Attribute | Mendelevium × | Berkelium × |
---|---|---|
Atomic mass (u) | 258.09843 | 247.07031 |
Standard state | Solid | Solid |
Oxidation states |
|
|
Electron configuration | [Rn]7s²5f¹³ | [Rn]7s²5f⁹ |
Atomic radius (van der waals) (pm) | - | 244 |
Electronegativity (pauling scale) | 1.3 | 1.3 |
Melting point (K) | 1100 | 1323 |
1↓Ionization energy (eV) | 6.58 | 6.23 |
Density (g/cm³) | - | 14 |
Atomic number | 101 | 97 |
Group name | Actinide | Actinide |
Symbol | Md | Bk |
Discovered (year) | 1955 | 1949 |