What is the Difference Between Coordination Number and Oxidation Number?

The difference between coordination number and oxidation number lies in their definitions and the concepts they represent in coordination chemistry:

Coordination Number: This is the number of ligand atoms that are directly bonded to the central metal atom in a coordination compound. The coordination number can be related to the molecular geometry of the coordination compound. For example, in Co(NH3)6, the coordination number is 6 because there are six ligands (NH3) attached to the central atom Co.
Oxidation Number: This is the charge of the central atom in a coordination compound if we remove all the ligands and electrons shared between the ligands and the central atom. To determine the oxidation number, you can start by figuring out the charges of the non-metal (non-transition) ions and then assign a charge to the central atom to make the overall molecule neutral in charge. For example, in the coordination complex [Fe(CN)6]3-, the oxidation number of iron (Fe) is +3.

In summary, the coordination number refers to the number of ligands attached to the central metal atom, while the oxidation number represents the charge of the central atom if all ligands and shared electrons are removed.

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What is the Difference Between Coordination Number and Oxidation Number?

Comparative Table: Coordination Number vs Oxidation Number

Here is a table comparing the coordination number and oxidation number:

Property	Coordination Number	Oxidation Number
Definition	The coordination number is the number of ligands attached to the metal center in a coordination complex.	The oxidation number is the charge of the central atom if all the ligands and electron pairs are removed.
Terminology	Ligands are atoms, ions, or molecules that donate electron pairs to the central metal atom.	The oxidation state is determined based on the charges of each ligand and the overall charge of the coordination compound.
Range	Coordination numbers are usually between 2 and 9, but higher values are possible.	Oxidation numbers can range from -1 to +8, depending on the electronegativity of the ligands and the overall charge of the coordination compound.
Relationship	The coordination number is related to the molecular geometry of the coordination compound.	The oxidation number helps determine the molecular geometry and the nature of the bonds between the ligands and the central atom.

In summary, the coordination number refers to the number of ligands attached to the central atom in a coordination compound, while the oxidation number represents the charge of the central atom if all the ligands and electron pairs are removed. Both properties are essential for understanding the structure and reactivity of coordination compounds.

Guilherme Mazui

Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.