Answer:
a) octahedral electron domain geometry
b)square planar molecular geometry
c) a bond angle of 90°
Step-by-step explanation:
According to the Valence Shell Electron Pair repulsion Theory, the shape of a molecule is dependent on the number of electron pairs on the valence shell of the central atom in the molecule. These electron pairs orient themselves as far apart in space as possible to minimize electron pair repulsion.
Electron pairs may be lone pairs or bond pairs. Lone pairs of electrons cause more repulsion than bond pairs. These lone pairs often cause the molecular geometry to depart from what is predicted on the basis of the electron domain geometry due to greater repulsion of lone pairs.
When a molecule has six electron domains consisting of four bond pairs and two lone pairs, the bonding pairs arrange themselves at the corners of a square at a bond angle of 90° with the lone pairs found above and below the plane of the bonding groups leading to a square planar molecular geometry