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Fm

Fermium

Atomic number: 100Mass: 257 uCategory: Actinide

About Fermium

Fermium is a synthetic element created by bombarding lighter elements with neutrons. It was named after nuclear physicist Enrico Fermi. Like einsteinium, it was discovered in debris from the first hydrogen bomb test.

Properties

Period
7
Group
N/A
Block
F
Category
Actinide
Electronegativity
1.30 (Pauling)
Ionization Energy
627 kJ/mol
Melting Point
1800 K (1527°C)
Boiling Point
Unknown
Density
Unknown
Oxidation States
+2, +3

Electron Configuration

1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰ 4f¹⁴ 5s² 5p⁶ 5d¹⁰ 6s² 6p⁶ 5f¹² 7s²
[Rn] 5f¹² 7s²
Shell 1:2e⁻
Shell 2:8e⁻
Shell 3:18e⁻
Shell 4:32e⁻
Shell 5:30e⁻
Shell 6:8e⁻
Shell 7:2e⁻

Real-World Uses

Research only
Scientific study of actinide properties
Atomic structure research
No practical applications
Nuclear physics

Fun Fact

Fermium was also discovered hidden in the debris of a hydrogen bomb blast — two elements discovered from a single nuclear explosion!