Radium |
| Symbol | Ra |
|---|---|
| Latin name | Radium |
| Atomic number | 88 |
| Period | 7 |
| Element category | Alkaline earth metals |
| Relative atomic mass | 226.0254 |
| Group | II.A |
| Electronegativity | 0.9 |
| Oxidation numbers | 2 |
| Electron configuration | 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 7s2 |
| Density [g/cm3] | 5.5 |
| State | Solid |
| Melting point [°C] | 700 |
| Boiling point [°C] | 1140 |
| Thermal conductivity [W m-1K-1] | 18.6 |
| Heat capacity [J K-1g-1] | 0.094 |
| Discovery | 1898 |
| Electrical conductivity [S m-1] | 106 |
| 1.st ionization energy [eV] | 5.2789 |
| 2.nd ionization energy [eV] | 10.148 |
| Stable isotopes | 0 |
| Unstable isotopes | 16 |