The ratio of ${\mathrm{p}}_{\mathrm{\pi }}-{\mathrm{d}}_{\mathrm{\pi }}$ bonds is SO₂ and SO₃ molecules

To calculate the ratio of pπ−dπ bonds in SO₂ and SO₃ molecules, we need to consider the number of π bonds formed by the overlap of p orbitals on the sulfur and oxygen atoms (pπ bonds) and the number of π bonds formed by the overlap of d orbitals on the sulfur and oxygen atoms (dπ bonds).

In both SO₂ and SO₃, the sulfur atom does not have any d electrons available for bonding, so there are no dπ bonds in either molecule.

Therefore, the ratio of pπ−dπ bonds in SO₂ and SO₃ molecules is simply the ratio of the number of π bonds in each molecule. As we determined earlier, SO₂ has two π bonds, while SO₃ has three π bonds. Therefore, the ratio of pπ−dπ bonds in SO₂ to SO₃ is:

pπ−dπ bonds in SO₂ : pπ−dπ bonds in SO₃ = number of π bonds in SO₂ : number of π bonds in SO₃ = 2 : 3

So the ratio of pπ−dπ bonds in SO₂ to SO₃ is 2:3.