A substance which cause pollution is called a

________________ is essential for the growth of plants.

In the ___________, water occurs in oceans, seas, rivers, lakes, ponds, springs, wells etc.

Which  is the process of removing dissolved salts from sea or ocean water?

Sea and ocean water contains large amount of salts and these make the water salty and is called

____________ is used for doing some mechanical work such as running a flour mill, drawing water from a well etc.

Solution of any substance in water is known as

The electricity produced by using the flow of water from a dam is called

Air under pressure is blown into the filtered water. This process is called

___________ is used for removing suspended impurities in water.