The correct options are
A Number of optically active compounds formed are 10
B Number of pairs of enantiomers is 5
Lets mark the carbons as shown below:
![](https://search-static.byjusweb.com/question-images/byjus/infinitestudent-images/ckeditor_assets/pictures/466996/original_4an.gif)
(I) Chlorination at 1 or 1' carbon gives an enantiomeric pair.
![](https://search-static.byjusweb.com/question-images/byjus/infinitestudent-images/ckeditor_assets/pictures/467006/original_4an1.gif)
(II) Chlorination at 3 or 3' carbon generates a new chiral centre. Thus, it gives a pair of enantiomers and diastereomers each.
![](https://search-static.byjusweb.com/question-images/byjus/infinitestudent-images/ckeditor_assets/pictures/467010/original_4an2.gif)
(III) Chlorination at 4 or 4' gives a pair of enantiomers.
![](https://search-static.byjusweb.com/question-images/byjus/infinitestudent-images/ckeditor_assets/pictures/467012/original_4an3.gif)
So total compounds formed = 8
All compounds have chiral centres and are optically active.
Enantiomeric pairs = 4
Diastereomeric pairs
=4C2−4=4 Since enantiomers have similar physical properties like boiling point, they can be separated into a single fraction.
Therefore, the number of fractions to separate the mixtures using fractional distillation = 4