Complex ion A has one $\text{Fe}^{3+}$ ion and six $\text{CN}^-$ ligands, while complex ion B has one $\text{Fe}^{2+}$ ion and six $\text{CN}^-$ ligands. State the formulae of these two complex ions, including the overall charge on each one. complex ion A …………………… complex ion B ……………………
Explain why a solution containing complex ion A and a solution containing complex ion B show different colours.
In complex ion A, the carbon atom of each $\text{CN}^-$ ligand bonds to the $\text{Fe}^{3+}$ ion. State the type of bond involved.
The complex ions do not all have the same geometry. Complex ion A is octahedral. $\text{Ag}^+$ ions form a linear complex with ammonia. Ni atoms form a tetrahedral complex with carbon monoxide molecules. The carbon atom in the monodentate carbon monoxide ligand bonds to the nickel atom. $\text{Pd}^{2+}$ ions form a square planar complex with chloride ions. Complete Fig. 6.1 so that the geometry of each of these four ions is shown, using three-dimensional bonds where needed. Mark one bond angle on each complex ion.