Question

Many structures of phosphorus- and sulfur-containing compounds are drawn with some $\mathrm{P}=O$and $\mathrm{P}=S$bonds. These bonds are not the typicalbonds we've considered, which involve the overlap of twoorbitals. They result instead from the overlap of a $d$orbital on the phosphorus or sulfur atom with a $p$orbital on oxygen. This type of $\pi$bonding is sometimes used as an explanation for why${\text{H}}_{\text{3}}{\text{PO}}_{\text{3}}$has the first structure below rather than the second:

Draw a picture showing how a$d$orbital and a$p$orbital overlap to form abond.

Short answer

The required picture showing how a $d$orbital and a $p$orbital overlap to form a $\pi$bond is:

Step-by-step solution

Definition of Hybridisation

Hybridization is the process of combination of two or more orbitals such as to to result in the orbitals of same shape, size and energy.

Configuration of phosphorus

The phosphor atom is a member of the Group 5A with the valence shell configuration of ${\text{3s}}^{\text{2}}{\text{3p}}^{\text{3}}$.

Phosphorous acid is a chemical substance with the formula ${\text{H}}_{\text{3}}{\text{PO}}_{\text{3}}$. This acid is diprotic, not triprotic, as the formula might suggest.

${\text{HP(O)(OH)}}_{\text{2}}$is tetrahedral in the solid state, with one shorter $\text{P = O}$bond and two longer $\text{PO(H)}$bonds. This species has an exceedingly small tautomer ${\text{P(OH)}}_{\text{3}}$in equilibrium with it. In the diagram below, both structures are depicted.

Hybridisation of H3PO3

Because $\mathrm{P}$and O create a $d-p\pi$bond, the first structure in the diagram above is a reasonable illustration of phosphorous acid.

${\text{H}}_{\text{3}}{\text{PO}}_{\text{3}}$is ${\mathrm{Sp}}^3$a hybridised, sigma bonds will be formed using $\text{1 s}$and $\text{3 p}$orbitals. However, because there is still one $\pi$bond between P and O, the d phosphorus orbital will be used for sidewise overlapping with a P oxygen orbital.