Es
Einsteinium
Atomic number: 99Mass: 252 uCategory: Actinide
About Einsteinium
Einsteinium is a synthetic element produced in nuclear reactors or by bombarding lighter elements with neutrons. It was named after Albert Einstein. It was discovered in the debris of the first hydrogen bomb test.
Properties
Period
7
Group
N/A
Block
F
Category
Actinide
Electronegativity
1.30 (Pauling)
Ionization Energy
619 kJ/mol
Melting Point
1133 K (860°C)
Boiling Point
1269 K (996°C)
Density
8.84 g/cm³
Oxidation States
+2, +3
Electron Configuration
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 6s² 6p⁶ 5f¹¹ 7s²
[Rn] 5f¹¹ 7s²
Shell 1:2e⁻
Shell 2:8e⁻
Shell 3:18e⁻
Shell 4:32e⁻
Shell 5:29e⁻
Shell 6:8e⁻
Shell 7:2e⁻
Real-World Uses
Research only
Synthesis of heavier elements (mendelevium)
Fundamental physics studies
No practical applications
Nuclear science
Fun Fact
Einsteinium was first discovered in the fallout of the first hydrogen bomb explosion in 1952 — scientists found it in the radioactive debris!