Attribute | Berkelium × | Einsteinium × |
---|---|---|
Atomic mass (u) | 247.07031 | 252.083 |
Standard state | Solid | Solid |
Oxidation states |
|
|
1↓Electron configuration | [Rn]7s²5f⁹ | [Rn]7s²5f¹¹ |
Atomic radius (van der waals) (pm) | 244 | 245 |
Electronegativity (pauling scale) | 1.3 | 1.3 |
Melting point (K) | 1323 | 1133 |
Ionization energy (eV) | 6.23 | 6.42 |
Density (g/cm³) | 14 | - |
Atomic number | 97 | 99 |
Group name | Actinide | Actinide |
Symbol | Bk | Es |
Discovered (year) | 1949 | 1952 |