Neptunium

Symbol

Np

Atomic number

93

Atomic mass	237.048		Thermal conductivity	0.063
Atomic radius	...		Covalent radius	...
Density	20.4		Atomic volume	11.62
Melting point	913		Oxidation states	6,5,4,3
Boiling point	4175		Stable isotopes	...
Heat of vapor.	...		Electronegativity	1.36
Heat of fusion	5.19		First ionization	6.19
Specific heat	0.12		Electrical conduct.	...

Electron configuration

Neptunium

Neptunium was first made in 1940 by E M McMilland and P H Abelson of the University of California. Bombarding U238 with neutrons to form U239 leads to beta decay to form Np239. Neptunium is important as an intermediate product in the manufacture of plutonium.

Neptunium Nuclear Data