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Phenol gives the iodoform test (yellow precipitate) when treated with I₂/NaOH:
AOnly at high temperature
BFalse — phenol does not have a CH₃-C(OH)H- or CH₃CO- group, so iodoform test is negative; ethanol (which has CH₃CH₂OH) DOES give iodoform
CTrue — phenol has CH₃ groups that get oxidised
DOnly in alkaline solution
Answer & Solution
Correct answer: B. False — phenol does not have a CH₃-C(OH)H- or CH₃CO- group, so iodoform test is negative; ethanol (which has CH₃CH₂OH) DOES give iodoform
**Iodoform test (positive) requires CH₃-CHOH- or CH₃-CO-** in the substrate. Phenol has neither → **iodoform test is NEGATIVE for phenol**. **Ethanol (CH₃CH₂OH) has CH₃-CHOH-**, so it gives iodoform. So does acetone (CH₃-CO-CH₃), acetaldehyde, methyl ketones. Common NEET trap.
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