What is the difference between naming ionic compounds and ones that contain transitional metals?

Transition metals often have multiple charges, for example Copper can be a +1 or a +2 charge. When you name something with multiple charges you need to indicate the charge using either roman numerals (stock system) or by changing the suffix of the name (classical system).





FeO is Iron (II) Oxide or ferrous oxide


Fe2O3 is Iron (III) Oxide or ferric oxide