Laboratory Techniques in Organic Chemistry
4th Edition
ISBN: 9781464134227
Author: Jerry R. Mohrig, David Alberg, Gretchen Hofmeister, Paul F. Schatz, Christina Noring Hammond
Publisher: W. H. Freeman
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Chapter 15, Problem 7Q
Interpretation Introduction
Interpretation:
The reason for methanol and pentane to be an awkward solvent pair 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 hot solvent is essential and in cold solvent the solubility should be minimum for 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 solvent for recrystallization 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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