Krypton vs Polonium

PropertyKr KryptonPo Polonium
Atomic number3684
SymbolKrPo
NameKryptonPolonium
Categorynoble-gasmetalloid
Standard Atomic Weight83.798 u209 u
Period46
Group1816
Blockpp
Phase at STPgassolid
Electron configuration[Ar]4s23d104p6[Xe]6s24f145d106p4
Oxidation states[0, 1, 2][-2, 2, 4, 5, 6]
Electronegativity (Pauling)32
Electron affinity-1 eV1.9 eV
Density3.733 kg/m³9320 kg/m³
Melting point-157.36 °C253.85 °C
Boiling point-153.42 °C961.85 °C
Discovery year18981898