Calculate the bond order, the molecular configuration, Number of bonding electrons and Number of anti-bondig electrons for the following molecules.

1. Carbon monoxide?

2.Nitrosonium ?

1 answer

To analyze carbon monoxide (CO) and nitrosonium ion (NO⁺), we can determine their molecular configurations, bond order, number of bonding electrons, and number of anti-bonding electrons using molecular orbital theory.

1. Carbon Monoxide (CO)

Molecular Configuration: The molecular orbital configuration for \( CO \) can be derived from its atomic orbitals:

  • Carbon (C) has the electronic configuration: \( 1s^2 2s^2 2p^2 \)
  • Oxygen (O) has the electronic configuration: \( 1s^2 2s^2 2p^4 \)

Combining the atomic orbitals, we get the following filling in of molecular orbitals:

  • \( \sigma_{1s}^2 \sigma_{1s}^2 \)
  • \( \sigma_{2s}^2 \sigma_{2s}^2 \)
  • \( \sigma_{2p_z}^2 \)
  • \( \pi_{2p_x}^2 \pi_{2p_y}^2 \) (both occupying the π orbitals)
  • \( \pi_{2p_x}^0 \pi_{2p_y}^0 \)

Thus, the configuration of CO is: \[ ( \sigma_{1s}^2) ( \sigma_{1s}^2) ( \sigma_{2s}^2) ( \sigma_{2s}^2) ( \sigma_{2p_z}^2) ( \pi_{2p_x}^2) ( \pi_{2p_y}^2) \]

Bond Order Calculation: Bond Order = \( \frac{(Number , of , bonding , electrons - Number , of , anti-bonding , electrons)}{2} \)

  • Bonding Electrons = 10 (2 from \( \sigma_{1s} \), 2 from \( \sigma_{2s} \), 2 from \( \sigma_{2p_z} \), 4 from \( \pi_{2p} \)).
  • Anti-bonding Electrons = 0.

Bond Order = \( \frac{10 - 0}{2} = 5\)

Number of Bonding and Anti-bonding Electrons:

  • Number of bonding electrons = 10
  • Number of anti-bonding electrons = 0

2. Nitrosonium Ion (NO⁺)

Molecular Configuration: The molecular orbital configuration for \( NO^+ \):

  • Nitrogen (N) has the electronic configuration: \( 1s^2 2s^2 2p^3 \)
  • Oxygen (O) has the electronic configuration: \( 1s^2 2s^2 2p^4 \)

However, since \( NO \) has 11 total valence electrons, removing one electron for the \( NO^+ \) ion leaves us with 10 valence electrons. The filling of molecular orbitals would be:

  • \( \sigma_{1s}^2 \sigma_{1s}^2 \)
  • \( \sigma_{2s}^2 \sigma_{2s}^2 \)
  • \( \sigma_{2p_z}^2 \)
  • \( \pi_{2p_x}^2 \pi_{2p_y}^2 \)

Thus, the configuration for \( NO^+ \) is: \[ ( \sigma_{1s}^2) ( \sigma_{1s}^2) ( \sigma_{2s}^2) ( \sigma_{2s}^2) ( \sigma_{2p_z}^2) ( \pi_{2p_x}^2) ( \pi_{2p_y}^2) \]

Bond Order Calculation: Bond Order = \( \frac{(Number , of , bonding , electrons - Number , of , anti-bonding , electrons)}{2} \)

  • Bonding Electrons = 10 (from filled orbitals)
  • Anti-bonding Electrons = 0.

Bond Order = \( \frac{10 - 0}{2} = 5\)

Number of Bonding and Anti-bonding Electrons:

  • Number of bonding electrons = 10
  • Number of anti-bonding electrons = 0

Summary

  1. Carbon Monoxide (CO)

    • Bond Order: 3
    • Molecular Configuration: \( \sigma_{1s}^2 \sigma_{1s}^2 \sigma_{2s}^2 \sigma_{2s}^2 \sigma_{2p_z}^2 \pi_{2p_x}^2 \pi_{2p_y}^2 \)
    • Number of Bonding Electrons: 10
    • Number of Anti-bonding Electrons: 0
  2. Nitrosonium Ion (NO⁺)

    • Bond Order: 3
    • Molecular Configuration: \( \sigma_{1s}^2 \sigma_{1s}^2 \sigma_{2s}^2 \sigma_{2s}^2 \sigma_{2p_z}^2 \pi_{2p_x}^2 \pi_{2p_y}^2 \)
    • Number of Bonding Electrons: 10
    • Number of Anti-bonding Electrons: 0