Write the IUPAC name of the following : CH3−CH2−CH=CH−O∥C−H

As it is having five carbons in chain then word pent is used. A double bond is present at 2 position from the aldehyde group given the name 2−en. The functional group is aldehyde (CHO) and the IUPAC name for aldehyde is −al. So, the name of the compound is Pent−2−enal