Which of the following molecules is paramagnetic?

Question

Quizplus · Accepted Answer

To determine if a molecule is paramagnetic, we need to determine if it has any unpaired electrons. We can do so by filling up the molecular orbitals with electrons and applying Hund's rule. Upon doing so, we find that molecule B (O₂) has two unpaired electrons in its pi* antibonding molecular orbital, making it paramagnetic. The other molecules have all of their electrons paired, so they are diamagnetic. Note: the quotation marks in option E are not needed, as they do not represent a legitimate difference in the molecule's identity.

Which of the Following Molecules Is Paramagnetic