Element overview
Neptunium (Np) is element 93 with a listed atomic mass of 237 u. Its group is not assigned and period 7. Its category is actinide.
Atomic properties
Electron configuration: not listed. Electronegativity: not established. Common oxidation states: not listed.
Physical properties
Density: not listed; melting point: not listed; boiling point: not listed. Values depend on conditions, phase and source.