Praseodymium vs Meitnerium

PropertyPr PraseodymiumMt Meitnerium
Atomic number59109
SymbolPrMt
NamePraseodymiumMeitnerium
Categorylanthanidetransition-metal
Standard Atomic Weight140.90766 u278 u
Period67
GroupN/A9
Blockss
Phase at STPsolidN/A
Electron configuration[Xe]6s24f3[Rn]7s25f146d7(calculated)
Oxidation states[0, 1, 2, 3, 4, 5][1, 3, 4, 6, 8, 9]
Electronegativity (Pauling)1.13N/A
Electron affinity0.962 eV1.7 eV
Density6770 kg/m³3.740000e+4 kg/m³
Melting point930.85 °C-273.15 °C
Boiling point3519.85 °C-273.15 °C
Discovery year18851982