Selenium vs Curium

PropertySe SeleniumCm Curium
Atomic number3496
SymbolSeCm
NameSeleniumCurium
Categorynonmetalactinide
Standard Atomic Weight78.971 u247 u
Period47
Group16N/A
Blockps
Phase at STPsolidsolid
Electron configuration[Ar]4s23d104p4[Rn]7s25f76d1
Oxidation states[-2, -1, 0, 1, 2, 3, 4, 5, 6][3, 4, 5, 6]
Electronegativity (Pauling)2.551.3
Electron affinity2.0206 eV0.277 eV
Density4809 kg/m³1.351000e+4 kg/m³
Melting point220.5 °C1344.85 °C
Boiling point684.85 °C3126.85 °C
Discovery year18171944