Les. 4 & 5 - Water  Safe for Drinking & Every Household

     Q1. Answer the following :

      1. What is known as potable water?

Ans. Water that does not endanger our health in any way when we drink it is called safe drinking water or potable water.

2.   Name the instrument used for looking at micro

organisms?

Ans. Micro-scope is used for looking at micro-organisms.

3.   What is settling?

Ans. The process of allowing heavier particles to settle to the              bottom of still water is called settling.

4.    What steps can be taken to take care of drinking water?

Ans. a)We can keep drinking water containers covered.

         b) making use of a dipper to take out water.

         c) we must put a tap on the container to take water.

         d) we must wash the container well before refilling                       water.

II. Classify the following substances accordingly:

   1.   Syrup       Plastic bottle      iron nail                      oil

   2.  Leaf         honey                  sand                      brick

   3.  coin          ball                       lemon juice            shells

Substances that dissolve	Substances that do not dissolve	Substances that float	Substances that sink
1.   Syrup	Oil	Plastic bottle	Iron nail
2.  honey	Sand	Leaf	Brick
3.  lemon juice	Shells	Ball	Coin

III. Distinguish between:

1. Soluble and Insoluble substances

Soluble substances	Insoluble substances
1. Substances which dissolve in water are known s soluble substances	1. Substances which do not dissolve in water are known s soluble substances
2. Example – sugar, salt	2. Example – wood, stone