The arrangement of electrons in atoms is responsible for the shape of the periodic table. Valence electrons are those electrons in the highest energy level of an atom. Thus, the number of valence elec...The arrangement of electrons in atoms is responsible for the shape of the periodic table. Valence electrons are those electrons in the highest energy level of an atom. Thus, the number of valence electrons in one atom of an element can be easily determined by its position on the periodic table.
