Astatine vs Meitnerium

PropertyAt AstatineMt Meitnerium
Atomic number85109
SymbolAtMt
NameAstatineMeitnerium
Categoryhalogentransition-metal
Standard Atomic Weight210 u278 u
Period67
Group179
Blockps
Phase at STPsolidN/A
Electron configuration[Xe]6s24f145d106p5[Rn]7s25f146d7(calculated)
Oxidation states[-1, 1, 3, 5, 7][1, 3, 4, 6, 8, 9]
Electronegativity (Pauling)2.2N/A
Electron affinity2.391 eV1.7 eV
Density7000 kg/m³3.740000e+4 kg/m³
Melting point301.85 °C-273.15 °C
Boiling point-273.15 °C-273.15 °C
Discovery year19401982