What is meant by the term bond order? Calculate the bond order of: N2, O2, and
Bond order is defined as one half of the difference between the number of electrons present in the bonding and anti-bonding orbitals of a molecule.
If Na is equal to the number of electrons in an anti-bonding orbital, then Nb is equal to the number of electrons in a bonding orbital.
Bond Order:
If Nb > Na, then the molecule is said be stable. However, if Nb≤ Na, then the molecule is considered to be unstable.
Bond order of N2 :
Number of bonding electrons, Nb = 10
Number of anti-bonding electrons, Na = 4
Bond order of nitrogen molecule= 1/2 (10-4)=3
Bond order of O2:
Number of bonding electrons, Nb = 8
Number of anti-bonding electrons, Na = 4.
Bond order of Oxygen molecule = 1/2 (8-4)=2
Bond order of O2+ :
Number of bonding electrons, Nb = 8
Number of anti-bonding electrons, Na = 3
Bond order of O2- = 1/2 (8-3) = 2.5
Bond order of O2-:
Number of bonding electrons, Nb = 8
Number of anti-bonding electrons, Na = 5
Bond order of O2- = 1/2 (8-5) = 1.5