Question

Write all the geometrical isomers of [Pt(NH₃)(Br)(Cl)(py)] and how many of these will exhibit optical isomers?

Answer 1

\[\begin{array}{cc} \ce{NH3}\phantom{.....}\ce{Br}\\ \phantom{.}\backslash\phantom{...}/\\ \ce{Pt}\\ /\phantom{...}\backslash\\ \ce{Cl}\phantom{.....}\ce{Py}\phantom{.} \end{array}\]

\[\begin{array}{cc} \ce{H3N}\phantom{.....}\ce{Br}\phantom{.}\\ \phantom{.}\backslash\phantom{...}/\\ \ce{Pt}\\ /\phantom{...}\backslash\\ \ce{Py}\phantom{.....}\ce{Cl}\ \end{array}\]

\[\begin{array}{cc} \ce{H3N}\phantom{.....}\ce{Cl}\phantom{.}\\ \phantom{.}\backslash\phantom{...}/\\ \ce{Pt}\\ /\phantom{...}\backslash\\ \ce{Py}\phantom{.....}\ce{Br}\ \end{array}\]

Square planar complexes never show optical isomerism because of the plane of symmetry present in this case.