Einsteinium was discovered in December 1952 by Albert Ghiorso and co-workers at Berkeley Laboratories, University of California, USA.
Name: Einsteinium
Symbol: Es
Atomic number: 99
Atomic weight: 252.08
State: solid
Group, period, block: n/a, 7, f
Color: silver-colored
Classification: actinide
Electron configuration: 5f11 7s2
2,8,18,32,29,8,2
Physical properties
Density: 8.84 g/cm-3
Melting point: 1133 K,860 °C,1580 °F
Boiling point: no data
Atomic properties
Oxidation states: 2, 3, 4
Electronegativity: 1.3 (Pauling scale)
Ionization energies: 1st: 619 kJ·mol-1
Covalent radius: no data
Van der Waals radius: no data
- Es
Electron Configuration
Isotopes
Einsteinium has no stable isotopes. The first isotope to be discovered was 253Es in 1952.