Acidic character α stability of conjugate base (anion)

As stability of anion $\propto -\text{M}$ and $–\mathrm{I}$ effect . $-\mathrm{C}\mathrm{l}$ and $-\mathrm{F}$ have $(–\mathrm{I}>+\mathrm{M}\mathrm{e}\mathrm{f}\mathrm{f}\mathrm{e}\mathrm{c}\mathrm{t})$ in which $\mathrm{F}$ is more electron

withdrawing due to greater electronegativity. $\mathrm{N}{\mathrm{O}}_2$ and $\mathrm{C}\mathrm{N}$ have both $-\mathrm{I}$ and $-\mathrm{M}$ effect with $\mathrm{N}{\mathrm{O}}_2$ being more electron withdrawing.

Order of $-\mathrm{I}-$ effect $-\mathrm{N}{\mathrm{O}}_2>\mathrm{C}\mathrm{N}>-\mathrm{F}>-\mathrm{C}\mathrm{l}$ Hence, order of acidity ka will be

${\mathrm{O}}_2\mathrm{N}\mathrm{C}{\mathrm{H}}_2\mathrm{C}\mathrm{O}\mathrm{O}\mathrm{H}>\mathrm{N}\mathrm{C}\mathrm{ }\mathrm{C}{\mathrm{H}}_2\mathrm{C}\mathrm{O}\mathrm{O}\mathrm{H}>\mathrm{F}\mathrm{C}{\mathrm{H}}_2\mathrm{C}\mathrm{O}\mathrm{O}\mathrm{H}>\mathrm{C}\mathrm{l}\mathrm{ }\mathrm{C}{\mathrm{H}}_2\mathrm{C}\mathrm{O}\mathrm{O}\mathrm{H}$