Iridium vs Polonium

PropertyIr IridiumPo Polonium
Atomic number7784
SymbolIrPo
NameIridiumPolonium
Categorytransition-metalmetalloid
Standard Atomic Weight192.217 u209 u
Period66
Group916
Blocksp
Phase at STPsolidsolid
Electron configuration[Xe]6s24f145d7[Xe]6s24f145d106p4
Oxidation states[-3, -2, -1, 1, 2, 3, 4, 5, 6, 7, 8, 9][-2, 2, 4, 5, 6]
Electronegativity (Pauling)2.22
Electron affinity1.565 eV1.9 eV
Density2.256220e+4 kg/m³9320 kg/m³
Melting point2445.85 °C253.85 °C
Boiling point4427.85 °C961.85 °C
Discovery year18031898