Comment on the nature of two S–O bonds formed in SO2 molecule. Are the two S–O bonds in this molecule equal?


The electronic configuration of S is 1s2 2s2 2p6 3s2 3p4.


One electron from 3p orbital goes to the 3d orbital and S undergoes sp2 hybridization, during the formation of SO2 molecule. Two of these orbitals form sigma bonds with two oxygen atoms and the third contains a lone pair of electrons. The p-orbital and d-orbital contain an unpaired electron each. An electron in the p-orbital forms p π- p π bond with one oxygen atom and the other electron forms p π- d π bond with the other oxygen. This is the reason SO2 has a bent structure. Also, it is a resonance hybrid of structures I and II, with equal bond lengths of 143pm.



21
1