Hafnium vs Tantalum

PropertyHf HafniumTa Tantalum
Atomic number7273
SymbolHfTa
NameHafniumTantalum
Categorytransition-metaltransition-metal
Standard Atomic Weight178.49 u180.94788 u
Period66
Group45
Blockss
Phase at STPsolidsolid
Electron configuration[Xe]6s24f145d2[Xe]6s24f145d3
Oxidation states[-2, 0, 1, 2, 3, 4][-3, -1, 0, 1, 2, 3, 4, 5]
Electronegativity (Pauling)1.31.5
Electron affinity0.178 eV0.322 eV
Density1.330000e+4 kg/m³1.640000e+4 kg/m³
Melting point2232.85 °C3016.85 °C
Boiling point4602.85 °C5457.85 °C
Discovery year19111802