Question

What is optical isomerism? What do you look for to determine whether an organic compound exhibits optical isomerism?1-bromo-1-chloroethane is optically active, whereas 1-bromo-2-chloroethane is not optically active. Explain.

Short answer

Optical isomerism is when two compounds contain the same number and types of atoms, bonds, but different spatial arrangement of atoms. To be optically active, a compound must have at least one chiral carbon atom with four different substituents. 1-bromo-1-chloroethane is optically active because it has one chiral carbon atom

Step-by-step solution

Definition of optical isomerism

Optical isomerism is when two compounds contain the same number and types of atoms, bonds, but different spatial arrangement of atoms. These compounds have non-overlapping mirror images and are optically active because they rotate the plane of polarized light.

To determine whether the compound has optical isomers, we have to determine if the compound has chiral carbon atoms. These types of atoms have attached four different substitutes to the atom and this is how we are going to determine optical isomers.

1-bromo-1-chloroethane is optically active because it has one chiral carbon atom. 1-bromo-2-chloroethane is not optically active because it does not have an atom with four different substitutes.

To Explain optically active and not optically active

To Explain of 1-bromo-1-chloroethane is optically active, whereas 1-bromo-2-chloroethane is not optically active

Hence Optical isomerism is when two compounds contain the same number and types of atoms, bonds, but different spatial arrangement of atoms. To be optically active, a compound must have at least one chiral carbon atom with four different substituents. 1-bromo-1-chloroethane is optically active because it has one chiral carbon atom.