Cerium vs Berkelium

PropertyCe CeriumBk Berkelium
Atomic number5897
SymbolCeBk
NameCeriumBerkelium
Categorylanthanideactinide
Standard Atomic Weight140.116 u247 u
Period67
GroupN/AN/A
Blockss
Phase at STPsolidsolid
Electron configuration[Xe]6s24f15d1[Rn]7s25f9
Oxidation states[1, 2, 3, 4][2, 3, 4, 5]
Electronegativity (Pauling)1.121.3
Electron affinity0.955 eV-0.5 eV
Density6770 kg/m³1.400000e+4 kg/m³
Melting point797.85 °C1049.85 °C
Boiling point3423.85 °C-273.15 °C
Discovery year18011949