Water and its impurities

BY-SHALINI UPADHYAY

1. WATER AND ITS IMPURITIES

2. Importance of Water Almost 75 % of earth is covered with water in the form of oceans,rivers,lakes etc. But very less amount of water is potable i.e. fit for human consumption like for drinking,cooking,bathing etc.

3. Water Impurities The substances that pollute water are called ‘Water Impurities’. Water is being polluted by throwing wastes into rivers,oil leakage by water transport etc.

4. Types of Impurities

5. Soluble Impurities Impurities that can be dissolved in water are called Soluble Impurities. Examples are- Salt,any other chemical.

6. Insoluble Impurities Impurities that cannot be dissolved in water are called Insoluble Impurities. Examples- Sand,Mud .

7. Removing Soluble Impurities from water Evaporation It is the process of turning Water into vapours . Distillation The process of purifying water by heating and cooling.

8. Removing insoluble impurities from water Sedimentation Decantation Filtration

9. Definitions of process of removing insolube impurities Sedimentation-The process of settling or being deposited as a sediment. Decantation-It is the process for the separation of mixtures,by removing a layer of liquid,generally one from which a precipitate has settled. Filtration-The process of removing something unwanted from a liquid by using a filter.

10. Purifying drinking water After removing soluble and insoluble impurities,drinking water is purified by two process i.e. ‘Boiling’ and ‘Chlorination’.

11. REFRENCE SLIDE N.C.E.R.T Book Google Images