Chemistry - STEREO ISOMERISM Question with Solution | TestHub

Question Explanation: Calculating the total number of enantiomeric pairs for 1-bromo-2chlorocyclohexane.

Concept: Stereoisomers and enantiomeric pairs for disubstituted cycloalkanes.

Solution: 1-bromo-2-chlorocyclohexane is an unsymmetrical disubstituted cyclohexane with two chiral centres ( ${\mathrm{C}}_1$ and ${\mathrm{C}}_2$ ).

The total number of stereoisomers is $2^n$, where $n=2$, so $2^2=4$ stereoisomers.

These 4 stereoisomers consist of two pairs of enantiomers:

1. cis form: A pair of enantiomers (chiral).

2. trans form: A pair of enantiomers (chiral).

Total enantiomeric pairs = 2. Final Answer: (2)