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Water in lakes, ponds and rivers contain dirt and germs. It is not safe to
drink. This water must be filtered before drinking.
Think &
Answer Do we need water for all activities? Name any five activities for which we dont
need water.
How does water come to our house?
Water from lakes and rivers is sent to water treatment plants where it is
filtered to remove dirt. Then
it is treated with chemicals to
kill germs. The cleaned water
is sent through underground
pipes to huge storage tanks.
The stored water is then sent
to our houses through pipes.
We get this water through
taps connected to the pipes.
Did You Many people do not have water supply in their homes. They transport water
Know? from public taps or wells. Some people have to walk long distances to bring
home water.
States of Water
There are three states of water: ice, water and water vapour. When water
is heated or cooled, it changes form. For example, when we place ice cubes
in a bowl at room temperature, they slowly melt into water.
When water is heated, it produces steam. Steam is simply water vapour.
When a chilled plate is placed against rising steam, water droplets form on
the plate’s underside.
When water droplets are collected in an ice tray and placed in the freezer,
they change into ice.
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