Question

Consider the nitrogen molecule and the N2+ molecular ion:

(a) Give the bond order of each species. If a fraction is needed, use a decimal number. Bond order N2 = Bond order N2+ =

(b) Predict which species should be paramagnetic. Is N2 paramagnetic? Is N2+ paramagnetic?

(c) Predict which species has the greater bond dissociation energy. The species with the largest bond dissociation energy is: a. N2 b. N2+

Answer 1

a)For N2 we have

Total number of electrons:14
Electronic Configuration=:σ1s² σ*1s² σ2s² σ*2s² π 2py² [π2pz² σ2px2 ]

No of bonding electrons =10

No of antibonding electrons =4

Bond Order=10-4/2=6/2=3

For N2+ we have

Bond Order of N2⁺:
Total number of electrons:13
Electronic Configuration=:σ1s² σ*1s² σ2s² σ*2s² π 2py² [π2pz² σ2px1 ]

No of bonding electrons =9

No of antibonding electrons =4

Bond Order=[9-4]/2=5/2=2.5

b) N2 has no unpaired elctron so it s dimagnetic and N2+ has 1 unpaired electron so is paramagnetic.

c)Bond dissociation energy is proportional to bond order so N2 has higher bond order so its Bond dissociation energy will also be higher.