Cerium vs Neptunium

PropertyCe CeriumNp Neptunium
Atomic number5893
SymbolCeNp
NameCeriumNeptunium
Categorylanthanideactinide
Standard Atomic Weight140.116 u237 u
Period67
GroupN/AN/A
Blockss
Phase at STPsolidsolid
Electron configuration[Xe]6s24f15d1[Rn]7s25f46d1
Oxidation states[1, 2, 3, 4][2, 3, 4, 5, 6, 7]
Electronegativity (Pauling)1.121.36
Electron affinity0.955 eV0.48 eV
Density6770 kg/m³2.025000e+4 kg/m³
Melting point797.85 °C643.85 °C
Boiling point3423.85 °C3901.85 °C
Discovery year18011940