EVERYDAY SCIENCE

Detailed explanation-1: -2-chlorobutane exhibits optical isomerism because it contains chiral carbon atom. A chiral centre in an organic compound is a carbon atom directly connected to four different groups.

Detailed explanation-2: -Chiral And Achiral Molecules Such a molecule is known as a chiral molecule. If all the group attached to the central carbon atom are not different then there exist plane of symmetry. Such molecules are called achiral molecules. It is clear that only molecule having chiral centre will show optical isomerism.

Detailed explanation-3: -Therefore there is one stereogenic carbon in the molecule and exhibits optical isomerism and they possess non-superimposable mirror image. Therefore, only 2-bromobutane exhibits optical isomerism.

Detailed explanation-4: -2-bromobutane is a chiral molecule as it contains an asymmetric carbon atom therefore, it is optically active whereas 1-bromobutane is an achiral molecule as it does not contain an asymmetric carbon atom therefore it is optically inactive.