Attribute | Einsteinium × | Astatine × |
---|---|---|
Standard state | Solid | Solid |
Electron configuration | [Rn]7s²5f¹¹ | [Xe]6s²4f¹⁴5d¹⁰6p⁵ |
Atomic mass (u) | 252.083 | 209.98715 |
Electronegativity (pauling scale) | 1.3 | 2.2 |
Oxidation states |
|
|
Ionization energy (eV) | 6.42 | 9.5 |
1↓Atomic radius (van der waals) (pm) | 245 | 202 |
Melting point (K) | 1133 | 575 |
Electron affinity (eV) | - | 2.8 |
Density (g/cm³) | - | 7 |
Atomic number | 99 | 85 |
Group name | Actinide | Halogen |
Symbol | Es | At |
Discovered (year) | 1952 | 1940 |