Niobium vs Roentgenium

PropertyNb NiobiumRg Roentgenium
Atomic number41111
SymbolNbRg
NameNiobiumRoentgenium
Categorytransition-metaltransition-metal
Standard Atomic Weight92.90637 u281 u
Period57
Group511
Blockss
Phase at STPsolidN/A
Electron configuration[Kr]5s14d4[Rn] 7s2 5f14 6d9(predicted)
Oxidation states[-3, -1, 0, 1, 2, 3, 4, 5][-1, 1, 3, 5]
Electronegativity (Pauling)1.6N/A
Electron affinity0.893 eV1.6 eV
Density8570 kg/m³2.870000e+4 kg/m³
Melting point2476.85 °C-273.15 °C
Boiling point4743.85 °C-273.15 °C
Discovery year18011994