Fermium was discovered in December 1952 by Albert Ghiorso and co-workers at the University of California at Berkeley. It was made by bombarding plutonium with neutrons.
Name: Fermium
Symbol: Fm
Atomic number: 100
Atomic weight: 257.10
State: solid
Group, period, block: n/a, 7, f
Color: unknown
Classification: actinide
Electron configuration: 5f12 7s2
2,8,18,32,30,8,2
Physical properties
Density: no data
Melting point: 1800 K,1527 °C,2781 °F
Boiling point: no data
Atomic properties
Oxidation states: 2, 3
Electronegativity: 1.3 (Pauling scale)
Ionization energies: 1st: 627 kJ·mol-1
Covalent radius: no data
Van der Waals radius: no data
- Fm
Electron Configuration
Isotopes
Fermium has no stable isotopes. The first isotope to be discovered was 255Fm in 1952.