How Do You Calculate Bond Order?

How Do You Calculate Bond Order?

How Do You Calculate Bond Order?

The bond order, which is the number of bonds between any two given atoms, is calculated using the formula: Bond order = (Bonding electrons - Anti-bonding electrons) / 2.The Lewis structures of atoms form the basis for calculating the bond order.

The bond order of a molecule that has multiple Lewis structures is calculated as the average of these Lewis structures. For example, sulfur dioxide has three bonds: a single bond for sulfur oxide in one Lewis structure and a double bond for sulfur oxide in a different Lewis structure within the molecule. This gives a bond order of 1.5, which is the average value of the three bonds.

In molecular orbital theory, bond orders are calculated by assuming that a pair of electrons in a bonding molecular orbital form one bond while a pair of electrons in a non-bonding molecular orbital nullify the effect of one bond.

For example, the bonding molecular orbital of the oxygen molecule has eight valence electrons while the anti-bonding molecular orbital of the same molecule has four valence electrons. So, the bond order of the oxygen molecule can be calculated as follows:

Bond order = (Bonding electrons - Anti-bonding electrons) / 2

  1. Bond order = (8 - 4) / 2
  2. Bond order = 4 / 2
  3. Bond order = 2