NEET2002ChemistryGeneral Organic ChemistryActual
Assertion : Phenol is a weaker acid than ethanol. Reason : Groups with +M effect and -I effect decrease acidity at m -position.
Options
- AIf both the assertion and reason are true and reason is a correct explanation of the assertion.
- BIf both assertion and reason are true but assertion is not a correct explanation of the assertion.
- CIf the assertion is true but the reason is false.
- DIf both assertion and reason are false.
Correct answer
D. If both assertion and reason are false.
Step-by-step solution
Phenol is a stronger acid than the ethanol. This is due to the resonance stabilisaton of the phenolate ion which is produced after deprotonation. But there is no such stabilisation in the case of ethanol C ₂ H ₅ OH C ₂ H ₅ O ⁻+ H ⁺ The groups with +M and -I effect decrease the acidity at p -position, but at m -position the acidity is increased due to -I -effect.