Polonium vs Francium

PropertyPo PoloniumFr Francium
Atomic number8487
SymbolPoFr
NamePoloniumFrancium
Categorymetalloidalkali-metal
Standard Atomic Weight209 u223 u
Period67
Group161
Blockps
Phase at STPsolidsolid
Electron configuration[Xe]6s24f145d106p4[Rn]7s1
Oxidation states[-2, 2, 4, 5, 6][1]
Electronegativity (Pauling)20.7
Electron affinity1.9 eV0.491 eV
Density9320 kg/m³1870 kg/m³
Melting point253.85 °C26.85 °C
Boiling point961.85 °C-273.15 °C
Discovery year18981939