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Neptunium (Np)
Atomic number: 93 · Category: actinide · Group 3 · Period 7 · Phase: Solid
Neptunium is a chemical element with symbol Np and atomic number 93. A radioactive actinide metal, neptunium is the first transuranic element. Its position in the periodic table just after uranium, named after the planet Uranus, led to it being named after Neptune, the next planet beyond Uranus.
Atomic mass: 237
Density: 20.45
Melting point: 912 K
Boiling point: 4447 K
Appearance: silvery metallic
Source: Wikipedia
Block: f
Molar heat: 29.46
CPK color:#0080ff
Electronic structure
Electron configuration: 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f4 6d1
Configuration (semantic): [Rn] 5f4 6d1 7s2
Shells: 2, 8, 18, 32, 22, 9, 2
Electronegativity (Pauling): 1.36
Electron affinity: 45.85
Ionization energies: 604.5
Periodic position
Group: 3
Period: 7
xpos: 7
ypos: 10
Spectral/Bohr images
Image
3D Model