Quite a few are missed off: what about germanium, arsenic, selenium, bromine, strontium and barium? Different ways of representing the lanthanides and actinides may cause strontium and barium to be missed off (or more to be added on) but I think germanium, arsenic, selenium and bromine are indisputable.
Great idea, was there a reason that the ones mentioned by others (+polonium) were left out? Genuine question (as opposed to nit-picking) as there may be a science-y answer that I’m not aware of! Lol