Answer: C n H 2n+2 O.
- A C<sub>n</sub>H<sub>2n</sub>O
- B C<sub>n</sub>H<sub>2n-2</sub>O
- C C<sub>n</sub>H<sub>2n+2</sub>O
- D C<sub>n</sub>H<sub>2n+1</sub>O<sub>2</sub>
Correct answer: C. C<sub>n</sub>H<sub>2n+2</sub>O
Explanation: A saturated alcohol adds one O to an alkane, so its formula is C<sub>n</sub>H<sub>2n+2</sub>O.
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.