Thorium vs Berkelium

PropertyTh ThoriumBk Berkelium
Atomic number9097
SymbolThBk
NameThoriumBerkelium
Categoryactinideactinide
Standard Atomic Weight232.0377 u247 u
Period77
GroupN/AN/A
Blockss
Phase at STPsolidsolid
Electron configuration[Rn]7s26d2[Rn]7s25f9
Oxidation states[-1, 1, 2, 3, 4][2, 3, 4, 5]
Electronegativity (Pauling)1.31.3
Electron affinity0.607 eV-0.5 eV
Density1.172000e+4 kg/m³1.400000e+4 kg/m³
Melting point1749.85 °C1049.85 °C
Boiling point4787.85 °C-273.15 °C
Discovery year18281949