Question

In $H_2{O}_2$ molecule the $O-O$ bond length is:
A) $1.34A$
B) $1.48A$
C) $1.54A$
D) $1.20A$

Answer 1

Hint: The average distance between the nuclei of two bound atoms in a molecule is known as bond length or bond distance in molecular geometry. It's a property of a bond between fixed-type atoms that can be transferred, despite the rest of the molecule being largely unaffected.

Complete answer: The distance between the centres of two covalently bonded atoms is known as bond length. The number of bound electrons determines the length of the bond (the bond order). The greater the pull between the two atoms and the shorter the bond length, the higher the bond order. In general, the length of a bond between two atoms is approximately equal to the number of their covalent radii.
Bond length is proportional to bond order: the longer the bond, the more electrons involved in its creation. Bond length is also inversely related to bond strength and bond dissociation energy: a stronger bond would be shorter if all other variables remain constant. Half of the bond width is equal to the covalent radius in a bond between two similar atoms.
The most basic form of peroxide is hydrogen peroxide (oxygen-oxygen single bond). It's a colourless liquid that's used in aqueous solutions to keep things safe. It is used as a disinfectant as well as a bleaching agent. In rocketry, concentrated hydrogen peroxide is used as a propellant because it is a highly reactive oxygen species. $H_2{O}_2$ is the molecular formula for hydrogen peroxide.
Hydrogen peroxide has a non-planar form. With $O-O$ spins, $H_2{O}_2$ has an open book structure. ${111}^{\circ }$ is the dihedral angle. The length of the $O-O$ bond is $145.8$ pm, and the length of the $O-H$ bond is $9.88$ pm ($9.88\times {10}^{-13}$). Owing to repulsion between the lone pairs of oxygen atoms, the bond length is significantly longer than a single bond.
The correct option is B.

Note:
With their lone pair electrons repelling each other, the two oxygen atoms are now trapped in close proximity. They may as well form as many bonds as they can while they're together. Hydrogen peroxide is highly unstable because of this.