1) Stability decreases with increase in atomic number of the elements.
2) For a given ligand , the complex containing the metal in higher oxidation state is the more stable one . E.g [Co(NH3)6]³+ is more stable than [Co(NH3)6]²+ .
- This is due to the fact that the higher the oxidation state, the metal cation is smaller and has higher charge density. It therefore attracts the ligand more strongly than the lower oxidation state metal cation.
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