Atomic Number 34     Atomic Mass 78.96     Density 4.81 g/mL

State solid     Color metallic grey      Electronegativity 2.55

Melting Point 217°C     Boiling Point 684.9°C

Natural Isotopes Se-74 0.89%   Se-76 9.36%   Se-77 7.63%
                        Se-78 23.78%   Se-80 49.61%   Se-82 8.73%

Abbreviated Electron Configuration [Ar] 3d¹⁰ 4s² 4p⁴

Discovered by Jons Berzelius in 1817.