The alkaline earth metals are six chemical elements in column (group) 2 of the Periodic table. They are beryllium (Be), magnesium (Mg),calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra). They have very similar properties: they are all shiny, silvery-white, somewhatreactive metals at standard temperature and pressure.
Structurally, they have in common an outer s- electron shell which is full; that is, this orbital contains its full complement of two electrons, which these elements readily lose to form cations with charge +2, and an oxidation state (oxidation number) of +2.
All the discovered alkaline earth metals occur in nature. Experiments have been conducted to attempt the synthesis of element 120, the next potential member of the group, but they have all met with failure