Polonium vs Berkelium

PropertyPo PoloniumBk Berkelium
Atomic number8497
SymbolPoBk
NamePoloniumBerkelium
Categorymetalloidactinide
Standard Atomic Weight209 u247 u
Period67
Group16N/A
Blockps
Phase at STPsolidsolid
Electron configuration[Xe]6s24f145d106p4[Rn]7s25f9
Oxidation states[-2, 2, 4, 5, 6][2, 3, 4, 5]
Electronegativity (Pauling)21.3
Electron affinity1.9 eV-0.5 eV
Density9320 kg/m³1.400000e+4 kg/m³
Melting point253.85 °C1049.85 °C
Boiling point961.85 °C-273.15 °C
Discovery year18981949