Gallium Facts for Kids

Shiny crystals of gallium joined together

Gallium (chemical symbol: Ga) is a chemical element. It is number 31 on the periodic table.

Gallium is a metal, but it has some very special features. If you hold it in your hand, it will melt! This is because it has a very low melting point. Gallium does not let electricity pass through it easily. This makes it a semiconductor. Semiconductors are important in computers and other electronics. Gallium is also very shiny. When melted, it can be used to make bright mirrors.

Very pure gallium looks like shiny silver. When it is solid, it breaks easily, almost like glass. Gallium metal gets bigger by about 3.1 percent when it turns from liquid to solid. Because of this, you should not store it in glass or metal containers. Gallium can also slowly damage most other metals by mixing into them.

History of Gallium
How Gallium is Used
Where Gallium is Found
Safety with Gallium
Images for kids
See also

History of Gallium

Gallium was found using a special method called spectroscopy. This happened in 1875. The scientist who discovered it was Paul-Émile Lecoq de Boisbaudran.

Before it was even found, a famous scientist named Dmitri Mendeleev had already guessed many of its properties. He called this unknown element eka-aluminium. He predicted it based on its place in his periodic table.

Later in 1875, Boisbaudran got the pure metal. He used a process called electrolysis on a gallium compound. He named the element after his home country, France. The Latin word for France is Gallia. He also made a clever joke with the name. His own name, 'Lecoq', means 'the rooster' in French. The Latin word for rooster is gallus.

How Gallium is Used

Blue LED lights often use gallium

Galinstan, a gallium alloy, wetting a piece of glass

Gallium is used a lot in electronic parts called integrated circuits. These are like tiny brains for computers. It is also used in devices that make light. These include laser diodes and LED lights.

Here are some other ways gallium is used:

It can stick to glass or porcelain. This makes it useful for creating very shiny mirrors.
Gallium helps make semiconductors work better. It is used in parts like transistors.
Some special thermometers that measure very high temperatures use gallium.
Gallium mixes easily with most metals. It is used to make special metal mixes (alloys) that melt at low temperatures.
A liquid mix of Gallium and Tin could be used to cool computer chips. It is much better at cooling than water.
Some gallium compounds are used in hospitals. They help doctors see inside the body with special medical scans.

Where Gallium is Found

You won't find pure gallium by itself in nature. It is always mixed with other things. Gallium is found in minerals and ores deep in the Earth's crust. Some dust from burning coal has even been found to contain a small amount of gallium.

Safety with Gallium

Gallium is not usually thought of as harmful. However, we don't have all the information about its safety. Some people think that touching it for a long time might cause a skin rash called dermatitis. Other tests have not shown this problem.