Niobium vs Technetium

PropertyNb NiobiumTc Technetium
Atomic number4143
SymbolNbTc
NameNiobiumTechnetium
Categorytransition-metaltransition-metal
Standard Atomic Weight92.90637 u98 u
Period55
Group57
Blockss
Phase at STPsolidsolid
Electron configuration[Kr]5s14d4[Kr]5s24d5
Oxidation states[-3, -1, 0, 1, 2, 3, 4, 5][-3, -1, 1, 2, 3, 4, 5, 6, 7]
Electronegativity (Pauling)1.61.9
Electron affinity0.893 eV0.55 eV
Density8570 kg/m³1.100000e+4 kg/m³
Melting point2476.85 °C2156.85 °C
Boiling point4743.85 °C4264.85 °C
Discovery year18011937