Expert: George Maxwell - 9/25/2007

Question
Why is there a big space on the top of the periodic table?


Answer
Hi, and thanks for your question.

Actually, there shouldn't be a "gap": it's just for convenience sake that we draw the table like that. Hydrogen and Helium are both unusual elements, in that they contain very few protons, electrons and neutrons. Hydrogn in particular has a unique atomic configurtion, and so is placed on its own at the top left of the table. The remaining shape of the periodic table is determined by the number of electrons that each element's atoms contain.

In other words, there's no "gap" at the top of the table, because there are no "missing" elements, it's just drawn that way to allow patterns of electron distribution in atoms to be seen more clearly.

Thanks aagain for your question.