Chemistry - GOC Question with Solution | TestHub

Conjugate bases : (a) ethoxide, localised on O ($\mathrm{p}{K}_{\mathrm{a}}$ ≈ 16); (b) $\mathrm{Cl}{\mathrm{O}}^{-}$, charge on O stabilised inductively by the electronegative chlorine ($\mathrm{p}{K}_{\mathrm{a}}$ of HOCl ≈ 7.5); (c) acetate, resonance-stabilised over two oxygens ($\mathrm{p}{K}_{\mathrm{a}}$ ≈ 4.8); (d) propanal enolate, resonance-stabilised but with much of the charge on carbon ($\mathrm{p}{K}_{\mathrm{a}}$ ≈ 17). So acetic acid $>$ HOCl $>$ ethanol $>$ propanal α-H, i.e. c $>$ b $>$ a $>$ d.