100 Fm

Actinide

Fermium

Named after Fermi.

See it in the interactive periodic table

Properties of Fermium

Atomic number (Z)
100
Symbol
Fm
Atomic mass
257 g/mol
Category
Actinide
Group
3
Period
7
Electron configuration
[Rn] 5f¹² 7s²
Electronegativity (Pauling)
1.3
Atomic radius
First ionization energy
627 kJ/mol
Melting point
1800 K (1526.8 °C)
Boiling point
Density
Phase at 25 °C
Solid
Discovered
Discovered in 1952
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