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

Selenium is a nonmetal. It shares many properties with other nonmetals, such as having low melting and boiling points, and forming covalent bonds with other elements. 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.

Explanation: Why is selenium a nonmetal?

Selenium is classified as a nonmetal because it lacks the characteristics of a metal.

Metals generally have a shiny appearance, are good conductors of electricity and heat, and are malleable and ductile.

Selenium, on the other hand, is a nonmetal that has a dull appearance and is brittle. ²

Additionally, nonmetals generally have higher electronegativity values than metals.

Electronegativity is the measure of an atom’s ability to attract electrons towards itself in a covalent bond. Selenium has a relatively high electronegativity value, which is another characteristic that supports its classification as a nonmetal. ³

Therefore, based on its physical and chemical properties, selenium is classified as a nonmetal.

Properties of selenium that classify it as a nonmetal

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

• Dull appearance: Selenium is a nonmetal that has a dull or grayish appearance. This is in contrast to metals, which are generally shiny. ⁴
• Brittle: Selenium is a brittle material, meaning that it is easily broken or cracked. This is due to the way that the atoms are arranged in the material, which does not allow for easy deformation.
• High electronegativity: Electronegativity is a measure of an atom’s ability to attract electrons towards itself in a covalent bond. Nonmetals generally have higher electronegativity values than metals, and selenium is no exception. Its relatively high electronegativity value is another characteristic that supports its classification as a nonmetal.

Overall, these properties demonstrate that selenium does not exhibit the typical characteristics of metals, and is therefore classified as a nonmetal.

How is selenium different from other nonmetals?

Selenium differs from other nonmetals in several ways, including:

• Physical appearance: While many nonmetals are gases at room temperature, selenium is a solid. Additionally, selenium has a distinctive grayish or metallic appearance that sets it apart from other nonmetals.
• Applications: Selenium has unique properties that make it useful in a variety of applications, including electronics, glassmaking, and photography. In contrast, many other nonmetals are primarily used for their chemical reactivity. ^{5 6}
• Toxicity: Selenium is one of the few nonmetals that is toxic in large doses. While some other nonmetals can be harmful in certain forms (such as inhalation of sulfur dioxide), selenium is unique in its potential for toxicity. ^{7 8}
• Chemical properties: Selenium has some chemical properties that are distinct from other nonmetals. For example, it can form both acidic and basic oxides, and it exhibits photoconductivity (meaning that its electrical conductivity can change in response to light). ^{9 10 11}

These differences highlight the unique properties and applications of selenium within the category of nonmetals.

Further reading

Is Bromine a Metal or Nonmetal?
Why is Krypton a Noble Gas?
Is Krypton a Metal or Nonmetal?
Is Rubidium a Metal?
Is Strontium a Metal or Nonmetal? 

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