Polonium
Definition and meaning of Polonium in chemistry.
![Polonium element card: symbol Po, atomic number 84, atomic mass [209], electron configuration [Xe] 4f¹⁴ 5d¹⁰ 6s² 6p⁴, oxidation states +4 +2 -2, Metalloid, group 16, period 6, solid at room temperature.](/assets/images/terms/polonium-chemical-element.webp)
Polonium is a highly radioactive and very rare metalloid with the symbol Po and atomic number 84. It is an extremely dangerous element that gives off intense alpha radiation. The metal also releases a lot of heat as it naturally breaks down.
In more detail
Polonium sits in group 16 of the periodic table, directly below the element tellurium. Its chemical traits are very similar to both tellurium and bismuth. You can find tiny amounts of it in natural uranium ores, where it forms during radioactive decay.
Every isotope of polonium is radioactive and will quickly break down into other elements. Polonium-210 is the most common isotope and has a half-life of exactly 138 days. This short half-life means it decays rapidly, which produces a large amount of heat energy.
Students often think alpha radiation can penetrate human skin, but it is actually blocked by a single sheet of paper. However, polonium is incredibly dangerous if you swallow it or breathe it in. The alpha particles deposit all their energy directly into sensitive internal cells and destroy nearby DNA.
This internal exposure leads to severe organ failure and rapid death. Because it is so dangerous, polonium has very few commercial uses today.
Key facts
| Field | General Chemistry |
|---|---|
| Symbol | Po |
| Atomic number | 84 |
| Atomic mass | [209] u |
| Category | Metalloid |
| Year discovered | 1898 |
Workers sometimes use polonium-210 to remove static electricity in factories that produce delicate plastic films. They install the isotope inside brushes to neutralize static charges before dust can ruin the product. Engineers also use the element to power deep space probes that travel far from the Sun. Special generators convert the heat of the radioactive decay directly into usable electrical energy.
Frequently asked questions
Why does polonium release so much heat as it decays?
The rapid decay of polonium-210 releases high-energy alpha particles at a very fast rate. This intense bombardment of particles generates a lot of thermal energy inside the material.
How did scientists discover the element polonium?
Marie and Pierre Curie discovered polonium in 1898 while studying radioactive uranium ore. They named the new element after Marie's home country of Poland.
Can you block polonium radiation with basic materials?
Yes, you can easily block alpha radiation with a thin sheet of paper or plastic. However, the radiation becomes deadly if the radioactive atoms get inside the body.
Related terms
Sources & references
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