Ytterbium vs Neptunium

PropertyYb YtterbiumNp Neptunium
Atomic number7093
SymbolYbNp
NameYtterbiumNeptunium
Categorylanthanideactinide
Standard Atomic Weight173.054 u237 u
Period67
GroupN/AN/A
Blockss
Phase at STPsolidsolid
Electron configuration[Xe]6s24f14[Rn]7s25f46d1
Oxidation states[0, 1, 2, 3][2, 3, 4, 5, 6, 7]
Electronegativity (Pauling)N/A1.36
Electron affinity-0.02 eV0.48 eV
Density6900 kg/m³2.025000e+4 kg/m³
Melting point818.85 °C643.85 °C
Boiling point1195.85 °C3901.85 °C
Discovery year18781940