Is Radon a Metal or Nonmetal? (+ 3 Facts You Should Know)

Radon is a nonmetal and belongs to the noble gas group on the periodic table. Unlike metals, which are typically solid at room temperature, radon is a colorless, odorless gas that is radioactive and highly toxic. ¹

Well, this was just a simple answer. But there are few more things to know about this topic which will make your concept super clear.

So let’s dive right into it.

Why is radon a nonmetal?

Radon is a nonmetal because it lacks many of the physical and chemical properties that are commonly associated with metals.

Metals are typically shiny, malleable, ductile, and good conductors of heat and electricity. ² Radon, on the other hand, is a gas at room temperature and pressure, and it is not malleable or ductile. It is also not a good conductor of heat or electricity.

Furthermore, radon belongs to the group of elements known as noble gases, which are characterized by their low reactivity with other elements. This means that radon does not readily form chemical bonds with other elements, which is a key characteristic of nonmetals. ³

In summary, radon is classified as a nonmetal due to its lack of metallic properties and its low reactivity with other elements.

Properties of radon that classify it as a nonmetal

There are several properties of radon that classify it as a nonmetal:

• Physical state: Radon is a gas at room temperature and pressure, which is a common characteristic of nonmetals. Unlike metals that are typically solids at room temperature, radon does not have a definite shape or volume.
• Lack of metallic luster: Metals are generally shiny and reflective, but radon lacks this property. It is a colorless and odorless gas that is not reflective. ⁴
• Poor conductor of heat and electricity: Metals are excellent conductors of heat and electricity due to the movement of free electrons in their structure. In contrast, radon is a poor conductor of heat and electricity, which is a typical property of nonmetals.
• Low boiling and melting points: Nonmetals generally have low boiling and melting points. Radon has a boiling point of -61.7°C and a melting point of -71.0°C, which are both very low. ⁵
• Low reactivity: Nonmetals have low reactivity and do not readily form chemical bonds with other elements. Radon belongs to the group of noble gases, which are highly unreactive elements. This means that radon does not easily react with other elements to form compounds.

Overall, these properties of radon are characteristic of nonmetals, which is why it is classified as one.

How is radon different from other nonmetals?

Radon is different from other nonmetals in a few ways:

• Radioactivity: Radon is the only naturally occurring radioactive nonmetal. This means that its atomic nucleus is unstable and can undergo spontaneous radioactive decay, emitting alpha, beta, and gamma particles. ^{6 7}
• Density: Radon is much denser than the other nonmetals, such as nitrogen, oxygen, and fluorine. This is because radon is a noble gas with a full outer electron shell, making it more difficult to compress and reducing its volume. ⁸
• Occurrence: Radon is a rare element that occurs naturally in small amounts in the Earth’s crust. It is formed by the radioactive decay of uranium and thorium, which are more common in the Earth’s crust than radon.
• Toxicity: Unlike most other nonmetals, radon is highly toxic and can cause lung cancer when inhaled in high concentrations. This is due to the radioactive decay products that are released when radon breaks down in the lungs. ^{9 10}

Overall, radon has unique properties that differentiate it from other nonmetals, including its radioactivity, high density, rare occurrence, and toxicity.

Further reading

Is Chlorine Solid, Liquid or Gas?
Is Sulfur a Solid, Liquid or Gas?
Is Carbon Solid, Liquid or Gas?
Is Boron a Solid, Liquid or Gas?
Is Hydrogen a Solid, Liquid or Gas? 

About author

Jay Rana

Jay is an educator and has helped more than 100,000 students in their studies by providing simple and easy explanations on different science-related topics. He is a founder of Pediabay and is passionate about helping students through his easily digestible explanations.

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