Question 49

Given below are two statements :

Statement (I) : p-nitrophenol is more acidic than m-nitrophenol and o-nitrophenol. 

Statement (II) : Ethanol will give immediate turbidity with Lucas reagent. 

In the light of the above statements, choose the correct answer from the options given below :

Statement I: p-Nitrophenol is more acidic than m-nitrophenol and o-nitrophenol.

The $$-NO_2$$ group is electron-withdrawing. At the para position, it stabilizes the phenoxide ion through resonance (direct conjugation), making p-nitrophenol the most acidic among the three isomers. This is true.

(Note: While o-nitrophenol has intramolecular hydrogen bonding which reduces its effective acidity in solution, p-nitrophenol has the strongest -R effect stabilization.)

Statement II: Ethanol will give immediate turbidity with Lucas reagent.

Lucas reagent (conc. HCl + ZnCl$$_2$$) is used to distinguish between primary, secondary, and tertiary alcohols. Primary alcohols like ethanol do not give immediate turbidity - they show no reaction at room temperature. Only tertiary alcohols give immediate turbidity. This is false.

Statement I is true but Statement II is false. The answer corresponds to Option (1).

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