NEET2026ChemistryChapterActual
Which of the following statements is correct according to Molecular Orbital Theory?
Options
- AThe B₂ molecule is diamagnetic in nature because it contains an even number of electrons.
- BThe species N₂^+ and N₂^- have identical bond orders, but N₂^+ is more stable than N₂^- .
- CIn the O₂ molecule, the energy of the _ 2p_z molecular orbital is higher than that of the degenerate _ 2p_x an
- DThe He₂^+ ion has a calculated bond order of 1.0 .
Correct answer
B. The species N₂^+ and N₂^- have identical bond orders, but N₂^+ is more stable than N₂^- .
Step-by-step solution
For the B₂ molecule, the total number of electrons is 10 . The molecular orbital electronic configuration is _ 1s ² _ 1s ^ *2 _ 2s ² _ 2s ^ *2 _ 2p_x ¹ = _ 2p_y ¹ . Due to the presence of two unpaired electrons, B₂ is paramagnetic. Thus, statement (A) is incorrect. For N₂⁺ , the total number of electrons is 13 . The bond order is 1 2 (9 - 4) = 2.5 . For N₂⁻ , the total number of electrons is 15 . The bond order is 1 2 (10 - 5) = 2.5 . Both species have the same bond order, but N₂⁻ has more electrons in antibonding