Statement I: Metamerism arises due to different alkyl chains on either side of a polyvalent functional group. In ketones, the carbonyl group (>C=O) acts as the polyvalent functional group. In 2,6-diethylcyclohexanone, the alkyl groups attached to the α-carbons are two ethyl groups. In 6-methyl-2-n-propylcyclohexanone, the alkyl groups are a methyl group and an n-propyl group. Since the alkyl groups around the carbonyl group are different while the molecular formula remains the same, they are metamers. Thus, Statement I is true.
Statement II: For a ketone to exhibit keto-enol tautomerism, it must have at least one α-hydrogen atom. In 2,2,6,6-tetramethylcyclohexanone, the α-carbons (C2 and C6) are bonded to two methyl groups each. Since there are no α-hydrogen atoms present, it cannot undergo keto-enol tautomerism. Thus, Statement II is false.
Answer: Statement I is true but Statement II is false