94PuPlutonium244[Rn] 5f⁶ 7s²
actinide
Plutonium
Plutonium is a transuranic radioactive chemical element with symbol Pu and atomic number 94. It is an actinide metal of silvery-gray appearance that tarnishes when exposed to air, and forms a dull coating when oxidized. The element normally exhibits six allotropes and four oxidation states.
A stylized shell model. Electrons are quantum objects, not particles following these literal paths. Sizes and motion are illustrative.
Electrons by shell
Electron configuration
5f6
7s2
86 is the [Rn] core total across six shells.
At a glance
- Atomic number
- 94
- Atomic mass
- 244 u
- Phase
- Solid
- Density
- 19.816 g/cm³
- Melting point
- 912.5 K
- Boiling point
- 3,505 K
- First ionization energy
- 584.7 kJ/mol
- Electronegativity
- 1.28
- Electron affinity
- -48.33 kJ/mol
- Molar heat capacity
- 35.5 J/(mol·K)
- Period
- 7
- Appearance
- silvery white, tarnishing to dark gray in air
Conditions and isotopes affect measured properties. Some properties of short-lived elements are predicted. Electronegativity uses the Pauling scale.
Keep exploring
Explore the stories, imagery, and reference data in more depth. Properties with no value in the reference are marked unavailable.