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93 - Neptunium actinide

Discovered by Edwin McMillan in 1940

Neptunium

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.
Shell Electrons Orbitals
1 2 2 in 1s
2 8 2 in 2s + 6 in 2p
3 18 2 in 3s + 6 in 3p + 10 in 3d
4 32 2 in 4s + 6 in 4p + 10 in 4d + 14 in 4f
5 22 2 in 5s + 6 in 5p + 10 in 5d + 4 in 5f
6 9 2 in 6s + 6 in 6p + 1 in 6d
7 2 2 in 7s
NeptuniumNp Electron 1 Electron 2 Electron 1 Electron 2 Electron 3 Electron 4 Electron 5 Electron 6 Electron 7 Electron 8 Electron 1 Electron 2 Electron 3 Electron 4 Electron 5 Electron 6 Electron 7 Electron 8 Electron 9 Electron 10 Electron 11 Electron 12 Electron 13 Electron 14 Electron 15 Electron 16 Electron 17 Electron 18 Electron 1 Electron 2 Electron 3 Electron 4 Electron 5 Electron 6 Electron 7 Electron 8 Electron 9 Electron 10 Electron 11 Electron 12 Electron 13 Electron 14 Electron 15 Electron 16 Electron 17 Electron 18 Electron 19 Electron 20 Electron 21 Electron 22 Electron 23 Electron 24 Electron 25 Electron 26 Electron 27 Electron 28 Electron 29 Electron 30 Electron 31 Electron 32 Electron 1 Electron 2 Electron 3 Electron 4 Electron 5 Electron 6 Electron 7 Electron 8 Electron 9 Electron 10 Electron 11 Electron 12 Electron 13 Electron 14 Electron 15 Electron 16 Electron 17 Electron 18 Electron 19 Electron 20 Electron 21 Electron 22 Electron 1 Electron 2 Electron 3 Electron 4 Electron 5 Electron 6 Electron 7 Electron 8 Electron 9 Electron 1 Electron 2
237  u Atomic Mass
4273  K Boiling Point
1.9  Å Covalent Radius
20.45  g/cm³ Density
45.85 Electron Affinity
1.36 Electronegativity
6.27  eV First Ionization Energy
913.15  K Melting Point
7 Number of Shells
93 Atomic Number