Np
237.000Neptunium
Neptünyum
Neptunium is a radioactive actinide with atomic number 93 and the first transuranium element. It is known for neptunium-237, neptunium-239, plutonium-238 production and long-term nuclear waste research.
93
237 g/mol
[Rn] 5f⁴ 6d¹ 7s²
2 | 8 | 18 | 32 | 22 | 9 | 2
1.36
20.45 g/cm³
643.9 °C
3999.8 °C
Edwin McMillan & Philip Abelson
Neptunium was discovered in 1940 by Edwin McMillan and Philip Abelson at Berkeley by bombarding uranium with neutrons. It was named after Neptune, the planet after Uranus, following the naming pattern from uranium.
Neptunium-237
Half-life: About 2.14 x 10⁶ years. Long-lived isotope important in nuclear waste and Pu-238 production.Neptunium-239
Half-life: About 2.36 days. Beta-decays to plutonium-239 and was central to early transuranium work.NpO₂
Neptunium(IV) OxideNuclear research and neptunium target material context.NpF₆
Neptunium HexafluorideVolatile actinide fluoride used in separation chemistry research.NpO₂⁺
Neptunyl(V) IonImportant aqueous species in neptunium environmental chemistry.- Neptunium-237 targets for producing plutonium-238 used in radioisotope power systems
- Long-term nuclear waste behavior and transmutation research
- Neutron detection and nuclear data studies
- Fundamental actinide chemistry across multiple oxidation states
Neptunium has no biological role. Its isotopes are radioactive and require strict radiological controls, especially in nuclear waste and actinide handling contexts.
- Neptunium was the first element beyond uranium to be synthesized and identified.
- Np-237 can be separated from spent nuclear fuel and is a key long-lived actinide in waste studies.
- Pu-238 production for spacecraft power begins with neutron irradiation of Np-237 targets.
- Neptunium has atomic number 93 and symbol Np.
- Its electron configuration is [Rn] 5f⁴ 6d¹ 7s².
- Neptunium is the first transuranium element.
- Remember Np-237 for Pu-238 production and long-term nuclear waste research.
What is the atomic number of neptunium?
The atomic number of neptunium is 93.
What is the electron configuration of neptunium?
Neptunium has the electron configuration [Rn] 5f⁴ 6d¹ 7s².
What is neptunium used for?
Neptunium is used mainly in nuclear research, especially Pu-238 production, waste studies and actinide chemistry.
What is neptunium-237?
Neptunium-237 is a long-lived isotope with a half-life of about 2.14 million years.
Why is neptunium important for space power?
Neptunium-237 can be irradiated to produce plutonium-238, the heat source isotope used in many space radioisotope power systems.