During dehydration of alcohols to alkenes by heating with concentrated H2SO4

• Hydrocarbons
• Organic Oxygen

During dehydration of alcohols to alkenes by heating with concentrated H₂SO₄ the initiation step is

1. protonation of alcohol molecule
2. formation of an ester
3. formation of carbocation
4. elimination of water

Answer

Dehydration of alcohol to alkene in presence of concentrated H₂SO₄ involves the –OH group in the alcohol that donates two electrons to H⁺ from the acid reagent, forming an alkyloxonium ion. The deprotonated acid (the nucleophile) then attacks the hydrogen adjacent to the carbocation and form a double bond.

Thus, the initiation step is protonation of alcohol.

The correct option is A.