See image — IUPAC and Nomenclature Chemistry Question

💡 Solution & Explanation

Step 1: Identify the functional group. The compound contains a —CHO group (formyl group) attached to a nitrogen atom, which makes it an amide (specifically a formamide derivative). The N—H is replaced by N—CH3, indicating N-substitution. Step 2: Identify the parent chain. The carbonyl carbon (CHO) has only one hydrogen and is bonded to nitrogen, so the parent acid would be methanoic acid (formic acid, HCOOH). The corresponding amide is methanamide (formamide, HCONH2). Step 3: Identify the substituent on nitrogen. The nitrogen bears a methyl group (CH3), so this is N-methyl substituted methanamide. Step 4: Construct the IUPAC name. The parent amide is methanamide, and the N-methyl substituent gives N-methylmethanamide. Step 5: Why not other names? It is not dimethylamine (no carbonyl), not acetamide (that would be CH3CONH2), and not N-methylacetamide (that would require a two-carbon acyl group). The single-carbon formyl group confirms methanamide as the parent. Therefore, the correct answer is N-methylmethanamide.