# How can elements achieve a stable electron configurations?

Helium (He), in Period 1, is the first noble gas and has an electron configuration of ${\text{1s}}^{2}$. The atoms of the element hydrogen (H) (${\text{1s}}^{1}$) typically share one electron with another hydrogen atom, or an atom of another element, in order to achieve the noble gas configuration of helium.
In Period 2, lithium atoms (${\text{1s"^2"2s}}^{1}$) in Group 1 lose their single valence electron to become a positively charged 1+ ion, and beryllium atoms ($\text{1s"^2"2s"^2}$) in Group 2 will lose their two valence electrons to become 2+ ions. After losing their valence electrons, lithium and beryllium ions will have the noble gas configuration of helium in Period 1. The atoms of the rest of the representative elements (Groups 13-17) in Period 2 will gain, lose, or share electrons in order to achieve the noble gas of Neon ($\text{1s"^2"2s"^2"2p"^6}$) at the end of Period 2.