Answer: methanol and ethanol.
- A methanol and ethanol
- B propan-1-ol and butan-1-ol
- C methanol and propan-1-ol
- D ethanol and propan-2-ol
Correct answer: A. methanol and ethanol
Explanation: Ethanol has the CH<sub>3</sub>CH(OH)- unit and gives iodoform, while methanol lacks it and does not; the other pairs behave alike.
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.