SymbolFm
Latin nameFermium
Atomic number100
Period7
Element categoryInner transition elements
Relative atomic mass257.0951
GroupIII.B
Oxidation numbers
2, 3
Electron configuration
1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 5s2 5p6 4f14 5d10 6s2 6p6 5f12 6d0 7s2
State
Solid
Thermal conductivity [W m-1K-1]
10
Discovery
1954
1.st ionization energy [eV]
6.5
Stable isotopes
0
Unstable isotopes
10