Element: neptunium |
Name : neptunium |
Symbol : Np |
Atomicnumber : 93 |
Relativeatomicmass : [ 237 ] (longest lived isotope) |
Standardstate : solid at 298 K |
Appearance : silvery metallic |
Classification : Metallic |
Groupinperiodictable : None |
Groupname : Actinoid |
Periodinperiodictable : 7 (actinoid) |
Blockinperiodictable : f |
Shellstructure : 2.8.18.32.22.9.2 |
CASRegistry : 7439-99-8 |
Description : Neptunium is a radioactive rare earth metal and has at least 3 allotropic forms. It is named for the planet Neptune. |