Chemistry - GOC Question with Solution | TestHub

All four conjugate bases are phenoxides; the methyl group is electron-donating and destabilises the negative charge, so all three cresols are weaker acids than phenol. The destabilisation is felt most at the ortho position (closest to O⁻) and least at the meta position (no resonance interaction with the methyl). Order : phenol $>$ m-cresol $>$ p-cresol $>$ o-cresol, i.e. a $>$ c $>$ d $>$ b. (pKa : 9.95, 10.09, 10.26, 10.29.)