earth upto few km is known as .................... .

Dust and smoke cause ................. of air when present in excess.