93 Np 237
Neptunium
actinide
Properties
- Atomic number
- 93
- Atomic mass
- 237 u
- Category
- actinide
- Group
- f-block
- Period
- 7
- Block
- f-block
- State (room temp)
- Solid
- Outer-shell electrons
- 2
- Electronegativity
- 1.36 (Pauling)
- Density
- 20.45 g/cm³
- Melting point
- 638.85 °C
- Boiling point
- 4173.85 °C
Electron configuration
1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s² 4d¹⁰ 5p⁶ 6s² 4f¹⁴ 5d¹⁰ 6p⁶ 7s² 5f⁴ 6d¹
Noble-gas shorthand: [Rn] 5f⁴ 6d¹ 7s²
Electrons per shell: 2, 8, 18, 32, 22, 9, 2, which is 2 in the outermost shell.
Related: electron configuration, the Bohr model, valence electrons.
About Neptunium
Neptunium is a chemical element with symbol Np and atomic number 93. A radioactive actinide metal, neptunium is the first transuranic element. Its position in the periodic table just after uranium, named after the planet Uranus, led to it being named after Neptune, the next planet beyond Uranus.
- Discovered by Edwin McMillan
- Appearance: silvery metallic
Neptunium: frequently asked questions
- What is Neptunium?
- Neptunium (Np) is the chemical element with atomic number 93. It is a metal: specifically an actinide.
- What is the atomic number of Neptunium?
- Neptunium's atomic number is 93, which means every Neptunium atom has 93 protons in its nucleus.
- What is the electron configuration of Neptunium?
- The electron configuration of Neptunium is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f4 6d1 (noble-gas shorthand: [Rn] 5f4 6d1 7s2). Its electrons are arranged in shells of 2, 8, 18, 32, 22, 9, 2, with 2 in the outermost shell.
- Is Neptunium a metal or a nonmetal?
- Neptunium is a metal: specifically an actinide.
- What group and period is Neptunium in?
- Neptunium sits in the f-block (the actinide row) of period 7 on the periodic table.
- Is Neptunium a solid, liquid, or gas?
- At room temperature, Neptunium is a solid.
Position in the periodic table
Data compiled from Wikipedia, PubChem, and IUPAC. Source.