100 Fm 257
Fermium
Actinide
Fermium (Fm) is a chemical element with atomic number 100, classified as a actinide. At room temperature it is a solid. It was discovered in 1952 by Albert Ghiorso et al..
Properties
- Atomic number
- 100
- Atomic mass
- 257 u
- Category
- Actinide
- Group
- 0
- Period
- 7
- Block
- f-block
- Electron configuration
- [Rn] 5f¹² 7s²
- Phase at STP
- Solid
- Density
- —
- Melting point
- 1800 K (1526.8 °C)
- Boiling point
- —
- Electronegativity
- 1.3
- Atomic radius
- —
- Ionization energy
- 6.5 eV
- Discovery
- 1952 · Albert Ghiorso et al.
Common uses
Research only
Did you know?
Named after Enrico Fermi and discovered in hydrogen bomb tests.