Water.unit2

WATER

• 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.

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.

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.

• To store water

from rainfall and

rivers we use

reservoirs.

Satellyte wiew of ‘Peñarroya’ reservoir, near Socuéllamos.

• In Socuéllamos, water we use is underground.

We get water from wells.

The three states of water

• Water we drink is liquid water.

• Ice, snow and hailstones

are solid water.

• Water vapour

is a gas.

Water can change states

Liquid water

Solid

G

ets

very

col

d

SOLIDIFICATION

Ice or snow (solid)

Liquid watergets warm

MELTING

liquid water

water

vapour

g

ets

hot

EVAPORATION

water vapour

liquid water

CONDENSATION

gets

col

d

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

• Water vapour rises in the air, gets cold and changes into drops of water.

• Drops of water form clouds

2. CONDENSATION

• Water from clouds

falls as rain.

• If it is very cold,

in the form of snow.

3. PRECIPITATION

• 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