Californium vs Einsteinium

PropertyCf CaliforniumEs Einsteinium
Atomic number9899
SymbolCfEs
NameCaliforniumEinsteinium
Categoryactinideactinide
Standard Atomic Weight251 u252 u
Period77
GroupN/AN/A
Blockss
Phase at STPsolidsolid
Electron configuration[Rn]7s25f10[Rn]7s25f11
Oxidation states[2, 3, 4, 5][2, 3, 4]
Electronegativity (Pauling)1.31.3
Electron affinity-0.5 eV-0.3 eV
Density1.510000e+4 kg/m³8840 kg/m³
Melting point899.85 °C859.85 °C
Boiling point-273.15 °C-273.15 °C
Discovery year19501952