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Calculation of Oxidation Number

Consider the calculation of the chlorine oxidation number in HClO4. Chlorine has an oxidation number of +VII in this molecule. Know more about the same here.

In chemistry, it is important to be able to calculate the oxidation number of atoms in a molecule. This number can help you to understand how the atoms are bonded together and what type of chemical reaction has taken place. In some cases, it can be difficult to determine the oxidation number of an atom that occurs more than once in a molecule. In this brief note, we will discuss how to calculate the oxidation number of atoms that have identical bonding.

Oxidation Number of Atoms Occurring more than Once in a Molecule

It is important to note that the oxidation number of atoms occurring more than once in a molecule and having identical bonding can be calculated by taking the average of all the oxidation numbers of that atom in the molecule. For example, consider the calculation of the oxidation number of chlorine in HClO₄. In this molecule, chlorine has an oxidation number of +VII. However, since there are two chlorine with identical bonding, we must take the average of their oxidation numbers. Therefore, the overall oxidation number for chlorine in HClO₄ is +VI½.

Similarly, when calculating the oxidation number of carbon in CH₃CHO, we must take into account that there are two carbons with identical bonding. Therefore, the overall oxidation number for carbon in CH₃CHO is +II½.

It is important to keep in mind that this method of calculation is only applicable when all atoms in the molecule have identical bonding. If there are atoms with different types of bonding, then a more sophisticated method of calculation must be used. Nevertheless, this technique can be useful in many situations and can help to quickly determine the oxidation number of atoms in a molecule.

How to calculate

The oxidation number of atoms occurring more than once in a molecule and having identical bonding can be calculated by taking the average of all the oxidation numbers of that atom in the molecule. For example, to calculate the oxidation number of chlorine in HClO₄, we would take the average of +VII and +VII, which would give us an overall oxidation number of +VII. Similarly, to calculate the oxidation number of carbon in CH₃CHO, we would take the average of +I and +I, which would give us an overall oxidation number of+I.

It is important to keep in mind that this method of calculation is only applicable when all atoms in the molecule have identical bonding. If there are atoms with different types of bonding, then a more sophisticated method of calculation must be used. Nevertheless, this technique can be useful in many situations and can help to quickly determine the oxidation number of atoms in a molecule.

Example

Calculate the oxidation number of chlorine in HClO₄.

Since there are two chlorine with identical bonding, we must take the average of their oxidation numbers. Therefore, the overall oxidation number for chlorine in HClO₄ is +VI½.

Example

Calculate the oxidation number of carbon in CH₃CHO. 

Since there are two carbons with identical bonding, we must take the average of their oxidation numbers. Therefore, the overall oxidation number for carbon in CH₃CHO is +II½.

Example

Calculate the oxidation number of oxygen in H₃PO₄. 

Since there are four oxygens with identical bonding, we must take the average of their oxidation numbers. Therefore, the overall oxidation number for oxygen in H₃PO₄ is -II.

Conclusion

In Conclusion, the oxidation number of atoms that have identical bonding can be calculated by taking the average of all the oxidation numbers of that atom in the molecule. This method is only applicable when all atoms in the molecule have identical bonding. If there are atoms with different types of bonding, then a more sophisticated method of calculation must be used. Nevertheless, this technique can be useful in many situations and can help to quickly determine the oxidation number of atoms in a molecule. I hope this article helped you understand how to calculate the oxidation number of atoms that have identical bonding. If you have any questions, please feel free to leave a comment below. Thanks for reading!

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How do you calculate the oxidation number of an atom that occurs more than once in a molecule and has identical bonding?

Ans. The oxidation number of an atom is the charge that would exist on the atom if the bonds between atoms we...Read full

What is the oxidation number of an atom that has no bonds?

Ans. The oxidation number of an atom that has no bonds is 0.

What is the oxidation number of oxygen in H₂O₂; chlorine in Cl₂ and sulphur in H₂S?

Ans. The oxidation number of oxygen in H₂O₂ is -1; The oxidation number of chlorine in Cl₂ is 0; The ox...Read full

What is the oxidation number of hydrogen in H₂ and NH₃?

Ans. The oxidation number of hydrogen in H₂ is +0; The oxidation number of hydrogen in NH₃ is +0....Read full

How do you calculate the oxidation number of an atom that has multiple bonds?

Ans. The oxidation number of an atom in a molecule can be calculated by subtracting the sum of the electroneg...Read full