Actinium vs Uranium

PropertyAc ActiniumU Uranium
Atomic number8992
SymbolAcU
NameActiniumUranium
Categoryactinideactinide
Standard Atomic Weight227 u238.02891 u
Period77
GroupN/AN/A
Blockss
Phase at STPsolidsolid
Electron configuration[Rn]7s26d1[Rn]7s25f36d1
Oxidation states[3][-1, 1, 2, 3, 4, 5, 6]
Electronegativity (Pauling)1.11.38
Electron affinity0.35 eV0.3 eV
Density1.007000e+4 kg/m³1.895000e+4 kg/m³
Melting point1050.85 °C1134.85 °C
Boiling point3197.85 °C4130.85 °C
Discovery year18991789