MHT CET Chemistry Question (2026) — Solution

Step-by-step solution

The given reaction is a Wurtz reaction, which involves the coupling of two alkyl halide molecules in the presence of sodium and dry ether to form a symmetrical alkane. The structure of the product, 3,4-diethyl-3,4-dimethylhexane, is: CH _3 -CH _2 -C(CH _3 )(CH _2 CH _3 )-C(CH _3 )(CH _2 CH _3 )-CH _2 -CH _3 Since the Wurtz reaction produces a symmetrical alkane by the dimerization of alkyl radicals, we can determine the structure of the reactant by cleaving the central carbon-carbon bond of the product. Cleaving the bond between C3 and C4 yields two identical radicals: CH _3 -CH _2 -C ^ (CH _3 )(CH _2 CH _3) The corresponding alkyl halide substrate 'S' is formed by attaching a halogen (e.g., chlorine) to the radical carbon: CH _3 -CH _2 -C(Cl)(CH _3 )-CH _2 -CH _3 The longest carbon chain has 5 carbon atoms. Numbering the chain from either side gives the same locants, with a chloro group and a methyl group at the 3rd carbon. Thus, the IUPAC name of the substrate 'S' is 3-chloro-3-methylpentane. Answer: 3 - chloro - 3 - methylpentane