Chemistry Q&A

What is the bond order of O₂?

Answer

The bond order of O₂ is 2.

Using Molecular Orbital Theory, bond order = ½ (Nᵦ − Nₐ).

For O₂, this evaluates to 2, consistent with a double-bond picture.

MOT also shows two unpaired electrons in π* orbitals, so O₂ is paramagnetic — an important JEE/NEET point.

Example · O₂⁺ has a higher bond order than O₂; O₂⁻ has a lower bond order than O₂.

Exam Trap: Do not say O₂ is diamagnetic; experiment and MOT both show it is paramagnetic.

Relevant for: JEE · NEET