The correct order of pK_{a} values for the fo | vedclass

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(B) 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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$b > d > a > c$

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(B) 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,while electron-donating groups $(-EDG)$ decrease acidity.$1$. Compound $(c)$ has a $-NO_{2}$ group,which exerts a strong $-M$ and $-I$ effect,making it the most acidic.$2$. Compound $(a)$ is phenol,which has no substituent.$3$. Compound $(d)$ has an isopropyl group,which exerts a $+I$ effect and hyperconjugation,making it less acidic than phenol.$4$. Compound $(b)$ has a $-N(CH_{3})_{2}$ group,which exerts a strong $+M$ effect,making it the least acidic.Therefore,the order of acidic strength is $(c) > (a) > (d) > (b)$.Since $pK_{a} \propto \frac{1}{	ext{acidic strength}}$,the order of $pK_{a}$ values is $(b) > (d) > (a) > (c)$.

The correct order of $pK_{a}$ values for the following compounds is:
$(a)$ Phenol
$(b)$ $p$-Dimethylaminophenol
$(c)$ $p$-Nitrophenol
$(d)$ $p$-Isopropylphenol

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The correct order of $pK_{a}$ values for the following compounds is:$(a)$ Phenol$(b)$ $p$-Dimethylaminophenol$(c)$ $p$-Nitrophenol$(d)$ $p$-Isopropylphenol