Grade 06 Science Lesson 03

1. Grade 06 Science
Unit 03An age of Smarters Cloud Nine Knowledge Hub

2. Types of water based on salinity.
The dissolution of different things in water is a special property of water.
Sodium Chloride is a type of salt dissolved in sea water.
Salinity is the concentration of salt in different types of water.
Fresh water
The amount of salt
dissolved in fresh
water is very low.
Marine water
The amount of salt
dissolved in marine
water is very high.
Brackish water
The amount of salt dissolved
in brackish water is less than
marine water but more than
fresh water.

3. Activity
Give some examples of where you can find
fresh water, marine water and brackish water.

4. Importance of Water.
Water is one of the most important substances on earth. All plants and animals
must have water to survive. If there was no water there would be no life on
earth.

5. Importance of Water.

6. Importance of Water.
Helps plants absorb
minerals
Helps keep the plant
rigid
For photosynthesis

7. Water, a limited resource.
Water is a natural resource and we must protect and conserve this
gift of nature.
Sea water in seas and
oceans (97.41%)
Solid state of water
(2.58%)
Water than can be
consumed (0.01%)

8. Water pollution
The addition of waste materials to water till it becomes unsuitable
for use is known as water pollution.

9. Water pollution
Pollution of surface water affects ground
water. The poisonous chemicals in surface
water gets added to ground water that we
use to drink. Drinking this polluted water
can cause many serious illnesses such as
cancer, kidney failures and other terminal
diseases.

13. Many of the rivers in
Sri Lanka are
polluted.
Unfortunately humans
have caused pollution in
many fresh water
resources. We are
responsible for cleaning
them up so they no
longer inflict any harm
for humans or animals.

15. Let’s conserve our water!
Only 0.01% of the water in the world is suitable for
consumption.
So we have to protect and conserve the little we have.
Simple precautions can be taken to reduce wastage and
pollution of water.

17. Use organic products. Keep toxic products like
paint, cleaning products and polishes stored
away carefully. Do not dispose these products in
the sink or toilet

18. Dispose your trash in a proper manner.
Use the recycling habit as
much as possible.

19. Do not throw litter into
streams, lakes, rivers, or
seas.
If you see litter on
beaches or in water
systems, after making
sure that it is safe,
collect them and dispose
them off in any nearby
waste disposal system.

20. Use natural fertilizers and pesticides as much
as possible, or if not, do not overuse them or
over-water gardens and lawns.