Class VI

Chemistry

Chapter 5: Separation of substances

Project: Water purification

Fill about ¼th of a big bowl with water

Add dye or food colouring to the water and mix thoroughly(this represents the dirty water)

Place a small cup in the middle of the jar

Cover the bowl with a plastic sheet making sure it is tightly sealed and that there are no holes.

Place a heavy object in the middle, an eraser would do

After a day or two remove the plastic

The small cup should have clear water inside, ready to drink

This works because when water evaporates, it sticks to the plastic in form of moisture and drips down clean into small cup. Water in cup is clean because only water evaporated and not the impurities (in this the color)