What is Gallium?
Gallium is the third element in the thirteenth column of the periodic table. It is classified as a post-transition metal or an “other” metal. The gallium atom has 31 electrons and 31 protons with 3 valence electrons in the outermost shell.
Characteristics and Properties
Under normal conditions gallium is a soft, silvery metal. It is very fragile and will break easily.
One of the attractive properties of gallium is its low melting point and high boiling point. It has one of the widest liquid ranges of any element. Its melting point is solid at room temperature, but will begin to melt when held in your hand. When gallium freezes, it expands (like water when it freezes into ice). This means that you must be careful when storing liquid gallium to allow it to expand as the temperature drops.
Gallium is a fairly reactive element that readily reacts with acids and alkalis. It is usually found in the +3 oxidation state.
Highlights of Gallium:
| Symbol | Ga |
| Atomic Number | 31 |
| Atomic Weight | 69.723 |
| Classification | Post-transition or “other” metal |
| Phase at Room Temperature | Solid |
| Density | 5.91 grams per cm cubed |
| Melting Point | 29.76°C, 85.57°F |
| Boiling Point | 2204°C, 3999°F |
| Discovered by | Paul Emile Lecoq de Boisbaudran in 1875 |
Where is Gallium found on Earth?
Gallium is not found in elemental form on Earth, but it is found in minerals and ores in the earth’s crust. Most gallium is produced as a by-product of the mining of other metals, including aluminum (bauxite) and zinc (sphalerite).
How is Gallium used Today?
The main use of gallium is in high-speed semiconductors used to make cell phones, optoelectronics, solar panels and LEDs. Gallium is used to make the compounds gallium arsenide (GaAs) and gallium nitrite (GaN) that are used to make these devices.
Other uses of gallium include low-melting metal alloys, mirrors, and medical thermometers.
How was it discovered?
Gallium was first predicted by Russian chemist Dmitry Mendeleev. However, it was the French chemist Paul Emile Lecoq de Boisbaudran who first isolated the element in 1875 and is credited with discovering it.
Where did Gallium get its name?
Gallium takes its name from the Latin “Gallia” meaning “France” in honor of its discoverer’s country of origin.
Isotopes
Gallium has two stable isotopes found in nature: gallium-69 and gallium-71.
Interesting Facts about Gallium
A large amount of gallium is used at the Neutrino Observatory in Italy, where it is used to study solar neutrinos generated inside the Sun.
It is considered non-toxic and must not be used by plants or animals.
Gallium arsenide is used to make laser diodes that generate light from electricity. This is used over optical fibers to carry information over long distances.
Gallium is used to create a bright blue LED.
Gallium-based solar panels are used to power space applications such as satellites and Mars exploration missions.