Question

SF6 is known but SH6 is not. Compound of O with fluorine is known as fuorides not oxides. Explain.

Answer 1

Hybridization of SF₆ is sp³d² ,
For formation of SH₆ the hybridization will be the same.
d orbitals are of very high energy and sp³d² hybridization is possible only with highly electronegative elements only like F.
Electronegativity value of H is not sufficient to bring the energy of d orbitals equal to the energy of p orbitals which is required for formation of sp³d² hybrid molecular orbitals.

Out of fluorine and oxygen, fluorine is more electronegative than oxygen. Therefore, electron density is nearer to fluorine and compounds of oxygen with fluorine are known as fluorides of oxygen not oxides of fluorine. Like oxygen difluoride OF₂.