NEETChemistryChemical Bonding and Molecular Structure
In the ground state of an oxygen ( O₂ ) molecule, the unpaired electrons occupy specific molecular orbitals. Which of the following correctly describes the nature and symmetry of these molecular orbitals with respect to the internuclear axis?
Options
- AThey are antibonding molecular orbitals, which are unsymmetrical around the internuclear axis.
- BThey are antibonding molecular orbitals, which are symmetrical around the internuclear axis.
- CThey are antibonding molecular orbitals, which are symmetrical around the internuclear axis.
- DThey are bonding molecular orbitals, which are unsymmetrical around the internuclear axis.
Correct answer
A. They are antibonding molecular orbitals, which are unsymmetrical around the internuclear axis.
Step-by-step solution
The electronic configuration of an O₂ molecule (16 electrons) according to Molecular Orbital Theory is: 1s^2 ^ * 1s^2 2s^2 ^ * 2s^2 2p_z^2 ( 2p_x^2 = 2p_y^2) ( ^ * 2p_x^1 = ^ * 2p_y^1) The two unpaired electrons are present in the ^ * 2p_x and ^ * 2p_y molecular orbitals. These are antibonding molecular orbitals. According to MOT, all molecular orbitals (both bonding and antibonding) have zero electron density along the internuclear axis and are unsymmetrical around the internuclear axis. Therefore, the unpaired el