Water is a necessary resource for life that exists in three states: liquid, solid, and gas. It can be found in oceans, rivers, lakes, underground, as snow in mountains, and as ice at the poles. The water cycle describes how water evaporates from bodies of water into vapor due to heat from the sun, condenses into clouds, and falls back to earth as precipitation where it collects in bodies of water to repeat the cycle. Proper water management through reservoirs is important, as not all water is safe for drinking and some areas face water scarcity.

1. UNIT 7
WATER
• Water is a liquid.
• Water has no smell, taste or colour.
• Its shape depends on
the container it is in.

2. • Water is neccesary for life.
• People, animals and plants need water to
survive.
• People need to drink at
least 1 litre a day.
• Many animals live in water.

3. Where can we find water?
• In the sea, rivers and lakes.
• Underground.
• In the top of the
mountains, in the form of
snow.
• In the North and South Poles, in the form of ice.

4. Drinking water
• It’s safe for human drinking.
• Not all water is safe.
This is ‘non-drinking water’.
• In some parts of the world
there is very little water.
• We have to spend
less water.

5. • To store water
from rainfall and
rivers we use
reservoirs.
Satellyte wiew of ‘Peñarroya’ reservoir, near Socuéllamos.

6. • In Socuéllamos, water
we use is
underground.
We get water from wells.

7. The three states of water
• Water we drink is liquid water.
• Ice, snow and hailstones
are solid water.
• Water vapour
is a gas.

8. Water can change states
Solid
Gets very cold
Liquid water
SOLIDIFICATION

9. Liquid water
gets warm
Ice or snow (solid)
MELTING

10. water
vapour
gets hot
liquid water
EVAPORATION

11. liquid water
ld
co
ts
ge
water vapour
CONDENSATION

12. The water cycle
• Liquid water in
the sea, rivers and
lakes evaporates
because of heat from
the Sun.
• Liquid water becomes
water vapour
1.EVAPORATION

13. • Water vapour rises in the air, gets cold
and changes into drops of water.
• Drops of water form clouds
2. CONDENSATION

14. • Water from clouds
falls as rain.
• If it is very cold,
in the form of snow.
3. PRECIPITATION

15. • Water from rain or snow forms rivers, and
lakes.
• Plants use rain
water.
• Some rain water goes
underground and into
the sea.
WATER CYCLE STARTS AGAIN