See image — Hydrocarbons Chemistry Question

💡 Solution & Explanation

Concept: Ozonolysis cleaves C=C double bonds, converting each carbon of the double bond into a carbonyl group. To obtain acetone (CH3)2C=O as a product, we need a double bond where one carbon bears two methyl groups, i.e., a (CH3)2C= unit in the starting alkene. Step 1: Identify what structural feature gives acetone upon ozonolysis. Acetone is (CH3)2C=O. For this to form from ozonolysis, the starting material must contain a =C(CH3)2 fragment — that is, a carbon in the double bond that carries two methyl groups. Step 2: Analyze option (d). Option (d) is 1-(propan-2-ylidene)cyclohexane, which is cyclohexane with an exocyclic double bond to C(CH3)2, i.e., the structure is cyclohexane=C(CH3)2. The double bond carbon outside the ring is C(CH3)2. Upon ozonolysis, this double bond is cleaved to give: - Cyclohexanone (from the ring carbon) - Acetone, (CH3)2C=O (from the exocyclic =C(CH3)2 carbon) Thus option (d) directly contains the =C(CH3)2 unit and gives acetone as one product. Step 3: Why other options fail. (a) The structure shown is a diene but the terminal carbon with two substituents does not form a (CH3)2C= unit at the correct position to yield acetone directly from a single double bond cleavage. (b) Similarly, option (b) does not have a =C(CH3)2 fragment; it lacks two methyl groups on the same double-bond carbon. (c) Option (c) appears to be a structure like 2-methylbut-1-ene or similar; while it may have a branched carbon, the arrangement does not provide a =C(CH3)2 unit that would yield acetone. Step 4: Conclusion. Only option (d), with its exocyclic isopropylidene group (=C(CH3)2), contains the necessary =C(CH3)2 unit that upon ozonolysis yields acetone as one of the products. Therefore, the correct answer is D.