Osmium vs Curium

PropertyOs OsmiumCm Curium
Atomic number7696
SymbolOsCm
NameOsmiumCurium
Categorytransition-metalactinide
Standard Atomic Weight190.23 u247 u
Period67
Group8N/A
Blockss
Phase at STPsolidsolid
Electron configuration[Xe]6s24f145d6[Rn]7s25f76d1
Oxidation states[-4, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8][3, 4, 5, 6]
Electronegativity (Pauling)2.21.3
Electron affinity1.1 eV0.277 eV
Density2.258720e+4 kg/m³1.351000e+4 kg/m³
Melting point3032.85 °C1344.85 °C
Boiling point5011.85 °C3126.85 °C
Discovery year18031944