Plutonium
Definition and meaning of Plutonium in chemistry.
![Plutonium element card: symbol Pu, atomic number 94, atomic mass [244], electron configuration [Rn] 5f⁶ 7s², oxidation states +4, Actinide, f-block, period 7, solid at room temperature.](/assets/images/terms/plutonium-chemical-element.webp)
Plutonium is a radioactive actinide metal with the chemical symbol Pu and atomic number 94. It is a heavy element that can take on six different crystal shapes. This complex metal also shows four distinct oxidation states when dissolved in water.
In more detail
Plutonium is a highly reactive, silvery-gray metal when it is first made. It quickly turns a dull, dark color when exposed to air. You can find tiny trace amounts of it naturally in uranium ores.
This happens when natural uranium atoms capture stray neutrons. However, scientists make almost all plutonium artificially inside nuclear reactors. They do this by hitting uranium-238 with a flow of neutrons.
The solid metal has a low melting point and a very high density. Unlike most things, plutonium actually expands as it melts into a liquid. It sits in the f-block of the periodic table with other heavy radioactive elements.
Its complex electron layout causes strange behavior and unpredictable chemical bonds. It often forms compounds that lack fixed atomic ratios. The metal goes through extreme physical changes under normal temperature swings.
Metal workers must mix plutonium with the element gallium. This mixture stabilizes the metal's structure at room temperature. This vital step lets workers safely shape the metal into strong parts.
Without the gallium, pure plutonium parts would become brittle. They would simply shatter during the manufacturing process.
Key facts
| Field | General Chemistry |
|---|---|
| Symbol | Pu |
| Atomic number | 94 |
| Atomic mass | [244] u |
| Category | Actinide |
| Year discovered | 1940 |
Plutonium-239 is a specific radioactive isotope. An isotope is a version of an element with a specific number of neutrons. This form easily keeps a nuclear chain reaction going. Military engineers use this powerful material as the explosive core in modern nuclear weapons. Scientists also use it as fuel in specialized nuclear reactors. This helps generate massive amounts of electricity.
Frequently asked questions
Is plutonium naturally occurring?
You can find plutonium naturally in extremely tiny amounts. These traces sit deep inside natural uranium ores. They form when natural uranium atoms capture stray neutrons.
Why is plutonium considered highly dangerous?
Plutonium gives off intense alpha radiation that harms nearby living tissue. The metal itself is also highly toxic to the human body. These traits pose severe health risks if a person breathes in or swallows the material.
Related terms
Sources & references
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