Halides of sulfur Two important halides of sulfur are SF₄ and SF₆ .

(i) Sulfur tetrafluoride : SF₄ is formed by the reaction of sulfur with CoF₃ .

S + F CoF₃ ———> SF₄ + 4CoF₂

It is a color gas which is quite reactive. It is hydrolyzed with water.

SF₄ + 2H₂O ———> SO₂ + 4HF

It is used for fluorinating inorganic and organic compounds.

Structure: It has see-saw structure with sp³ d -hybridization and is derived from triogonal bipyramid geometry in which an equatorial position is occupied by a lone pair of electrons.

(ii) Sulfur hexafuoride: SF₆ is prepared by burning sulfur in a stream of fluorine. OF₆ is not known though sulfur forms SF₆. This is because oxygen has no d -orbitals in its valence shell.

SF₆ is a colorless gas. It is extremely inert substance even at red heat. It does not react with water. on account of its chemical inertness and dielectric strength, it is used as an insulator in high voltage generators and switch-gears.

Structure : It has an octahedral structure with Sp³d² -hybridization around the central sulfur atom.

Therefore, all S —F bond distances are equal in its structure.