The goal of the recrystallization procedure is to obtain purified materlal with a maximized recovery. Which of the following will lower the percent recovery? . In the solution step, an unnecessarily large volume of solvent is used. 11. The crystals obtalned after filtration are not washed with fresh cold solvent before drying I. The crystals referred to in (I) are washed with fresh hot solvent. IV. Crystallization is accelerated by Immediately placing the flask of hot solution In an ice-water bath. V. A large quantity of decolorizing carbon is used.

The goal of the recrystallization procedure is to obtain purified materlal with a maximized recovery. Which of the following will lower the percent recovery? . In the solution step, an unnecessarily large volume of solvent is used. 11. The crystals obtalned after filtration are not washed with fresh cold solvent before drying I. The crystals referred to in (I) are washed with fresh hot solvent. IV. Crystallization is accelerated by Immediately placing the flask of hot solution In an ice-water bath. V. A large quantity of decolorizing carbon is used.

EBK A SMALL SCALE APPROACH TO ORGANIC L

4th Edition

ISBN:9781305446021

Author:Lampman

Publisher:Lampman

Chapter2: Crystallization

Section: Chapter Questions

Problem 3Q

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In fractional distillation, liquid can be seen running from the bottom of the distillation column back into the distilling flask. What effect does this returning condensate have on the fractional distillation?
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During recrystallization process, if your solution has come to room temperature and no crystals have formed, which of the following methods you can employ to entice crystals to grow. i. By adding more solvent to the solution ii. By scratching on the bottom of flask containing the solution iii. By adding the seed crystals all (i) (ii) and (iii) are correct Only (i) is correct Only (i) and (ii) are correct Only (ii) is correct Only (ii) and (iii) are correct
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