Why aren’t transition metals on the period table labelled as groups?

Question

Why aren’t transition metals on the period table labelled as groups?

In: 6

Answer 1

Groups on the periodic table denote elements that have similar chemical properties. The alkaline metals, for example, strongly favor forming +1 ions. Halogens strongly favor forming – 1 ions. The transition metals are unique because they can be stable in multiple oxidation states, which is the unifying commonality between them. Copper can form a 2+ ion, as can iron, yet they are not in the same column like the other groups. It’s useful to think of the transition metals as one large group