Question
Explain the term ‘sieving’. State the structure of a sieve and explain the separation of different sized particles by sieving.
✓
Answer
Sieving— is a method of separation, which is used for separating substances of different sizes that cannot be separated in handpicking.
Principle— Based on the difference in the size of the solid particles
The technique of Separation— The large-sized particles are separated from the small or finer particles by passing the mixture through a sieve. The sieve has a wooden frame, with a metal mesh at its base. The mixture is added from the top of the sieve when the larger particles stay above and the finer particles collect below it on shaking the sieve.
Examples— Separation of rice powder from the soil, separation of different sized particles of diamond, and of sand.
Principle— Based on the difference in the size of the solid particles
The technique of Separation— The large-sized particles are separated from the small or finer particles by passing the mixture through a sieve. The sieve has a wooden frame, with a metal mesh at its base. The mixture is added from the top of the sieve when the larger particles stay above and the finer particles collect below it on shaking the sieve.
Examples— Separation of rice powder from the soil, separation of different sized particles of diamond, and of sand.
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