Isostructural compounds are those compounds which have same structure as well as same hybridisation. Formula for find hybridisation : H=(lp+σ+ coordinate bond ) Ip= Lone pair bp= Bond pair σ= Sigma bond
S. No.
Molecule
H (Steric number)
Hybridisation
B.P.
L.P.
Shape
(A)
SO42−
4
sp3
4
0
CrO42−
4
sp3
4
0
(B)
SiCl4
4
sp3
4
0
TiCl4
4
sp3
4
0
(C)
NH3
4
sp3
3
1
NO3−
4
sp2
3
0
(D)
BCl3
3
sp2
3
0
BrCl3
5
sp3d
3
2
If number of sigma bond (σ), co-ordinate bond and lone pair are same for given pairs, they are isostructural. Hence, SO42−,CrO42−,SiCl4 and TiCl3 have tetrahedral shape and are isostructural.