CBSE Class 11-science Answered
The shape of BrF5 molecule is square pyramidal.
The angle will be slightly less than 900.
According to the VSEPR theory, the shape of the molecule is determined by both the total number of electron pairs (bonding and non-bonding) around the molecules central atom and the orientation of these electron pairs in the space around the central atom.
In order to minimize the repulsion forces between them, electron pairs around the molecules central atom, tend to stay as far away from each other as possible.
Xe has electronic configuration 5s2 5p6.
In XeF2, there are two bonding pairs and three lone pair of electrons. So, according to the VSEPR theory the structure will be trigonal bypyramidal to avoid the electron pair repulsions.
In case of XeF4, the structure will be square planar. There are four pairs of bonding electrons and two lone pairs in the molecule. The two lone pairs will be opposite each other (to maintain symmetry), which makes for a square planar molecular geometry.
XeF6 has has pentagonal bipyramid geometry due to sp3d3 hybridization. One trans position is occupied by a lone pair giving a distorted octahedral shape.