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).[1] They have very similar properties: they are all shiny, silvery-white, somewhatreactive metals at standard temperature and pressure.[2]

Structurally, they have in common an outer s- electron shell which is full;[2][3][4] 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.[5]

All the discovered alkaline earth metals occur in nature.[6] 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

1 they have valency 2
2 they have 2 valence electrons
3 their oxides are basic in nature
4 they are electropositive