Polonium vs Meitnerium

PropertyPo PoloniumMt Meitnerium
Atomic number84109
SymbolPoMt
NamePoloniumMeitnerium
Categorymetalloidtransition-metal
Standard Atomic Weight209 u278 u
Period67
Group169
Blockps
Phase at STPsolidN/A
Electron configuration[Xe]6s24f145d106p4[Rn]7s25f146d7(calculated)
Oxidation states[-2, 2, 4, 5, 6][1, 3, 4, 6, 8, 9]
Electronegativity (Pauling)2N/A
Electron affinity1.9 eV1.7 eV
Density9320 kg/m³3.740000e+4 kg/m³
Melting point253.85 °C-273.15 °C
Boiling point961.85 °C-273.15 °C
Discovery year18981982