Terbium vs Thorium

PropertyTb TerbiumTh Thorium
Atomic number6590
SymbolTbTh
NameTerbiumThorium
Categorylanthanideactinide
Standard Atomic Weight158.92535 u232.0377 u
Period67
GroupN/AN/A
Blockss
Phase at STPsolidsolid
Electron configuration[Xe]6s24f9[Rn]7s26d2
Oxidation states[0, 1, 2, 3, 4][-1, 1, 2, 3, 4]
Electronegativity (Pauling)N/A1.3
Electron affinity1.124 eV0.607 eV
Density8230 kg/m³1.172000e+4 kg/m³
Melting point1355.85 °C1749.85 °C
Boiling point3229.85 °C4787.85 °C
Discovery year18431828