Question #a7215

1 Answer
Jul 7, 2017

Put simply, the size of an atom.

Explanation:

To elaborate, the nucleus is infinitesimally small relative to the actual "space" an atom takes up due to the electron orbital(s) present. However, as more protons (and as a result electrons) are added, atomic radius increases from left to right and up to down.

The reasons for this are the effective nuclear charge increasing for the valence electrons until another core shell is full and in more shells in general being occupied, respectively.