Concentrated sulfuric acid (cH2SO4) promotes dehydration of an Alcohol to form which product?

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Multiple Choice

Concentrated sulfuric acid (cH2SO4) promotes dehydration of an Alcohol to form which product?

Concentrated sulfuric acid acts as a strong dehydrating agent, pulling water out of the alcohol to form an alkene. The alcohol’s OH is protonated by the acid, turning into a good leaving group as water. When water leaves, a carbocation forms (more common with secondary or tertiary alcohols), and a proton is removed from an adjacent carbon to generate the C=C double bond. More substituted alkenes are typically favored under these conditions. This is dehydration, so the product is an alkene, not a haloalkane or an alcohol; the reverse (hydration) would require adding water to an alkene, which isn’t what this setup does.

Concentrated sulfuric acid acts as a strong dehydrating agent, pulling water out of the alcohol to form an alkene. The alcohol’s OH is protonated by the acid, turning into a good leaving group as water. When water leaves, a carbocation forms (more common with secondary or tertiary alcohols), and a proton is removed from an adjacent carbon to generate the C=C double bond. More substituted alkenes are typically favored under these conditions. This is dehydration, so the product is an alkene, not a haloalkane or an alcohol; the reverse (hydration) would require adding water to an alkene, which isn’t what this setup does.

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