Potassium vs Rutherfordium

PropertyK PotassiumRf Rutherfordium
Atomic number19104
SymbolKRf
NamePotassiumRutherfordium
Categoryalkali-metaltransition-metal
Standard Atomic Weight39.0983 u263 u
Period47
Group14
Blockss
Phase at STPsolidsolid
Electron configuration[Ar]4s1[Rn]7s25f146d2
Oxidation states[-1, 1][3, 4]
Electronegativity (Pauling)0.82N/A
Electron affinity0.5014 eV0.65 eV
Density890 kg/m³2.330000e+4 kg/m³
Melting point63.38 °C2126.85 °C
Boiling point758.85 °C5526.85 °C
Discovery year18071964