There are 12F-S-F `90^(@)` BOND angle S in `SF_(6)` has an expanded OCTET With `H_(2)O, SF_(6)`on accept lonepair of electron in the empty 3d atomic orbital and gets hydrolysed `SF_(6)` has a distorted OCTAHEDRAL geometry
Solution :`SF_(6)=` octahedral structure because, So undergo `sp^(3)d^(2)` HYBRIDIZATION. It is HIGHLY inactive.