Atomic Number 56     Atomic Mass 137.327     Density 3.51 g/mL     State solid    

Color silvery white     Electronegativity 0.89    

Melting Point 725°C     Boiling Point 1640°C

Natural Isotopes Ba-130 0.106% Ba-132 0.101% Ba-134 2.417%

Ba-135 6.592% Ba-136 7.854% Ba-137 11.23% Ba-138 71.70%

Abbreviated Electron Configuration [Xe] 6s²    

Discovered by Sir Humphrey Davy in 1808.