Barium

Symbol | Ba
Latin name | Baryum
Atomic number | 56
Period | 6
Element category | Alkaline earth metals
Relative atomic mass | 137.327
Group | II.A
Electronegativity | 0.9
Oxidation numbers | 2
Electron configuration | 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 6s2
Density [g/cm3] | 3.5
State | Solid
Melting point [°C] | 725
Boiling point [°C] | 1640
Thermal conductivity [W m-1K-1] | 18.4
Heat capacity [J K-1g-1] | 0.204
Discovery | 1808
Hardness [Mohs scale] | 1.25
Young's modulus [GPa] | 13
Electrical conductivity [S m-1] | 2.8 · 106
Shear modulus [GPa] | 4.9
1.st ionization energy [eV] | 5.2117
2.nd ionization energy [eV] | 10.004
Stable isotopes | 7
Unstable isotopes | 17