A pure white crystalline compound was found to melt at 131.5-132.0°C when taken on a melting point apparatus, and on further heating, the liquid was found to start bubbling at ca 155-160 °C. The capillary containing the melted compound was set aside to cool, and resolidify. When the sample was retried using that same capillary, the sample melted at 120.6-154.5°C, along with some bubbling. What is the cause of the bubbles? Why is the melting point so wide the second time? Explain by stating what you have learned in this laboratory about melting points.

A pure white crystalline compound was found to melt at 131.5-132.0°C when taken on a melting point apparatus, and on further heating, the liquid was found to start bubbling at ca 155-160 °C. The capillary containing the melted compound was set aside to cool, and resolidify. When the sample was retried using that same capillary, the sample melted at 120.6-154.5°C, along with some bubbling. What is the cause of the bubbles? Why is the melting point so wide the second time? Explain by stating what you have learned in this laboratory about melting points.

Macroscale and Microscale Organic Experiments

7th Edition

ISBN:9781305577190

Author:Kenneth L. Williamson, Katherine M. Masters

Publisher:Kenneth L. Williamson, Katherine M. Masters

Chapter4: Recrystallization

Section: Chapter Questions

Problem 6Q

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