93Np
Element 93
Neptunium
Actinides
Neptunium is a chemical element with symbol Np and atomic number 93.
Key data
- Atomic number
- 93
- Atomic mass
- 237.000 u
- Group / Period
- 3 / 7
- Block
- f-block
- Phase at STP
- Solid
- Density
- 20.45 g/cm³
- Melting point
- 638.9 °C
- Boiling point
- 4173.9 °C
- Electron configuration
- [Rn] 5f4 6d1 7s2
Common uses
- •Neutron detectors
- •Research only
- •Radioactive
Discovery
Year: 1940
Discovered by: Edwin McMillan
Frequently asked questions
What is the atomic number of Neptunium?
Neptunium has atomic number 93. Its symbol is Np and its atomic mass is 237 u.
What category of element is Neptunium?
Neptunium is classified as actinides. It sits in group 3, period 7 of the periodic table.
What is Neptunium used for?
Common uses of Neptunium include: Neutron detectors, Research only, Radioactive.
When was Neptunium discovered?
Neptunium was discovered in 1940 by Edwin McMillan.
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