A solid mixture contains four constituents P, Q, R and S.P consists of tiny grains and it is mixed with cement for plastering the walls. Q is a white solid which is recovered on a large scale from sea water by the process of evaporation. R is in the form of tiny particles of a material whose corrosion is called rusting. And S is a white solid which is used in making ordinary dry cells.(a) What could P, Q, R and S be?(b) How would you separate a mixture containing P, Q, R and S?
(a) P consists of tiny grains and it is mixed with cement for plastering the walls. Hence, P could be sand.
Q is a white solid, that is recovered on a large scale from seawater by the process of evaporation. It is common salt.
R is in the form of tiny particles of materials, whose corrosion is called rusting. It is, iron filings.
S is ammonium chloride.
(b) The mixture of P, Q, R, and S is taken
- To separate R (iron filings) by using a magnet to attract them.
- Then separate S (ammonium chloride) by sublimation.
- On shaking P (sand) and Q (common salt) with water. The mixture is then filtered.
- Sand is obtained as residue.
- Now, we will evaporate the filtrate to dryness to obtain Q (common salt).
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