Macroscale and Microscale Organic Experiments
Macroscale and Microscale Organic Experiments
7th Edition
ISBN: 9781305577190
Author: Kenneth L. Williamson, Katherine M. Masters
Publisher: Brooks Cole
Question
Book Icon
Chapter 4, Problem 1Q
Interpretation Introduction

Interpretation:

The gray color of the naphthalene obtained after the usual purification procedure should be explained.

Concept introduction:

Recrystallization is a technique that is used to purify the impure compounds. It is based on the principle that the solubility of substances increases with the increase in temperature.

Following are some of the types of recrystallization:

  1. Single-solvent recrystallization
  2. Multi-solvent recrystallization
  3. Hot filtration-recrystallization

Expert Solution & Answer
Check Mark

Answer to Problem 1Q

The gray color of naphthalene is due to the impurity of charcoal.

Explanation of Solution

The change in color of naphthalene indicates the presence of an impurity in it. But this impurity neither lowers the melting point of the sample nor widens the melting point range. So this is not a normal small-sized impurity and it shows only color change in the sample. The color of the sample changes from white to gray so the impurity may be charcoal (black) that is used in the recrystallization process.

Conclusion

Due to the impurity of charcoal, naphthalene found to have grayish color.

Want to see more full solutions like this?

Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!
Students have asked these similar questions
Draw a FIVE STEP Schematic diagram of the procedure on how to separate pure crystals of CuSO4 , Alum and Benzoic acid. (Draw only ONE schematic diagram for the three samples)
The method of extraction for Roman chamomile is: Choose one answer. a. cold-press extraction b. steam distillation c. water distillation d. solvent extraction
If 80% of a desired compound is extracted into the organic phase in each step (leaving 20% in the aqueous layer), how many extractions are necessary to ensure that at least 99% of the compound has been recovered in the organic phase?      1 extraction     2 extractions     3 extractions     4 extractions
Knowledge Booster
Background pattern image
Similar questions
SEE MORE QUESTIONS
Recommended textbooks for you
Text book image
Macroscale and Microscale Organic Experiments
Chemistry
ISBN:9781305577190
Author:Kenneth L. Williamson, Katherine M. Masters
Publisher:Brooks Cole
Text book image
EBK A SMALL SCALE APPROACH TO ORGANIC L
Chemistry
ISBN:9781305446021
Author:Lampman
Publisher:CENGAGE LEARNING - CONSIGNMENT