Chromium vs Neptunium

PropertyCr ChromiumNp Neptunium
Atomic number2493
SymbolCrNp
NameChromiumNeptunium
Categorytransition-metalactinide
Standard Atomic Weight51.9961 u237 u
Period47
Group6N/A
Blockss
Phase at STPsolidsolid
Electron configuration[Ar]3d54s1[Rn]7s25f46d1
Oxidation states[-4, -2, -1, 0, 1, 2, 3, 4, 5, 6][2, 3, 4, 5, 6, 7]
Electronegativity (Pauling)1.661.36
Electron affinity0.675 eV0.48 eV
Density7150 kg/m³2.025000e+4 kg/m³
Melting point1906.85 °C643.85 °C
Boiling point2670.85 °C3901.85 °C
Discovery year17971940