How does the electronic configuration of an atom relate to its position in the Modern Periodic Table ?

The position of an atom/element in the periodic table is related to the number of electrons in the outermost shell. In a given column or group, all elements have the same number of electrons in their outermost shells. For example, in group 2, all elements have two electrons in their outermost shell. In group 15, all elements have 5 electrons in their outermost shells.