Potassium vs Californium

PropertyK PotassiumCf Californium
Atomic number1998
SymbolKCf
NamePotassiumCalifornium
Categoryalkali-metalactinide
Standard Atomic Weight39.0983 u251 u
Period47
Group1N/A
Blockss
Phase at STPsolidsolid
Electron configuration[Ar]4s1[Rn]7s25f10
Oxidation states[-1, 1][2, 3, 4, 5]
Electronegativity (Pauling)0.821.3
Electron affinity0.5014 eV-0.5 eV
Density890 kg/m³1.510000e+4 kg/m³
Melting point63.38 °C899.85 °C
Boiling point758.85 °C-273.15 °C
Discovery year18071950