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Question

Why is crystallisation technique considered better than simple evaporation to purify solids?

Is matter around us pure CBSE Class 9

June 25, 2024

Answer

Crystallisation is considered better than simple evaporation because

(i) some solids decompose or get charred on heating to dryness.

(ii) some impurities may remain dissolved in the solution even after filtration. On evaporation, these contaminate the solid.

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