Water and air are two materials which form a very important part of our lives.
Water and its properties:
Water has certain characteristics which are called properties. Water can be poured from one container into another.
We have noticed that when a tumbler full of water tilts over on the table then water spills out and falls to the ground.
Water always flows from a higher level to a low level.
Imagine the scenery of a waterfall. Imagine the scenery of the water in a river. Water always flows from a higher level to a lower level.
Like water, other liquids can also be poured. Petrol, at the petrol pump is filled from their tank into our car or scooter.
We observed this many times, our mother pours cooking oil
from the can into the cooking pan.
Liquids can be poured from one container into another.
They flow from higher to lower level.
Another interesting property of water is that, it dissolves many solids.
For example, let us dissolve a teaspoon each of salt and sugar in two different glasses of water.
Does the solids (salt and sugar) dissolved and mixed with the water. Taste each of them. We will get the taste of salt and sugar.
Now mix some mango squash in a glass of water and mix some orange squash in another glass and then we can check the taste of both the glass. Water takes on the taste of the substance dissolved in it.
Take three small containers with warm water in them. Take red, green and blue water colors. Dissolve each of these colors in separate containers.
We observe that the color of water in each container look different. Water looks red, green and blue in different containers.
Water takes on the color of the substance dissolved in it.
Air and its properties:
Air too, has characteristics similar to that of water. Air mixes with different gases and takes on their color. We know air is made up of different gases. These gases are nitrogen, oxygen, carbon dioxide and various other gases.
We cannot see air. We can only feel it as in a breeze. Similarly, we cannot see the different gases. We only know or feel that they are there.
Some gases have characteristic smell. When we switch on the gas burner, we get the smell of the cooking gas.
Soon this gas will mix with air. So we can say that different gases can mix with air.
We have seen smoke from a fire rise into the air. The smoke from fire burning is grey or black in color. When it rises into the air, the air, too, becomes dark in color.
Therefore, we can say that air takes on the color of different gases.
These are the basic characteristics and properties of water and air which form a very important part of our lives.