Which compound is an isomer C4H9OH

The Isomers of C₄H₉OH are shown below.

Explanation:

Isomerism is a phenomenon in which the molecules has same molecular formula but different structural formula. Therefore, these compounds are called as isomers of each other.

Isomerism is of different types, i. e.

Functional Group Isomerism:

As shown below, few isomers are Alcohols having - OH functional group, while few are Ethers having - O - functional group. Such isomers which differ in functional groups are called as functional group isomers.

Position Isomers:

In given isomers, Butan-1-ol and Butan-2-ol are called as Position isomers because these compounds are different due to the position of functional group.

Chain Isomers:

In given examples Butan-1-ol and 2-Methylpropan-1-ol are Chain isomers because they differe due to the difference in the chain length. One having a chain of four carbons while other has a chain of three carbons.