**QUESTION 3**The (+) enantiomer of Aromatisse has a specific rotation of +21.5. What is the percent of the (-) enantiomer in a mixture, if the specific rotation of the mixture is -15.05?**Explanation:**To solve this problem, one must understand the concept of specific rotation and the calculation of enantiomeric excess.**Specific Rotation Calculation:**Specific rotation is the measure of the degree to which a compound can rotate plane-polarized light. The formula to determine the specific rotation of a mixture of enantiomers is:\[ \left[ \alpha \right]_{\text{mixture}} = f(+) \left[ \alpha \right]_{(+)} + f(-) \left[ \alpha \right]_{(-)} \]where \(\left[ \alpha \right]_{\text{mixture}}\) is the specific rotation of the mixture, \(f(+)\) is the fraction of the (+) enantiomer, \(\left[ \alpha \right]_{(+)}\) is the specific rotation of the pure (+) enantiomer, \(f(-)\) is the fraction of the (-) enantiomer, and \(\left[ \alpha \right]_{(-)}\) is the specific rotation of the pure (-) enantiomer.Since the specific rotation of the pure (-) enantiomer is equal in magnitude but opposite in sign to that of the pure (+) enantiomer,\[ \left[ \alpha \right]_{(-)} = -\left[ \alpha \right]_{(+)} \]Therefore,\[ \left[ \alpha \right]_{\text{mixture}} = f(+) \left[ \alpha \right]_{(+)} - f(-) \left[ \alpha \right]_{(+)} \]Given:- \(\left[ \alpha \right]_{\text{mixture}} = -15.05\)- \(\left[ \alpha \right]_{(+)} = +21.5\)Applying the enantiomeric excess formula and considering \(f(+) + f(-) = 1\), the calculation can determine the fraction of the (-) enantiomer. Subsequently, convert the fraction to a percentage.This specific problem could be solved in a thorough explanation to support student comprehension of the enantiomeric excess

Specific rotation of (+) enantiomer = +21.5 Specific rotation of mixture = -15.05 Percent of (-)…

Answered: The (+) enantiomer of Aromatisse has a…

The (+) enantiomer of Aromatisse has a specific rotation of +21.5. What is the percent of the (-) enantiomer in a mixture, if the specific rotation of the mixture is -15.05?

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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