Concept explainers
The amino acid
(S)-alanine
a. What is the melting point of
b. How does the melting point of a racemic mixture of
c. What is the specific rotation of
d. What is the optical rotation of a racemic mixture of
e. Label each of the following as optically active or inactive: a solution of pure
(a)
Interpretation: The melting point of
Concept introduction: Enantiomers are the stereoisomers that have exactly opposite
Answer to Problem 5.27P
The melting point of
Explanation of Solution
The given melting point of
The melting point of
(b)
Interpretation: The melting point of a racemic mixture of
Concept introduction: Enantiomers are the stereoisomers that have exactly opposite
Answer to Problem 5.27P
The melting point of a racemic mixture of
Explanation of Solution
The given melting point of
Therefore, the melting point of a racemic mixture of
The melting point of a racemic mixture of
(c)
Interpretation: The specific rotation of
Concept introduction: Enantiomers are the stereoisomers that have exactly opposite
Answer to Problem 5.27P
The specific rotation of
Explanation of Solution
The specific rotation of
Thus, the specific rotation of
The specific rotation of
(d)
Interpretation: The optical rotation of a racemic mixture of
Concept introduction: Enantiomers are the stereoisomers that have exactly opposite
Answer to Problem 5.27P
The optical rotation of a racemic mixture of
Explanation of Solution
The specific rotation of
The specific rotation of
The
Thus, the optical rotation of a racemic mixture of
The optical rotation of a racemic mixture of
(e)
Interpretation: The solutions of pure
Concept introduction: Enantiomers are the stereoisomers that have exactly opposite
Answer to Problem 5.27P
The pure
Explanation of Solution
The pure
A racemic mixture is obtained when
A
Thus, the pure
The pure
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