 |
| Name |
neptunium |
| Symbol |
Np |
| Atomic Weight |
237.05 |
| Atomic Number |
93 |
| CAS ID |
7439-99-8 |
| Group Number |
|
| Group Name |
Actinoid |
| Period Number |
7 |
| Origin of Name |
Named after the planet Neptune. |
| Year Discovered |
1940 |
| Discovery Credits |
E. M. McMillan and P. Abelson at Berkeley, California, USA. |
| Class |
Metallic |
| Color |
Silvery Metallic |
| Standard State |
Solid at 77 F & 298 K |
| Description |
Radioactive silvery metal which does not occur naturally. Attacked by
oxygen, steam, and acids, but not alkalis. |
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