Western Connecticut State University
General Chemistry I CHE 110
Molecular Orbital Theory
These problems are for practice in drawing your molecular orbital diagrams, molecular electron
configurations and determining bond order.
The following questions pertain to the F2 molecule:
A)
Draw the molecular orbital energy diagram for this molecule. Label all of the
orbitals specifically.
σ*2px
π*2py π*2pz
2p
2p
π2py π2pz
Energy
σ2px
2s
σ*2s
2s
σ2s
1s
F
σ*1s
σ1s
1s22s22p5
B)
1s
F
1s22s22p5
Give the molecular electron configuration for the molecule:
(σ1s) 2 (σ1s*) 2 (σ2s) 2 (σ2s*) 2 (σ2px) 2 (π2p) 4 (π2p*) 4
C)
Determine the bond order for the molecule:
Bond Order = (10 – 8) / 2 = 1
D)
Indicate whether the species is paramagnetic or diamagnetic:
Diamagnetic: No unpaired electrons
F)
Compare the relative stability of this molecule to F2+ and F2-:
F2+ > F2 > F2- (Based on their Bond Orders)
Western Connecticut State University
General Chemistry I CHE 110
Molecular Orbital Theory
The following questions pertain to the C2+ ion:
A)
Draw the molecular orbital energy diagram for this ion. Label all of the
orbitals specifically.
σ*2px
π*2py π*2pz
2p
2p
σ2px
π2py π2pz
Energy
2s
σ*2s
2s
σ2s
1s
C
σ*1s
σ1s
1s22s22p2
B)
1s
C+
1s22s22p1
Give the molecular electron configuration for the ion:
(σ1s) 2 (σ1s*) 2 (σ2s) 2 (σ2s*) 2 (π2p) 3
C)
Determine the bond order for the ion:
Bond Order = (7 – 4) / 2 = 1.5
D)
Indicate whether the species is paramagnetic or diamagnetic:
Paramagnetic: one unpaired electron
F)
Compare the relative stability of this molecule to C2 and C2-:
C2- > C2 > C2+ (Based on their Bond Orders)
Western Connecticut State University
General Chemistry I CHE 110
Molecular Orbital Theory
The following questions pertain to the NO molecule:
A)
Draw the molecular orbital energy diagram for this molecule. Label all of the
orbitals specifically.
σ*2px
π*2py π*2pz
2p
2p
π2py π2pz
Energy
σ2px
2s
σ*2s
2s
σ2s
1s
N
2
2
σ*1s
O
σ1s
3
1s 2s 2p
B)
1s
2
1s 2s22p4
Give the molecular electron configuration for the molecule:
(σ1s) 2 (σ1s*) 2 (σ2s) 2 (σ2s*) 2 (σ2px) 2 (π2p) 4 (π2p*) 1
C)
Determine the bond order for the molecule:
Bond Order = (10 – 5) / 2 = 2.5
D)
Indicate whether the species is paramagnetic or diamagnetic:
Paramagnetic: One unpaired electron
F)
Compare the relative stability of this molecule to NO+ and NO--:
NO+ > NO > NO- (Based on their Bond Orders)