The alkaline earth metals are a series of elements that make up Group 2 of the periodic table: beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba) and radium (Ra). The alkaline earth metals are a prime example of group trends in properties in the periodic table, with a trend of similar for behavior going down the group. Here is the number of Electrons per shell: Alkaline earth metals will react readily with halogens.