What characteristic is associated with the last column of each block in the periodic table?

The last column of each block in the periodic table corresponds to specific groups of elements that exhibit a particular electronic configuration. These groups include the noble gases in Group 18 and the transition metals in their respective blocks. The elements in these groups often have completely filled electron shells or subshells, which leads to a stable electron configuration.

As a result, the elements in the last column of each block are generally diamagnetic. This characteristic means that they are not attracted to a magnetic field and do not exhibit unpaired electrons that could interact with magnetic fields. The presence of paired electrons in their outermost energy levels contributes to this diamagnetic property.

For instance, noble gases such as helium (He), neon (Ne), and argon (Ar) have full outer electron shells, leading to no unpaired electrons. This stability and lack of magnetic interaction are key signs of diamagnetism. Consequently, elements found in the last column across the blocks will demonstrate this property, distinguishing them from other elements that may possess unpaired electrons and therefore show paramagnetic behavior.