How to seprate a solid from …

1. Hand picking: This method is usually used to separate undesirable substances such as small pieces of stones from wheat, rice and pulses.

2. Threshing: The process in which stalks are beaten to separate grains from the stalks, and from the chaff that covers the grains is called threshing. This method of separation is based on the fact the stalks of the crop plants and the chaff are soft materials so can be broken into pieces and the grains are very hard so it remains unaffected.

3. Winnowing: The method of separating husk from grains with the help of wind is called winnowing. This method is based on the fact that the husk is very light and the grains are comparatively heavy.

4. Sieving: Sieving is used to separate those mixtures which have components of different sizes. In this process, the mixture having components of different sizes are put in a sieve and the sieve is moved back and forth continuously. The smaller particles pass through the holes of the sieve and collect in a vessel kept below. The bigger particles remain behind in the sieve.