Give reason : a gas exerts pressure on the walls of the container.

Explanation

Liquids and gases exert pressure on the walls of their container. This can be illustrated with the help of following examples :
(i) It is not possible to inflate a balloon which has holes on its sides. This is because air exerts pressure on the sides of the balloon.
(ii) Air escapes out of the bicycle tube which has a puncture because air exerts pressure on the inner walls of the tube.