Paramagnetism and Diamagnetism Worked Problem

Here is a worked example problem showing how to tell whether an element is paramagnetic or diamagnetic based on its electron configuration.

Problem

Which of the following elements would be expected to be paramagnetic? Diamagnetic?

He, Be, Li, N

Solution

All of the electrons are spin-paired in diamagnetic elements so their subshells are completed, causing them to be unaffected by magnetic fields. Paramagnetic elements are strongly affected by magnetic fields because their subshells are not completely filled with electrons. So, to determine whether the elements are paramagnetic or diamagnetic, write out the electron configuration for each element.

He: 1s² subshell is filled

Be: 1s²2s² subshell is filled

Li: 1s²2s¹ subshell is not filled

N: 1s²2s²2p³ subshell is not filled

Answer

Li and N are paramagnetic. He and Be are diamagnetic.