Rubidium vs Polonium

PropertyRb RubidiumPo Polonium
Atomic number3784
SymbolRbPo
NameRubidiumPolonium
Categoryalkali-metalmetalloid
Standard Atomic Weight85.4678 u209 u
Period56
Group116
Blocksp
Phase at STPsolidsolid
Electron configuration[Kr]5s1[Xe]6s24f145d106p4
Oxidation states[-1, 1][-2, 2, 4, 5, 6]
Electronegativity (Pauling)0.822
Electron affinity0.4859 eV1.9 eV
Density1530 kg/m³9320 kg/m³
Melting point39.31 °C253.85 °C
Boiling point687.85 °C961.85 °C
Discovery year18611898