Interpretation:
The effect of the rate of crystal growth on the purity of a recrystallized compound should be determined.
Concept introduction:
Recrystallization is a process in which an impure crystalline solid dissolved in hot solvent precipitates back when the solvent is cooled and that leads to formation of pure solid crystals. For successful recrystallization, maximum solubility of solute in the hot solvent is essential and in the cold solvent the solubility should be minimumfor the maximum yield of crystals.
If solute will have good solubility in cold solvent, there will be loss of compound on recrystallization. To minimize this loss, the choice of the recrystallization solvent is important.
When a solute is dissolved in an appropriate solvent at an appropriate rate, temperature and concentration then it results in the formation of perfect crystal.
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Laboratory Techniques in Organic Chemistry
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