Which reagent hydrates an alkene to form an alcohol?

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Multiple Choice

Which reagent hydrates an alkene to form an alcohol?

Hydration of an alkene occurs when water adds across the carbon–carbon double bond in the presence of a strong acid. The acid donates a proton to the double bond, generating a more reactive intermediate that water can attack. After water adds, the molecule is deprotonated to form the alcohol, and the acid catalyst is regenerated. Concentrated sulfuric acid is the best choice because it provides a strong, effective acid to protonate the alkene and drive the electrophilic addition in the catalytic cycle. Water alone won’t promote the reaction at a useful rate, hydrogen gas would lead to hydrogenation rather than hydration, and sodium hydroxide would neutralize the acid and prevent the necessary protonation step.

Hydration of an alkene occurs when water adds across the carbon–carbon double bond in the presence of a strong acid. The acid donates a proton to the double bond, generating a more reactive intermediate that water can attack. After water adds, the molecule is deprotonated to form the alcohol, and the acid catalyst is regenerated.

Concentrated sulfuric acid is the best choice because it provides a strong, effective acid to protonate the alkene and drive the electrophilic addition in the catalytic cycle. Water alone won’t promote the reaction at a useful rate, hydrogen gas would lead to hydrogenation rather than hydration, and sodium hydroxide would neutralize the acid and prevent the necessary protonation step.

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