Praseodymium vs Roentgenium

PropertyPr PraseodymiumRg Roentgenium
Atomic number59111
SymbolPrRg
NamePraseodymiumRoentgenium
Categorylanthanidetransition-metal
Standard Atomic Weight140.90766 u281 u
Period67
GroupN/A11
Blockss
Phase at STPsolidN/A
Electron configuration[Xe]6s24f3[Rn] 7s2 5f14 6d9(predicted)
Oxidation states[0, 1, 2, 3, 4, 5][-1, 1, 3, 5]
Electronegativity (Pauling)1.13N/A
Electron affinity0.962 eV1.6 eV
Density6770 kg/m³2.870000e+4 kg/m³
Melting point930.85 °C-273.15 °C
Boiling point3519.85 °C-273.15 °C
Discovery year18851994