Which of the following pairs of compounds correctly represent functional isomerism? — Isomerism and Stereochemistry Chemistry Question

💡 Solution & Explanation

In IUPAC classification, $1^\circ$, $2^\circ$, and $3^\circ$ amines/amides are treated as entirely different functional groups. Thus, propanamide ($1^\circ$) and N-methylethanamide ($2^\circ$) are functional isomers. Propanal (an aldehyde) and propanone (a ketone) are also classic functional isomers. By contrast, 1-propanol and 2-propanol are merely positional isomers of the exact same functional group.