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We need to separate substances to get useful ones out from the rest of the materials.
There are several methods of separation
In this method, we use our hands to separate two substances. This method is used to separate stone, dirt and husk from grains like wheat and rice.
Threshing is used to separate grains from their stalks. Before threshing, the stalks are dried in the sun.
In this method, we use Air to separate heavier and lighter particles. Example: Separation of husk from grain is done by winnowing.
This method is used to separate stones, husk, and other dirt material from the flour. When we use a sieve, the smaller particles passes through the holes and bigger particles remain in it.
This method is used to separate insoluble particle like chalk powder and sand from water. When the container having the mixture of sand and water is left undisturbed for a long time, the sand settle at the bottom and the water becomes clear.
In sedimentation, the water which becomes clear is poured into another vessels. This method is known as decantation.
Filtration is used to separate bigger particles from lighter ones. For example: Tea and tea leaves are separated using this method.
Evaporation is the process of converting water into water vapours. It is used to separate soluble particles from water. Example: to separate salt from seawater this method is used.
The conversion of water vapour into water is called condensation.
When no more space is left to dissolve particles in water, it becomes saturated and this solution is called a saturated solution.