5
UNIT
Water
53
L O O K & R E A D
The hydrosphere is the water on Earth’s surface, the water under the ground
and also in the air. Living things need it to live. Water is present as salt water
in seas and oceans, and fresh water in the ice caps, rivers and lakes. The water
that we drink is fresh water. There are three states of water: liquid, solid and
gas. There is always the same amount of water on Earth and in our atmosphere,
but it changes state all the time. By the end of this unit you will know about the
hydrosphere and what the different forms of water on Earth are like.
