Holmium vs Americium

PropertyHo HolmiumAm Americium
Atomic number6795
SymbolHoAm
NameHolmiumAmericium
Categorylanthanideactinide
Standard Atomic Weight164.93033 u243 u
Period67
GroupN/AN/A
Blockss
Phase at STPsolidsolid
Electron configuration[Xe]6s24f11[Rn]7s25f7
Oxidation states[0, 1, 2, 3][2, 3, 4, 5, 6, 7]
Electronegativity (Pauling)1.231.3
Electron affinity0.338 eV0.1 eV
Density8800 kg/m³1.369000e+4 kg/m³
Melting point1473.85 °C1175.85 °C
Boiling point2699.85 °C2010.85 °C
Discovery year18781944