(a)[2]
Label one bond angle on each of complexes P, Q, R and S, and state the angle size in degrees.
(b)[2]
State the shapes of complexes P, Q, R and S.
(c)[1]
Two L ligands are replaced by two \textbf{different} monodentate ligands X and Y in each of complexes P, Q, R and S. Identify all the complexes which form new complexes that show geometrical isomerism.
(d)[1]
Three L ligands are replaced by three \textbf{different} monodentate ligands X, Y and Z in each of complexes P, Q and R. Identify all the complexes which form new complexes that show optical isomerism.