Samarium vs Americium

PropertySm SamariumAm Americium
Atomic number6295
SymbolSmAm
NameSamariumAmericium
Categorylanthanideactinide
Standard Atomic Weight150.36 u243 u
Period67
GroupN/AN/A
Blockss
Phase at STPsolidsolid
Electron configuration[Xe]6s24f6[Rn]7s25f7
Oxidation states[0, 1, 2, 3][2, 3, 4, 5, 6, 7]
Electronegativity (Pauling)1.171.3
Electron affinity0.156 eV0.1 eV
Density7520 kg/m³1.369000e+4 kg/m³
Melting point1073.85 °C1175.85 °C
Boiling point1793.85 °C2010.85 °C
Discovery year18781944