Plutonium
A dense radioactive metal powering weapons and spacecraft.
Inside the Plutonium atom
Switch between Bohr and Quantum Cloud modes to compare a simple teaching model with a more realistic probability-based view, and follow the guided tour to explore the Plutonium atom step by step.
Electron configuration
[Rn] 5f6 7s2
A neutral Plutonium atom has 94 electrons (equal to its proton count). Choosing a different isotope above changes only the neutron count.
Shell distribution
Electrons fill inner shells before outer ones; the outermost (valence) shell drives the element's chemistry.
Physical & atomic properties
- State (room temp)
- Solid
- Melting point
- 913 K (639 °C)
- Boiling point
- 3501 K (3228 °C)
- Density
- 19.84 g/cm³
- Electronegativity
- 1.28 Pauling
- Atomic radius
- 175 pm
- 1st ionization energy
- 585 kJ/mol
- Category
- Actinides
Discovery & naming
- Discovered
- 1940
- Discovered by
- Glenn Seaborg and colleagues
- Origin of name
- The dwarf planet Pluto.
Notable uses
Nuclear weapons and long-lived spacecraft power.
Where Plutonium comes from
Human synthesis
Minute natural traces exist in uranium ores, but effectively all plutonium on Earth was made in reactors.
Simplified origin map — many elements form through more than one astrophysical pathway.
Summary
- Atomic number
- 94
- Atomic mass
- [244]
- Category
- Actinides
- Group · Period
- — · 7
- Block
- f-block
- Shells
- 2 · 8 · 18 · 32 · 24 · 8 · 2