Take a bottle containing cold water out in the hot. after some time you will notice droplets of water around it. the cold surface of the bottle condenses the water vapour present around it into water droplets. this activity proves that air contains water vapour.
Megha answered this
write two application of evaporation?
Aditya Jain answered this
if you take a pot and keep it in sunlight
after sometime you will see that there is less water in the pot.
This activity proves that air contains water vapour