Answer: Acetic acid.
- A Methane
- B Acetic acid
- C Ethene
- D Propanol
Correct answer: B. Acetic acid
Explanation: Strong oxidation of ethanol by acidified KMnO4 produces acetic acid.
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.