JEE Main · 2023 · 25 Jan 2023 · Shift 2 · General Organic Chemistry

Propan-1-amine is a primary amine and N-methylethanamine a secondary amine of the same molecular formula, differing in the type of amino function, so they are functional isomers. Hexan-2-one and hexan-3-one are both ketones of the same formula but bear different alkyl groups on the two sides of the carbonyl, which makes them metamers. Ethanamide and its hydroxyimine form interconvert by migration of a hydrogen between the amide and imino arrangements, so they are tautomers. ortho- and para-nitrophenol differ only in the position of the nitro group on the ring, so they are positional isomers. The correct matching pairs propanamine and N-methylethanamine with functional isomers, the two hexanones with metamers, ethanamide and hydroxyethanimine with tautomers, and the nitrophenols with positional isomers.