$\mathrm{O}-\mathrm{O}$ bond length in $\mathrm{H}_{2} \mathrm{O}_{2}$ is $\underline{\mathrm{X}}$ than the $\mathrm{O}-\mathrm{O}$ bond length in $\mathrm{F}_{2} \mathrm{O}_{2}$. The $\mathrm{O}-\mathrm{H}$ bond length in $\mathrm{H}_{2} \mathrm{O}_{2}$ is $\underline{Y}$ than that of the $\mathrm{O}-\mathrm{F}$ bond in $\mathrm{F}_{2} \mathrm{O}_{2}$. Choose the correct option for $\underline{\mathrm{X}}$ and $\underline{Y}$ from the given below.

JEE Main · 2023 · 01 Feb 2023 · Shift 2 · Chemical Bonding and Molecular Structure

O - O

bond length in

H_{2} O_{2}

\underline{X}

than the

O - O

bond length in

F_{2} O_{2}

. The

O - H

bond length in

H_{2} O_{2}

\underline{Y}

than that of the

O - F

bond in

F_{2} O_{2}

.
Choose the correct option for

\underline{X}

and

\underline{Y}

from the given below.

Answer: (D)

In difluorine dioxide the strongly electron-withdrawing fluorine atoms draw charge into the

O - O

region and give that bond appreciable double-bond character, shortening it to about

122

pm, whereas in hydrogen peroxide the

O - O

bond is a normal single bond near

148

pm; the

O - O

bond in hydrogen peroxide is therefore the longer one. Comparing the terminal bonds, the

O - H

bond of hydrogen peroxide is much shorter than the

O - F

bond of difluorine dioxide because hydrogen is far smaller than fluorine. Hence the

O - O

bond is longer and the

O - H

bond is shorter.

JEE Main · 2023 · 01 Feb 2023 · Shift 2 · Single correct option