Interpretation:
The specific rotation of enantiopure cholesterol and the fraction of synthetic cholesterol in the given mixture are to be determined.
Concept introduction:
The specific rotation, denoted by
Where
The optical purity is equal to the percentage enantiomeric excess, which can be determined from the following expression:
The percent enantiomeric excess is the difference between the percentages of major and minor enantiomers.
A racemic mixture is the mixture of equal composition of enantiomers.
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