Question

What is chain isomerism in relation to organic molecules?

Answer 1

Isomerism:

• It is the phenomenon of the existence of two or more compounds that possess the same molecular formula but different properties.
• Those compounds are called isomers.

Chain isomerism:

• Two or more compounds have similar molecular formulas, but different carbon skeletons/parent chains are known as chain isomers and the phenomenon is termed chain isomerism.

• For example, an organic compound having the molecular formula ${\mathrm{C}}_5{\mathrm{H}}_{12}$ represents three compounds having the same molecular formula ${\mathrm{C}}_5{\mathrm{H}}_{12}$ but different carbon skeletons.
• The chain isomers of ${\mathrm{C}}_5{\mathrm{H}}_{12}$ are shown below in the image.