Primary 5 Cycles: Water

1. Water Water

2. Our Blue PlanetOur Blue Planet

3. Introduction Introduction
•Covers three-quarters of the earth
surface
•All living things need water to survive.
•Water exists in three different states:
-Solid
-Liquid
-Gaseous

4. Water in Solid State Water in Solid State
ice snow hail

5. Water in the Liquid StateWater in the Liquid State
•Most of the Earth’s water is sea water.
raindrops dew clouds

6. Water in Gaseous StateWater in Gaseous State
Water vapour Steam
Similarities:
•Both are colourless
•Both are water in gaseous state
Differences
At any temperature 100
0
C

7. Changing States of Water: Changing States of Water:
Heat GainedHeat Gained
•Solid to liquid: Melting (0
0
C)
•Liquid to Gaseous: Evaporation
: Boiling (100
0
C)

8. Changing States of Water: Changing States of Water:
Heat LossHeat Loss
•Liquid to Solid: Freezing (0
0
C)
•Gaseous to Liquid: Condensation

9. Changing States of Water: Changing States of Water:
Heat LossHeat Loss
•Liquid to Solid: Freezing (0
0
C)
•Liquid to Gaseous: Condensation

10. MeltingMelting
•From solid to liquid
•Gains heat
•Happens at 0
0
C
•Ice to water
•Temperature stays the same
•Heat gained to change state of water from
solid to liquid
•State of water during melting: solid and liquid

11. Freezing Freezing
•From liquid to solid
•Heat loss from water to the surrounding
•Happens at 0
0
C
•Water to Ice
•Temperature stays the same

12. Boiling Boiling
•From liquid to gaseous
•Gains Heat
•Happens at 100
0
C
•Water to Steam
•Temperature stays the same
•Heat gained to change state of water from
liquid to gaseous
•State of water: liquid and gaseous

13. Evaporation Evaporation
•From liquid to gaseous
•Gains heat
•Evaporation happens all the time and at any
temperature.
•Water to Water Vapour

14. Condensation Condensation
•From gaseous to liquid
•Loses heat
•Condensation happens due to temperature
difference
•Water Vapour to Water
•Steam to Water

15. Condensation Condensation
(100
0
C)
(10
0
C)
(100
0
C)
(70
0
C)
Faster
Slower
More water
droplets
Less water
droplets

16. Evaporation Evaporation
•The rate of evaporation depends on a
few factors:
-Presence of wind
-Humidity
-Temperature
-Area of exposed surface

17. Presence of Wind Presence of Wind
•Water evaporates faster in the presence of
wind.
•When water evaporates, water vapour
gathers above the surface of the water.
•Wind will carry the water vapour away,
making space for more water to rise.

18. Humidity Humidity
(Amount of water vapour in the (Amount of water vapour in the
air)air)
•High humidity: Large amount of water vapour in
the air
•Higher humidity Slower rate of evaporation
•There is little or no space in the air for any
more water vapour when humidity is high.

19. Temperature Temperature
•Higher temperature Faster rate of
evaporation

20. Area of Exposed SurfaceArea of Exposed Surface
•The larger the area of the exposed surface,
the greater the amount of evaporation.
Larger exposed
surface area
Smaller exposed
surface area

21. Area of Exposed SurfaceArea of Exposed Surface
0 fold 1fold 2 folds
Increase rate of evaporation

22. Video on processes of
water

24. Water Cycle Video 1

25. Water CycleWater Cycle
•Respiration
–Animals give out water vapour
Stage 1:
•Evaporation
–Heat from sun evaporate water from rivers,
lakes and sea
•Transpiration
–Plants give out water vapour through
stomata of leaves

26. Water CycleWater Cycle
Stage 2:
•Condensation
–Water vapour rises into the air and
condenses into water droplets

27. Water CycleWater Cycle
Stage 3:
•Precipitation
–Clouds become to heavy and fall as rain to
the ground

28. Water CycleWater Cycle

29. Main source of energy for
water cycle

30. Water Cycle Song:
Processes
Water Cycle Song