Many of these elements are (*) paramagnetic, most have multiple oxidation states, and they include the lanthanides and actinides.
One of these elements is more stable with a half-filled lower-energy shell than a partially-filled higher-energy shell, so it violates the Aufbau principle. Many of these elements are (*) paramagnetic, most have multiple oxidation states, and they include the lanthanides and actinides. Groups 3 through 12 are, for 10 points, what f- and d-block elements, which are shown in the middle of the periodic table?
One of these elements is more stable with a half-filled lower-energy shell than a partially-filled higher-energy shell, so it violates the Aufbau principle.
transition metals (accept transition elements; accept copper before "lanthanides"; prompt on metals)