Lutetium vs Actinium

PropertyLu LutetiumAc Actinium
Atomic number7189
SymbolLuAc
NameLutetiumActinium
Categorylanthanideactinide
Standard Atomic Weight174.9668 u227 u
Period67
Group3N/A
Blockss
Phase at STPsolidsolid
Electron configuration[Xe]6s24f145d1[Rn]7s26d1
Oxidation states[0, 1, 2, 3][3]
Electronegativity (Pauling)1.271.1
Electron affinity0.346 eV0.35 eV
Density9840 kg/m³1.007000e+4 kg/m³
Melting point1662.85 °C1050.85 °C
Boiling point3401.85 °C3197.85 °C
Discovery year19071899