The correct order of acid strength of the following compounds A. Phenol B. \(p\)-Cresol C. \(m\)-Nitrophenol…
The correct order of acid strength of the following compounds
A. Phenol
B. \(p\)-Cresol
C. \(m\)-Nitrophenol
D. \(p\) - Nitrophenol is
\(\mathrm{C}>\mathrm{B}>\mathrm{A}>\mathrm{D}\)
\(\mathrm{D}>\mathrm{C}>\mathrm{A}>\mathrm{B}\)
\(\mathrm{B}>\mathrm{D}>\mathrm{A}>\mathrm{C}\)
\(\mathrm{A}>\mathrm{B}>\mathrm{D}>\mathrm{C}\)
Solution
Electron withdrawing \(-\mathrm{NO}_{2}\) substituent has an acid-strengthening effect while the electron releasing \(-\mathrm{CH}_{3}\) substituent has an acid-weakening effect on phenol. Thus, \(p\)-cresol is the weakest acid amongst the given compounds. The \(m\) - and \(p\)-nitrophenols are stronger acid than phenol \((p\)-isomer is more strong than \(m\)-isomers). The given choice (b) satisfies this requirement.
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