Question

What are the main defects of Werner’s theory?

Answer 1

1. Werner’s theory does not explain how ligands bond to the central metal ion. It lacks the concept of coordinate covalent bonds or orbital interactions.
2. It fails to explain the magnetic properties of coordination compounds. The theory does not clarify why some complexes are paramagnetic (contain unpaired electrons) while others are diamagnetic (contain only paired electrons).
3. Werner’s theory cannot account for the color of coordination compounds. It does not explain why many complexes are coloured or why the same metal shows different colours with different ligands.
4. The theory ignores the electronic configuration of the central metal ion, which is important in determining the structure and reactivity of the complex.
5. It does not predict the geometry of coordination compounds based on orbital theory. While it introduces the concept of coordination number, it does not explain why certain geometries, such as octahedral or tetrahedral, are formed.
6. Werner’s theory gives an incomplete explanation of isomerism. Although it predicts the existence of geometrical isomers, it does not explain their structural basis or different types.