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This paper replies to two of the most common questions that students usually pose to their teacher during a general chemistry course, i.e. how many chemical elements are in the Periodic Table and how many could be in our Universe. Reply to the former question can be easily found either in the literature or in any updated chemistry book. More interestingly, this communication shows that the latter question may be (simply) answered by making reference to the Bohr’s atomic model that, notwithstanding its well-known limits, allows teachers to demonstrate that (for a hydrogenoid atom) 137 is the highest possible value for Z, as predicted by quantum electrodynamics, a much more complicated theory, usually taught in Physics advanced courses.

How Many Chemical Elements are there in the Universe? A (not so) <i>Bohring</i> Question