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Metalloid

physical science Maturity 9-11 Next article →

Some elements are very hard to group. Most elements are either metals or nonmetals, but metalloids sit right in the middle.

The name comes from Latin and Greek words meaning "resembling metal" in appearance. Because they share traits from both groups, they are difficult to classify. Scientists often find it hard to agree on a single definition. This makes the study of metalloids a very interesting puzzle.

Boron R105
Boron R105

How do these elements work? They often have a metallic look, but they can be brittle and break easily.

Arsen 1a
Arsen 1a

They are also fair conductors of electricity. This means they let power flow, but not as well as true metals do. Many metalloids are semiconductors. A semiconductor is a material that can control how electricity moves through it.

They can even form alloys, which are mixtures of different metals.

The history of this word has changed over time. Originally, the term metalloid was used to describe nonmetals. However, its modern meaning became common between 1940 and 1960. This newer meaning describes elements with hybrid or middle-ground properties. Some people used to call them semimetals. Today, scientists discourage that name because it means something else in physics. In physics, only arsenic and antimony are called semimetals.

Antimony-4
Antimony-4

There are several key elements to know. Six elements are commonly recognized as metalloids: boron, silicon, germanium, arsenic, antimony, and tellurium.

Tellurium2
Tellurium2

Other scientists sometimes add elements like carbon, aluminium, selenium, polonium, or astatine to the list. On a periodic table, these eleven elements form a diagonal path. This path goes from boron at the top left to astatine at the bottom right.

Polycrystalline-germanium
Polycrystalline-germanium

This diagonal shape is an exception to how other elements are grouped.

We use metalloids in many parts of our daily lives. They are vital for making electronics and semiconductors.

Blue Light
Blue Light

They are also used in optical storage and special glasses. Some metalloids help make flame retardants or are used in pyrotechnics. You might even find them in biological agents or catalysts. Even the fiber optic cables that carry data use these special properties.

Fibreoptic4
Fibreoptic4

They help connect our modern world in many ways.

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🖼️ Images & Media (14)
File:Copper germanium.jpg
Copper germanium.jpg
File:Arsenic trioxide.jpg
Arsenic trioxide.jpg
File:Fibreoptic4.jpg
Fibreoptic4.jpg
File:Blue Light.JPG
Blue Light.JPG
File:Boron R105.jpg
Boron R105.jpg
File:Polycrystalline-germanium.jpg
Polycrystalline-germanium.jpg
File:Arsen 1a.jpg
Arsen 1a.jpg
File:Antimony-4.jpg
Antimony-4.jpg
File:Tellurium2.jpg
Tellurium2.jpg
File:Graphite2.jpg
Graphite2.jpg
File:Aluminium-4.jpg
Aluminium-4.jpg
File:Selenium black (cropped).jpg
Selenium black (cropped).jpg

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