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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Question
Chapter 14, Problem 1Q
Interpretation Introduction
Interpretation:
The reason for the broader melting point range observed for second sample should be determined.
Concept introduction:
For a crystalline substance, the temperature at which the substance changes from solid phase to liquid phase is referred to as melting point. Melting point is directly associated with the presence of intermolecular forces like hydrogen bonding, dipole-dipole interactions. High molecular symmetry, large surface area, polarity is related to high melting temperature.
A pure compound melt at a narrow range and compounds with impurities have broad melting temperature. Melting points are obtained by filling the organic compound into the capillary tube with one end sealed.
Expert Solution & Answer
Explanation of Solution
To determine the melting point of a sample the capillary tube is filled with a sample with one end sealed. After that, the sample is heated to a temperature where the solid sample begins to convert into a liquid phase which signifies its melting point.
If too much sample is added to the capillary, the range of melting point becomes broad as more time it takes to melt the whole sample while the temperature of the sample increases with time.
Therefore the sample height of
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A student obtained a solid product in a laboratory synthesis. To verify the identity
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Chapter 14 Solutions
Laboratory Techniques in Organic Chemistry
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