Page 6 - REMOVING IMPURITIES FROM WATER AND PURIFYING IT (2)

B. Methods to remove soluble

impurities

1. EVAPORATION

• In evaporation, the water

containing impurities is heated.
After some time, the water

changes into water vapour, leaving
the impurities behind. The water

evaporated can be obtained back
by cooling.

EVAPORATION
•For example, when we take some

water in a vessel and add some
salt to it and heat the mixture, we

will see that all the water has
evaporated from the vessel and the

salt which we dissolved before
heating is left behind in the vessel.

Thus, evaporation can separate a
soluble impurity from water.