MHT CET Chemistry Question (2026) — Solution

Step-by-step solution

The molecular formula C _3 H _9 N corresponds to saturated acyclic amines. The possible structural isomers are: Primary (1^ ) amines: CH _3 CH _2 CH _2 NH _2 (propan-1-amine) and CH _3 CH ( NH _2) CH _3 (propan-2-amine). Secondary (2^ ) amine: CH _3 CH _2 NHCH _3 (N-methylethanamine). Tertiary (3^ ) amine: ( CH _3)_3 N (N,N-dimethylmethanamine). A quaternary ammonium salt requires the nitrogen atom to be bonded to four alkyl groups. The simplest quaternary ammonium salt is the tetramethylammonium ion, which contains four carbon atoms ( C _4 H _ 12 N ^+). Thus, C _3 H _9 N cannot represent a quaternary ammonium salt. Answer: quaternary ammonium salt