According to molecular orbital theory, which of the following molecules has a bond order of 1.5?

• A. N2
• B. NO
• C. CO
• D. O2

Answer: (B)

Verified step by step guidance

1. Recall that bond order in molecular orbital theory is calculated using the formula: \(\text{Bond Order} = \frac{(\text{number of bonding electrons}) - (\text{number of antibonding electrons})}{2}\).
2. Determine the total number of valence electrons for each molecule: N\(_2\), NO, CO, and O\(_2\).
3. Write the molecular orbital electron configuration for each molecule, filling the bonding and antibonding orbitals according to the molecular orbital diagram appropriate for diatomic molecules involving second-period elements.
4. Count the number of electrons in bonding and antibonding orbitals for each molecule and apply the bond order formula to find the bond order for each.
5. Identify which molecule has a bond order of 1.5 by comparing the calculated bond orders.