100 Fm (Fermium)
Mass number – 257
Atomic weight – 257.0951 g/mol
Atomic number (Z) – 100
Electrons: 100
Protons: 100
Neutrons: 157
Period – 7
Block – f
Element category – Actinide
Electrons per shell – K2, L8, M18, 32, O30, P8, Q2
Electron configuration – 1s22s22p63s23p63d104s24p64d105s25p64f145d106s26p65f127s2
Phase – Solid
Melting point – 1800 k (1527 oC)
Density – 9.7(1) g/cm3
Half Life(s) – 8683000
LifeTime(s) – 12530000
Appearance – Radioactive metal
Oxidation states – 2, 3
Electnegativity – Pauling scale 1:3
Ionization energies – 1st: 627 kJ/mol
Crystal structure – Face-centered cubic
CAS Number – 7440-72-4
Naming – After Enrico Fermi
Discovery – Lawrence Berkeley National Laboratory (1952)
Isotopes – 252Fm 253Fm 255Fm 257Fm
Uses – Fermium has no uses outside research
Biological role – Fermium is toxic due to its radioactivity.
Natural abundance – Fermium can be obtained, in microgram quantities, from the neutron bombardment of plutonium in a nuclear reactor
#Fermium