Concept explainers
(a)
Interpretation:
The specific rotation of pure chiral compound
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 as 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 as,
Answer to Problem 6.10P
The specific rotation of pure chiral compound
Explanation of Solution
The molarity of the solution of
The observed rotation of the solution of
The path length is
The molecular mass of the compound
Therefore, the molar mass of the compound
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 the compound
Substitute the value of
Therefore, the specific rotation of pure chiral compound
The specific rotation of pure chiral compound
(b)
Interpretation:
The observed rotation of the given solution, that is formed with an equal volume 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 as asymmetric or stereogenic centers. A chiral molecule is an optically active molecule. It rotates the plane of a plane polarized light. The observed optical rotation of a compound is given as,
Answer to Problem 6.10P
The observed rotation of the given solution is zero.
Explanation of Solution
It is given that two enantiomeric solutions of same molarity are mixed with same volume. The resulting solution is a racemic mixture. The specific rotation of two enantiomers is the same in magnitude but different in sign. The specific rotation of both enantiomers will cancel each other. Therefore, the observed rotation of the given solution is zero.
The observed rotation of the given solution is zero.
(c)
Interpretation:
The observed rotation of the given solution that is formed by dilution of corresponding solution 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 as asymmetric or stereogenic centers. A chiral molecule is an optically active molecule. It rotates the plane of a plane polarized light. The observed optical rotation of a compound is given as,
Answer to Problem 6.10P
The observed optical rotation of the given solution is
Explanation of Solution
The molarity of the solution of
The observed rotation of the solution of
The path length is
The molecular mass of the compound
Therefore, the molar mass of the compound
The specific rotation of pure chiral compound
It is given that the solution of
The solutions are mixed in equal volume. Therefore, the molarity of new solution is calculated as
Where,
•
•
Substitute the value of
The molarity of the solution can be converted into the concentration by multiplying the molar mass of the compound
The observed optical rotation of a compound is given as,
Where,
•
•
•
Substitute the value of
Therefore, the observed optical rotation of the given solution of
The observed optical rotation of the given solution is
(d)
Interpretation:
The specific rotation 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 as asymmetric or stereogenic centers. A chiral molecule is an optically active molecule. It rotates the plane of a plane polarized light. The observed optical rotation of a compound is given as,
Answer to Problem 6.10P
The specific rotation of
Explanation of Solution
The path length is
The concentration of the given solution of
The observed optical rotation of the given solution of
The specific optical rotation of a compound is given as,
Where,
•
•
•
Substitute the value of
Therefore, the specific rotation of
The specific rotation of
(e)
Interpretation:
The specific rotation 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 as asymmetric or stereogenic centers. A chiral molecule is an optically active molecule. It rotates the plane of a plane polarized light. The observed optical rotation of a compound is given as,
Answer to Problem 6.10P
The specific rotation of
Explanation of Solution
Enantiomers are the non-superimposable mirror images of each other. Therefore, the magnitude of the specific rotation of enantiomers of the given compound is same but the sign of specific rotation is different. The specific rotation of
Therefore, the specific rotation of
The specific rotation of
(f)
Interpretation:
The observed rotation 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 as asymmetric or stereogenic centers. A chiral molecule is an optically active molecule. It rotates the plane of a plane polarized light. The observed optical rotation of a compound is given as,
Answer to Problem 6.10P
The observed optical rotation of the given solution is
Explanation of Solution
The molecular mass of the compound
Therefore, the molar mass of the compound
The specific rotation of pure chiral compound
The given solution contains
The volume of the given solution is
The solution formed by
The molarity of the solution is represented as,
Where,
•
•
Substitute the value of
The molarity of the solution can be converted into the concentration by multiplying the molar mass of the compound
The observed optical rotation of a compound is given as,
Where,
•
•
•
Substitute the value of
Therefore, the observed optical rotation of the given solution is
Therefore, the observed optical rotation of the given solution is
(g)
Interpretation:
The enantiomeric excess
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 as asymmetric or stereogenic centers. A chiral molecule is an optically active molecule. It rotates the plane of a plane polarized light. The enantiomeric excess of a sample is given as,
Answer to Problem 6.10P
The enantiomeric excess
Explanation of Solution
The given solution contains
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
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