Diamagnetism help?

Question

Diamagnetic is defined as atoms or ions in which all the electrons are paired in filled shells so their magnetic fields effectively cancel each other. Now, I know N2 is diamagnetic because it was the answer to a question on a practice test that I took but O2 was also a choice and it seems to me that there are no unpaired electrons when oxygen is bonded to itself through a double bond. Am I wrong about this? Why is oxygen not diamagnetic?

Answer 1

It just so happens that O2 is a diradical, with two unpaired electrons. I do not know where to refer you for an answer.