Np
93actinideGenerated with AI1 min read
Neptunium
SymbolNp
Atomic Mass237
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.
Properties
- Phase: Solid
- Density: 20.45 g/cm³
- Melting Point: 912 K
- Boiling Point: 4447 K