Is Arsenic a Metal, Nonmetal or Metalloid? (And Why?)

Arsenic is a metalloid. Metalloids are elements that have properties of both metals and nonmetals, and they are located along the zigzag line on the periodic table. 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 arsenic a metalloid?

Arsenic is classified as a metalloid because it has properties of both metals and nonmetals.

On the one hand, arsenic is a solid at room temperature, has metallic luster, and is a good conductor of electricity, which are typical characteristics of metals. ²

On the other hand, arsenic is not malleable or ductile, is brittle and can be easily broken, and has some chemical properties of nonmetals, such as being able to form covalent bonds. ³

Furthermore, the position of arsenic on the periodic table is also a reason for its classification as a metalloid.

Arsenic is located in the p-block of the periodic table, which is a group of elements that includes both metals and nonmetals. ⁴ In the same group, elements such as nitrogen, phosphorus, and antimony are also classified as metalloids due to their similar properties.

In summary, arsenic is classified as a metalloid because it exhibits both metallic and nonmetallic properties and is located in a group of elements that includes both metals and nonmetals.

Properties of arsenic that classify it as a metalloid

There are several properties of arsenic that classify it as a metalloid. Here are some of them:

• Physical appearance: Arsenic has a metallic luster, and it is a solid at room temperature. This is a typical characteristic of metals.
• Electrical conductivity: Arsenic can conduct electricity, which is another property commonly associated with metals.
• Brittle: Arsenic is not malleable or ductile and is brittle, meaning it can be easily broken. This is a property more commonly found in nonmetals. ⁵
• Chemical behavior: Arsenic exhibits some chemical properties of nonmetals, such as forming covalent bonds with other elements. ⁶
• Position on the periodic table: Arsenic is located in the p-block of the periodic table, which is a group of elements that includes both metals and nonmetals.
• Oxidation states: Arsenic can form both positive and negative oxidation states, which is a property shared by both metals and nonmetals. ^{7 8 9}

In summary, the properties of arsenic that classify it as a metalloid include its physical appearance, electrical conductivity, brittleness, chemical behavior, position on the periodic table, and oxidation states.

How is arsenic different from other metalloids?

Arsenic is different from other metalloids in several ways. Here are some of them:

• Toxicity: Arsenic is highly toxic to humans and animals, whereas other metalloids such as silicon and germanium are not.
• Density: Arsenic has a higher density than other metalloids such as silicon and boron.
• Allotropes: Arsenic has several allotropes (different forms of the same element), whereas other metalloids have fewer allotropes or only one. ¹⁰
• Semiconducting properties: Arsenic has semiconducting properties, which make it useful in electronics and computer industries. Other metalloids such as antimony and bismuth have different semiconducting properties or are not semiconductors at all.
• Abundance: Arsenic is more abundant in the Earth’s crust than other metalloids, except for silicon. ¹¹

In summary, arsenic differs from other metalloids in terms of its toxicity, density, allotropes, semiconducting properties, and abundance.

Further reading

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

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