Neptunium (Np)
Neptunium (Np, element 93) is an actinide in period 7. Atomic mass 237, electron configuration [Rn] 5f⁴ 6d¹ 7s², uses and facts.
About Neptunium
Neptunium is an actinide with the symbol Np and atomic number 93. It is a solid at room temperature, and it sits in period 7 of the periodic table. Neptunium was discovered in 1940 by Edwin McMillan.
Neptunium key facts
- Atomic number: 93
- Symbol: Np
- Atomic mass: 237 u
- Category: actinide
- Group: none (f-block)
- Period: 7
- State at room temperature: solid
- Electron configuration: [Rn] 5f⁴ 6d¹ 7s²
- Electronegativity (Pauling): 1.36
- Melting point: 917 K (643.85 °C)
- Boiling point: 4273 K (3999.85 °C)
- Density: 20.45 g/cm³
- Common oxidation states: +2, +3, +4, +5, +6, +7
Electron configuration
The electron configuration of neptunium is [Rn] 5f⁴ 6d¹ 7s². The part in brackets is the noble gas core; the rest shows how the outer electrons fill their subshells.
Uses of neptunium
- Neutron detection
- Research
Did you know?
Neptunium was the first transuranium element discovered, named after Neptune, the next planet after Uranus.
Neighbouring elements
- Uranium (U)
- Plutonium (Pu)
- Actinium (Ac)
- Thorium (Th)
- Protactinium (Pa)
- Uranium (U)
- Plutonium (Pu)
- Americium (Am)
- Curium (Cm)
- Berkelium (Bk)
Frequently asked questions
What is the atomic number of neptunium?
The atomic number of neptunium is 93, which means every neptunium atom has 93 protons.
What is the electron configuration of neptunium?
The electron configuration of neptunium is [Rn] 5f⁴ 6d¹ 7s².
What group and period is neptunium in?
Neptunium is an actinide in period 7.
What state is neptunium at room temperature?
Neptunium is a solid at room temperature.
What is neptunium used for?
Neptunium is used for neutron detection, research.