Concept explainers
(a)
Interpretation:
The observed rotation of the
Concept introduction:
A carbon atom that has four nonequivalent atoms or groups attached to it is known as the chiral carbon atom. Chiral carbon centers are also called asymmetric or stereogenic centers. A chiral molecule is an optically active molecule. It rotates the plane of a plane polarized light. The specific optical rotation of a compound is given by the expression as shown below.
Answer to Problem 6.41AP
The observed rotation of the
Explanation of Solution
The molarity of the solution of the
The specific rotation of the
The path length is
The molecular mass of
Therefore, the molar mass of
The specific optical rotation of a compound is given by the expression as shown below.
Where,
•
•
•
The molarity of the solution can be converted into the concentration by multiplying the molar mass of
Rearrange the equation (1) for the value of
Substitute the value of
Therefore, the observed rotation of the
The observed rotation of the
(b)
Interpretation:
The observed rotation of the resultant solution formed by mixture of
Concept introduction:
A carbon atom that has four nonequivalent atoms or groups attached to it is known as the chiral carbon atom. Chiral carbon centers are also called asymmetric or stereogenic centers. A chiral molecule is an optically active molecule. It rotates the plane of a plane polarized light. The specific optical rotation of a compound is given by the expression as shown below.
Answer to Problem 6.41AP
The observed rotation of the resultant solution is
Explanation of Solution
The molarity of the solution of the
When
The specific rotation of the
The specific rotations of two enantiomer are same in magnitude and opposite in sign. Therefore, the specific rotation of the
The path length is
The molecular mass of
Therefore, the molar mass of
The specific optical rotation of a compound is given as,
Where,
•
•
•
The molarity of the solution can be converted into the concentration by multiplying the molar mass of
Rearrange the equation (1) for the value of
Substitute the value of
Therefore, the observed rotation of the resultant solution is
The observed rotation of the resultant solution is
(c)
Interpretation:
The enantiomeric excess of the major enantiomer in the corresponding solution is to be calculated.
Concept introduction:
A carbon atom that has four nonequivalent atoms or groups attached to it is known as the chiral carbon atom. Chiral carbon centers are also called asymmetric or stereogenic centers. A chiral molecule is an optically active molecule. It rotates the plane of a plane polarized light. The specific optical rotation of a compound is given by the expression as shown below.
Answer to Problem 6.41AP
The enantiomeric excess
Explanation of Solution
The solution formed by mixture of
The percentage of
Where,
•
•
Substitute the value of
The enantiomeric excess of a sample is given as,
Substitute the value of percentage of major enantiomer in the above equation.
Therefore, the enantiomeric excess
The enantiomeric excess
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Chapter 6 Solutions
ORGANIC CHEMISTRY SAPLING ACCESS + ETEX
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- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning