Samarium vs Berkelium

PropertySm SamariumBk Berkelium
Atomic number6297
SymbolSmBk
NameSamariumBerkelium
Categorylanthanideactinide
Standard Atomic Weight150.36 u247 u
Period67
GroupN/AN/A
Blockss
Phase at STPsolidsolid
Electron configuration[Xe]6s24f6[Rn]7s25f9
Oxidation states[0, 1, 2, 3][2, 3, 4, 5]
Electronegativity (Pauling)1.171.3
Electron affinity0.156 eV-0.5 eV
Density7520 kg/m³1.400000e+4 kg/m³
Melting point1073.85 °C1049.85 °C
Boiling point1793.85 °C-273.15 °C
Discovery year18781949