Write all the geometrical isomers of $[Pt(NH_3)(Br)(Cl)(Py)]$ and determine how many of these will exhibit optical isomerism.

(N/A) The complex $[Pt(NH_3)(Br)(Cl)(Py)]$ is a square planar complex of the type $[M(abcd)]$.
For a square planar complex of the type $[M(abcd)]$,there are $3$ possible geometrical isomers.
These isomers are formed by fixing one ligand (e.g.,$NH_3$) and varying the positions of the other three ligands $(Br, Cl, Py)$ relative to it.
$1$. $NH_3$ trans to $Br$ (with $Cl$ trans to $Py$).
$2$. $NH_3$ trans to $Cl$ (with $Br$ trans to $Py$).
$3$. $NH_3$ trans to $Py$ (with $Br$ trans to $Cl$).
Square planar complexes do not exhibit optical isomerism because they are planar and possess a plane of symmetry (the molecular plane itself). Therefore,none of these isomers will exhibit optical isomerism.