Question

What are the essential conditions for optical isomerism?

Answer 1

Hint: As we know that the optical isomers are those two compounds that contains the same number of atoms having similar kinds of elements and bonds within the same atom but there is different arrangement of atoms which is non- superimposable mirror image and this property is called optical isomerism.

Complete answer: As we know that isomers are the compounds that possess the same molecular formula but have different arrangement of atoms and their bonds. And the optical isomerism which is basically a property of compounds displaying identical characteristics in terms of chemical and physical properties but differ in their orientation and rotation of polarised light.
So, the essential conditions for optical isomerism are as follows:
I.The compounds should be non-superimposable mirror images of each other.
II.They should possess similar molecular formulas as well as similar structural formulas.
III.The compound must possess an asymmetric carbon atom which is bonded to four different groups of atoms or molecules which is normally called chiral carbon.
IV.The compound can rotate the plane of polarised light.
Also, the two optical isomers or compounds are called enantiomers and the common example is amino acid alanine which exists as D-alanine and L-alanine.

Note: Remember that optical isomers do not possess a plane of symmetry and the two optical isomers are optically active only when they possess a chiral carbon. Two isomers having different arrangement as dextrorotatory and levorotatory are called enantiomers and if these enantiomers are present in equal composition then the resultant is called a racemic mixture.