Fermium - Fm General Information Discovery Fermium was discovered by G. R. Choppin, S.G. Thompson, A. Ghiorso and B.G. Harvey in 1952, in the debris of the thermonuclear explosion at Eniwetok in the Pacific. This involved the examination of tons of radioactive coral from the blast area. Appearance Fermium has a very short life-span, so scientists doubt that enough of the element will ever be obtained to be weighed or seen. Source Fermium can be obtained in microgram quantities from the neutron bombardment of plutonium. Uses Fermium has no uses outside research. Biological Role Fermium has no known biological role. It is toxic due to its radioactivity.

	Physical Information
	Atomic Number		100
	Relative Atomic Mass (12C=12.000)		257 (radioactive)
	Melting Point/K		not available
	Boiling Point/K		not available
	Density/kg m-3		(293K)
	Ground State Electron Configuration		[Rn]5f127s2
	Electron Affinity(M-M-)/kJ mol-1		not available

	Key Isotopes
	nuclide	254Fm	255Fm	257Fm
	atomic mass
	natural abundance	0%	0%	0%
	half-life	3.24 h	20 h	80 days

Other Information
Enthalpy of Fusion/kJ mol-1		n/a
Enthalpy of Vaporisation/kJ mol-1		n/a
Oxidation States
FmII, FmIII
Covalent Bonds /kJ mol-1
not applicable

	Ionisation Energies/kJ mol-1
	M - M+	627
	M+ - M2+
	M2+ - M3+
	M3+ - M4+
	M4+ - M5+
	M5+ - M6+
	M6+ - M7+
	M7+ - M8+
	M8+ - M9+
	M9+ - M10+