The increasing order of pKa values of the fol | vedclass

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(C) The acidity of phenols is determined by the stability of the phenoxide ion formed after the loss of a proton. Electron-withdrawing groups $(EWG)$

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$D < A < C < B$

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(C) The acidity of phenols is determined by the stability of the phenoxide ion formed after the loss of a proton. Electron-withdrawing groups $(EWG)$ increase acidity (decrease $pKa$),while electron-donating groups $(EDG)$ decrease acidity (increase $pKa$).$A$: Phenol (reference).$B$: $p$-nitrophenol ($-NO_2$ is a strong $EWG$,increases acidity).$C$: $m$-nitrophenol ($-NO_2$ is an $EWG$,increases acidity but less than $p$-isomer due to lack of resonance effect).$D$: $p$-methoxyphenol ($-OCH_3$ is an $EDG$,decreases acidity).Acidity order: $B > C > A > D$.Since $pKa = -\log(Ka)$,the increasing order of $pKa$ is the reverse of the acidity order: $D < A < C < B$.

The increasing order of $pKa$ values of the following compounds is:

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