Answer: 2-methylpropene.
- A But-1-ene
- B But-2-ene
- C 2-methylpropene
- D Ethene
Correct answer: C. 2-methylpropene
Explanation: Dehydration of tert-butanol mainly produces 2-methylpropene.
The phenoxide ion's negative charge spreads into the aromatic ring through resonance, lowering its energy and making phenol give up its proton more easily; an alkoxide ion (from a plain alcohol) has nowhere to delocalise the charge, making alcohols far less acidic.
Concept context
Oxygen-containing organic compounds. Understand the acidic nature of phenols, reactions of alcohols (dehydration, oxidation, esterification), and properties of ethers. Includes industrial applications and named reactions.