Potassium vs Americium

PropertyK PotassiumAm Americium
Atomic number1995
SymbolKAm
NamePotassiumAmericium
Categoryalkali-metalactinide
Standard Atomic Weight39.0983 u243 u
Period47
Group1N/A
Blockss
Phase at STPsolidsolid
Electron configuration[Ar]4s1[Rn]7s25f7
Oxidation states[-1, 1][2, 3, 4, 5, 6, 7]
Electronegativity (Pauling)0.821.3
Electron affinity0.5014 eV0.1 eV
Density890 kg/m³1.369000e+4 kg/m³
Melting point63.38 °C1175.85 °C
Boiling point758.85 °C2010.85 °C
Discovery year18071944