#20 CalciumCalcium is classified chemically as one of the alkaline earth elements (that is, in Group 2 of the periodic table. The metal is rather reactive. It readily forms a white coating of calcium nitride (Ca3N2) in air. Atomic mass:40.078 amu Melting point:839.0 C (1112.15 K, 1542.2 F) Boiling point:1484.0 C (1757.15 K, 2703.2 F) Density:293 K: 1.55 g/cm3 |