Atomic number:95

Group numbers:3

Period:7

Electronic configuration:[Rn] 5f⁷ 7s²

Formal oxidation number:+3 +4 +5 +6

Electronegativities:-

Atomic radius / pm:173

Relative atomic mass:[243]

 

Americium was discovered by Glenn T. Seaborg, Ralph A. James, Leon O. Morgan, and Albert Ghiorso (US) in 1944. Named for the American continent. It is a silvery-white, artificially produced radioactive metal. Americium was produced by bombarding plutonium with neutrons. Americium-241 is currently used in smoke detectors.

Density / g dm^-3:13670 (293 K)

Molar volume / cm³mol^-1:17.78 (293 K)

Electrical resistivity / μΩcm:68 (20 °C)

Thermal conductivity / W m^-1K^-1:10

Melting point / °C:1176

Boiling point / °C:2011

Heat of fusion / kJ mol^-1:14.4

Heat of vaporization / kJ mol^-1:238.5

Heat of atomization / kJ mol^-1:266

1st ionization energy / kJ mol^-1:576.39

2nd ionization energy / kJ mol^-1:-

3rd ionization energy / kJ mol^-1:-

in the atmosphere / ppm:-

in the Earth's crust / ppm:-

in the oceans / ppm:-