Plutonium (Pu): Electron Configuration, Properties and Uses
Plutonium (Pu): Electron Configuration, Properties and Uses
Electron configuration [Rn] 7s2 5f6 · f-block, actinide series · period 7 · Ar [244]
Plutonium data
- Atomic number
- 94
- Relative atomic mass
- [244]
- Group
- – (actinide series)
- Period
- 7
- Block
- f
- Category
- Actinide
- Electron configuration
- [Rn] 7s2 5f6
- Full configuration
- 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f6
- Electrons per shell
- 2, 8, 18, 32, 24, 8, 2 (K L M N O P Q)
- Valence electrons
- 2 (in the outer shell)
- Electronegativity (Pauling)
- 1.28
- First ionisation energy
- 6.06 eV
- Atomic radius (van der Waals)
- 243 pm
- State at room temperature
- Solid
- Melting point
- 640 °C
- Boiling point
- 3228 °C
- Density
- 19.84 g/cm³
- Common oxidation states
- +6, +5, +4, +3
- Discovered
- 1940
Source: PubChem (NIH, accessed 13 Nov 2026); atomic mass: IUPAC standard atomic weight.
Electron shell diagram
K 2 · L 8 · M 18 · N 32 · O 24 · P 8 · Q 2
Orbital diagram (outer electrons)
About plutonium
With atomic number 94, plutonium (Pu) has 94 protons in its nucleus and 94 electrons as a neutral atom. It belongs to the actinide series in period 7 (f-block), usually shown below the main table. Plutonium was first discovered in 1940. It is named after Pluto. Plutonium is a solid at room temperature, melting at 640 °C and boiling at 3228 °C.
Plutonium electron configuration
The electron configuration of plutonium is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f6, or in short [Rn] 7s2 5f6. Its electrons occupy 7 shells: K = 2, L = 8, M = 18, N = 32, O = 24, P = 8, Q = 2. As an actinide, plutonium fills the 5f subshell. Its outer 7s subshell holds 2 electrons; valence electrons for this series are not assigned by the usual group rule. When it forms cations, electrons leave the outermost subshell first: Pu3+ = [Rn] 5f5.
Filling order: 1s2(2) → 2s2(4) → 2p6(10) → 3s2(12) → 3p6(18) → 4s2(20) → 3d10(30) → 4p6(36) → 5s2(38) → 4d10(48) → 5p6(54) → 6s2(56) → 4f14(70) → 5d10(80) → 6p6(86) → 7s2(88) → 5f6(94)
Uses of plutonium
In industry and the laboratory, plutonium turns up in many places, for example MOX nuclear fuel and radioisotope power (Pu-238) for spacecraft such as Voyager and the Mars rovers.
Safety
Plutonium is radioactive. Using, storing or transporting radioactive material requires a licence from the national regulator (BAPETEN in Indonesia). Always read the safety data sheet (SDS) before working with a chemical.
Other actinides
Frequently asked questions
What is the electron configuration of plutonium?
The electron configuration of plutonium (Pu, atomic number 94) is 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s2 4d10 5p6 6s2 4f14 5d10 6p6 7s2 5f6, or [Rn] 7s2 5f6 in short. By shell: 2, 8, 18, 32, 24, 8, 2.
How many valence electrons does plutonium have?
Plutonium has 2 electrons in its outer shell. For lanthanides and actinides, valence electrons are not assigned by the usual group rule.
Which group and period is plutonium in?
Plutonium is in the actinide series, period 7, f-block.
What is the atomic mass of plutonium?
Plutonium has no stable isotope, so the mass number of its longest-lived isotope, [244], is given.
Prepare solutions with analytical-grade reagents
AMI Scientific is one of the official TCI distributors in Indonesia. Reagents with lot CoA & SDS, formal quotations and tax invoices for universities and laboratories.
Other formulas & calculators: molarity, mole, molality, normality, dilution, titration, pH, buffer, molar mass, ppm, mole fraction, mass percent, periodic table, chemical MSDS.
