Assertion (A): 4-Nitrophenol is more acidic than 3-nitrophenol. Reason (R): In 4-nitrophenoxide the negative charge on oxygen can be delocalised onto the nitro group by the -M effect, whereas in 3-nitrophenoxide only the -I effect of nitro operates.

ABoth A and R are true and R is the correct explanation of A
BBoth A and R are true but R is not the correct explanation of A
CA is true but R is false
DA is false but R is true

Answer: A

At the para position the nitro group is in conjugation with the phenoxide oxygen, so structures with the charge on the nitro oxygens are possible. At the meta position the nitro group cannot be conjugated with the oxygen in this way, and only its -I effect acts. So A is true and R explains it.

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Assertion (A): 4-Nitrophenol is more acidic than 3-nitrophenol. Reason (R): In 4-nitrophenoxide the negative charge on oxygen can be delocalised onto the nitro group by the -M effect, whereas in 3-nitrophenoxide only the -I effect of nitro operates.

Answer: A

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