Question

With the help of an activity show that air contains water vapours

Answer 1

when we pour cold water in glass. we see water droplets on the outer surface of glass. this shows that air contains water vapour which on coming in contact with cold surface of glass loses energy and get converted into droplets.

Answer 2

Take a steel in a glass and pour cold water in that glass...you will observe that after a fraction of second droplets of water will be seen on the outer surface of steel glass...

these conclude that water vapors are present in the air and when it comes in contact with the surface of steel glass...I get condensed..