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Is Matter Around Us Pure? — Science STD 9 — Question

CBSE BoardEnglish MediumSTD 9ScienceIs Matter Around Us Pure?3 Marks
Question
Which method is better for recovering sugar from sugar solution: evaporation or crystallization? Give reason for your answer.
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Answer

Crystallisation is better method for recovering sugar from sugar solution than evaporation because:
  1. Sugar decomposes or get charred on heating to dryness during evaporation. There is no such problem in crystallization.
  2. The soluble impurities do not get removed in the process of evaporation. But such impurities get removed in crystallization.

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