Tantalum vs Americium

PropertyTa TantalumAm Americium
Atomic number7395
SymbolTaAm
NameTantalumAmericium
Categorytransition-metalactinide
Standard Atomic Weight180.94788 u243 u
Period67
Group5N/A
Blockss
Phase at STPsolidsolid
Electron configuration[Xe]6s24f145d3[Rn]7s25f7
Oxidation states[-3, -1, 0, 1, 2, 3, 4, 5][2, 3, 4, 5, 6, 7]
Electronegativity (Pauling)1.51.3
Electron affinity0.322 eV0.1 eV
Density1.640000e+4 kg/m³1.369000e+4 kg/m³
Melting point3016.85 °C1175.85 °C
Boiling point5457.85 °C2010.85 °C
Discovery year18021944