Question

A simplified application of MOT to the hypothetical molecule $OF$ would give its bond order as:

• A. 2
• B. 1.5
• C. 1
• D. 0.5

Answer 1

The correct option is B 1.5

The elctronic configuration of the hypothetical molecule would be:
$\left({\sigma }_{1S}{)}^2\right({\sigma }_{1S}^{\ast }{)}^2\left({\sigma }_{2S}{)}^2\right({\sigma }_{2S}^{\ast }{)}^2\left({\sigma }_{2p_z}{)}^2\right({\pi }_{2p_x}{)}^2\left({\pi }_{2p_y}{)}^2\right({\pi }_{2p_x}^{\ast }{)}^2({\pi }_{2p_y}^{\ast }{)}^1$

So bond order would be:
$\frac{1}{2}(\text{number of bonding electrons}-\text{number of antibonding electrons}$
$=\frac{1}{2}(10-7)=1.5$