Choose all correct statements about the compound shown. Take $p K_{a}$ of acetic acid as 4.8 and the first $p K_{a}$ of carbonic acid as 6.4.

AIt is a stronger acid than acetic acid.
BIt liberates carbon dioxide from aqueous sodium hydrogencarbonate.
CIt is obtained in good yield by treating phenol with dilute nitric acid at 298 K.
DIts anion is less stabilised than the phenoxide ion.

Answer: A, B

The compound is 2,4,6-trinitrophenol (picric acid) with

p K_{a}

near 0.4, so it is stronger than acetic acid and than carbonic acid (A, B). Dilute nitric acid gives only mononitrophenols, and picric acid needs concentrated nitric acid or sulphonation first (C wrong). Three nitro groups stabilise the anion strongly, so D is wrong.

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Choose all correct statements about the compound shown. Take pKa​ of acetic acid as 4.8 and the first pKa​ of carbonic acid as 6.4.

Answer: A, B

More questions on Acidity and reactions of drawn phenols

Choose all correct statements about the compound shown. Take $p K_{a}$ of acetic acid as 4.8 and the first $p K_{a}$ of carbonic acid as 6.4.