Question

22) How will you say that water vapour is present in
air?​

Answer 1

Answer. place a cold bottle outside , you will see few drop of water at the surface of the bottle. this phenomena shows that the water vapour is present in the air because when a gaseous substance get low temperature , it turns into the liquid state.

Answer 2

Answer:

a)Take out a bottle of soft drink from the refrigerator and place it on the table. b)Observe it for few minutes.

c)you will see small drops of water appearing on the outer surface of the bottle.

d) This is because water vapour present in the air condenses and forms small drops of water.

e) This activity proves that air contains water vapour.