• For simple cases the T-metal oxidation state is equal to the
charge on the metal ion once all the ligands have been
removed.
T-Metal ox state = (complex - ligand) charges
eg.
[Co(NH3)4Cl2]Cl
Þ
+1 = Co + (4x0 + 2x-1)
re-arrange Þ Co = +1 - (4x0 + 2x-1) = +3
• Examples of complexes (or complex ions) with coordination
numbers 2, 4 & 6 are given in the next Table.