Atomic Number: 93

Name: Neptunium

Atomic symbol: Np

Atomic Weight: 237.048

Electron configuration: 1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶4d¹⁰5s²5p⁶4f¹⁴5d¹⁰5f⁴6s²6p⁶6d¹7s²

Melting Point: 640^oC

Boiling Point: 3902^oC

Ionic radius: 1.10 angstroms (+3); 0.95 angstroms (+4); 0.71 angstroms (+7)