Americium vs Curium

PropertyAm AmericiumCm Curium
Atomic number9596
SymbolAmCm
NameAmericiumCurium
Categoryactinideactinide
Standard Atomic Weight243 u247 u
Period77
GroupN/AN/A
Blockss
Phase at STPsolidsolid
Electron configuration[Rn]7s25f7[Rn]7s25f76d1
Oxidation states[2, 3, 4, 5, 6, 7][3, 4, 5, 6]
Electronegativity (Pauling)1.31.3
Electron affinity0.1 eV0.277 eV
Density1.369000e+4 kg/m³1.351000e+4 kg/m³
Melting point1175.85 °C1344.85 °C
Boiling point2010.85 °C3126.85 °C
Discovery year19441944