Terbium vs Meitnerium

PropertyTb TerbiumMt Meitnerium
Atomic number65109
SymbolTbMt
NameTerbiumMeitnerium
Categorylanthanidetransition-metal
Standard Atomic Weight158.92535 u278 u
Period67
GroupN/A9
Blockss
Phase at STPsolidN/A
Electron configuration[Xe]6s24f9[Rn]7s25f146d7(calculated)
Oxidation states[0, 1, 2, 3, 4][1, 3, 4, 6, 8, 9]
Electronegativity (Pauling)N/AN/A
Electron affinity1.124 eV1.7 eV
Density8230 kg/m³3.740000e+4 kg/m³
Melting point1355.85 °C-273.15 °C
Boiling point3229.85 °C-273.15 °C
Discovery year18431982