Final answer:
Butan-2-ol can be prepared by direct hydration of but-2-ene using 50% sulfuric acid as a catalyst, following Markovnikov's rule. Other alcohols listed arise from different alkene precursors or give primary/tertiary alcohols, which are less likely to form in such hydration reactions. Option number b is correct.
Step-by-step explanation:
Among the alcohols listed, butan-2-ol can be prepared by the direct hydration of the corresponding alkene, which in this case would be but-2-ene, using 50% sulfuric acid as a catalyst. The hydration of alkenes in the presence of an acid catalyst typically produces alcohols where the hydroxyl (-OH) group adds to the more substituted carbon atom, following Markovnikov's rule. Therefore, butan-2-ol is the alcohol that can be directly formed through this process.
Butan-1-ol can also be prepared by the hydration of but-1-ene, but the reaction would be less favorable due to the formation of a primary alcohol versus a secondary alcohol in the case of butan-2-ol. 2-Methylpropan-1-ol and 2-Methylpropan-2-ol(isobutanol or isobutyl alcohol) can derive from 2-methylpropene, but the former involves a less favorable formation of a primary alcohol while the latter would lead to a tertiary alcohol, which is not typically the preferred product in acid-catalyzed hydration reactions.