The question is: A student preforms a crystallization on an impure sample of biphenyl. The sample weighs 0.5g and contains about 5% impurity. Based on his knowledge of solubility, the student decides to use benzene as the solvent. After crystallization, the crystals are dried and the final weight is found to be 0.02g. Assume that all steps in the crystallization are performed correctly, there are no spills, and the student lost very little solid on any glassware or in any of the transfers. Why is the recovery so low? I know it’s becsuse the benzene wasn’t a good choice for the solvent but I can’t explain why. Thank you!

The question is: A student preforms a crystallization on an impure sample of biphenyl. The sample weighs 0.5g and contains about 5% impurity. Based on his knowledge of solubility, the student decides to use benzene as the solvent. After crystallization, the crystals are dried and the final weight is found to be 0.02g. Assume that all steps in the crystallization are performed correctly, there are no spills, and the student lost very little solid on any glassware or in any of the transfers. Why is the recovery so low? I know it’s becsuse the benzene wasn’t a good choice for the solvent but I can’t explain why. Thank you!

EBK A SMALL SCALE APPROACH TO ORGANIC L

4th Edition

ISBN:9781305446021

Author:Lampman

Publisher:Lampman

Chapter80: Crystallization: Purification Of Solids

Section: Chapter Questions

Problem 4P

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