Question

What would be the hybridization of the Oxygen in ${H_2}{O_2}$?
(A) $s{p^3}d$
(B) $sp$
(C) $s{p^2}$
(D) $s{p^3}$

Answer 1

As we know that oxygen atom contains two lone pairs and two bond pairs and there are no pi-bond interactions between oxygen atoms and according to the VSEPR there is repulsion between the valence electron pairs.

Complete solution:
The Valence shell electron pair repulsion theory (VSEPR) is based on the idea that in all atoms there is a repulsion between the valence electron pairs and thus the atoms will appear to organize themselves in a way that minimizes this repulsion of the pair of electrons. The geometry of the resulting molecule indicates this arrangement of atoms.
(a) For option A $s{p^3}d$
We know the $s{p^3}d$ hybridization is formed when one s-orbital combines with three p and one d-orbitals. Oxygen atom in hydrogen peroxide has two lone pairs and two bond pair electrons and does not have d-orbital to perform $s{p^3}d$. Hence the given option is wrong.
(b) For option B $sp$
We know the $sp$ hybridization is formed when one s-orbital combines with one p-orbital. Oxygen atoms in hydrogen peroxide have two lone pairs and two bond pair electrons and need $2p$ orbitals to perform hybridization. Hence the given option is wrong.
(c) For option C $s{p^2}$
We know the $s{p^2}$ hybridization is formed when one s-orbital combines with two p-orbitals. An Oxygen atom in hydrogen peroxide has two lone pair and two bond pair electrons and needs $2p$ orbitals to perform hybridization. Hence the given option is wrong.
(d) For option D $s{p^3}$
We know the $s{p^3}$ hybridization is formed when one s-orbital combines with three p-orbitals. Oxygen atoms in hydrogen peroxide have two lone pairs and two bond pair electrons and needed $2p$orbitals to perform hybridization. Hence the given option is right.
Therefore the correct answer is (D).

Note: Always remember that the oxygen atom in hydrogen peroxide is $s{p^3}$ hybridized because it contains two lone and two bond pairs of electrons possessing a total of eight electrons shared by the hydrogen atoms and this hybridization is the result of mixing of a $2s$ and three $2p$ orbitals.