Berkelium vs Californium

Side-by-side comparison of Berkelium (Bk, element 97) and Californium (Cf, element 98) by atomic structure and physical properties.

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PropertyBk Berkelium Cf Californium
Atomic number9798
SymbolBkCf
NameBerkeliumCalifornium
Categoryactinideactinide
Standard Atomic Weight247 u251 u
Period77
GroupN/AN/A
Blockff
Phase at STPSolidSolid
Electron configuration[Rn]5f97s2[Rn]5f107s2
Oxidation states[2, 3, 4, 5][2, 3, 4, 5]
Electronegativity (Pauling)1.31.3
Electron affinity-1.72 eV-1.01 eV
Density1.478e+4 kg/m³1.51e+4 kg/m³
Melting point1049.85 °C899.85 °C
Boiling pointN/AN/A
Discovery year19491950

Key Differences

PropertyBk BerkeliumCf Californium
Standard Atomic Weight247 u ↓ lower251 u ↑ higher
Density1.478e+4 kg/m³ ↓ lower1.51e+4 kg/m³ ↑ higher
Melting point1049.85 °C ↑ higher899.85 °C ↓ lower
Electron affinity-1.72 eV ↓ lower-1.01 eV ↑ higher
Electron configuration[Rn]5f97s2 [Rn]5f107s2
Discovery year1949 1950