Question

Which of the following species is not paramagnetic?

Options

• O₂

• B₂

• NO

• CO

Answer 1

CO

Explanation:

Paramagnetic species have unpaired electrons, while diamagnetic species have all electrons paired. CO (carbon monoxide) has all paired electrons in its molecular orbitals, so it is diamagnetic and not paramagnetic. In contrast, O₂, B₂, and NO have unpaired electrons, making them paramagnetic.