Air and water · वायु और जल
A free Chemistry lesson for Class 5 children.
Air is a mixture of gases. It is mostly nitrogen and oxygen.
We cannot see air, but it takes up space and has weight.
The heat of the Sun turns water into water vapour. This is evaporation.
High in the sky the vapour cools into tiny drops and forms clouds. This is condensation.
Water falls from the clouds as rain, snow or hail. This is precipitation.
Rainwater collects in rivers, lakes, seas and under the ground.
This journey of water, round and round, is called the water cycle.