Question

Using MOT write the electronic configuration, bond order and magnetic property of

oxygen molecule (O2)?​

Answer 1

Explanation:

Oxygen molecule O

2

: The electronic configuration of oxygen (z=8) in the ground state is 1s

2

2s

2

2p

4

. Each oxygen atom has 8 electrons, hence in O

2

molecule there are 16 electrons.

Therefore, the electronic configuration of O

2

is as follows :

O

2

:KK(σ

2s

)

2

(σ

2s

∙

)

2

(π

2p

x

)

2

=(π

2p

y

)

2

(π

2p

x

)

1

=(π

2p

y

∙

)

1

The molecular orbital energy level diagram of oxygen molecule is given as follows :

Bond order

2

N

b

−N

a

=

2

8−4

=2

Thus, oxygen molecule has two bonds. i.e., one is bond and one p bond. The last two electrons in p

2px

∙

and p

2py

∙

orbitals will remain unpaired. Therefore, oxygen molecule has paramagnetic character due to the presence of two unpaired electrons.