Terbium vs Polonium

PropertyTb TerbiumPo Polonium
Atomic number6584
SymbolTbPo
NameTerbiumPolonium
Categorylanthanidemetalloid
Standard Atomic Weight158.92535 u209 u
Period66
GroupN/A16
Blocksp
Phase at STPsolidsolid
Electron configuration[Xe]6s24f9[Xe]6s24f145d106p4
Oxidation states[0, 1, 2, 3, 4][-2, 2, 4, 5, 6]
Electronegativity (Pauling)N/A2
Electron affinity1.124 eV1.9 eV
Density8230 kg/m³9320 kg/m³
Melting point1355.85 °C253.85 °C
Boiling point3229.85 °C961.85 °C
Discovery year18431898