Question

Describe optical isomerism with a suitable example.

Answer 1

1. Compounds having same physical and chemical property but differ only in the rotation of plane of polarised light are known as optical isomers and the phenomenon is known as optical isomerism.
2. Glucose have the ability to rotate the plane of plane polarised light and it is said to be an optically active compound and this property of any compound is called optical activity.
3. The optical isomer which rotates the plane of plane polarised light to the right or in a clockwise direction is said to be dextrorotatory and is denoted by the sign (+).
4. The optical isomer which rotates the plane of plane polarised light to the left or in an anti-clockwise direction is said to be laveo rotatory and is denoted by the sign (-).
5. Dextrorotatory compounds are represented as ‘d’ (or) by (+) sign and leave rotatory compounds are represented as l (or) by (-) sign.
6. The optical isomers which are non-superimposible mirror images of each other are called enantiomers.