Properties | More Info | Isotopes | Spectra
Compounds | Reactions | Production
Atomic: M.A.C. | Reference
Images | Video
Gallium [Ga]
CAS-ID: 7440-55-3
An: 31 N: 39
Am: 69.723 g/mol
Group No: 13
Group Name: Metals
Block: p-block  Period: 4
State: solid at 298 K (but melts only slightly above this temperature)
Colour: silvery white Classification: Metallic
Boiling Point: 2477K (2204°C)
Melting Point: 302.91K (29.76°C)
Superconducting temperature: 1.083K (-272.067°C)
Density: 5.91g/cm3
Discovery Information
Who: Paul emile Lecoq de Boisbaudran
When: 1875
Where: France
Name Origin
Paul named the element after his native land of France and, in a multilingual pun, after himself, as 'Lecoq' = the rooster, and Latin for rooster is "gallus".
 "Gallium" in different languages.
Found throughout the crust in minerals like bauxite, germanite (Cu13Fe2Ge2S16) (as an impurity) and coal, but does not exist in pure form in nature. Around 30 tons are produced each year.
 Universe: 0.01 ppm (by weight)
 Sun: 0.04 ppm (by weight)
 Carbonaceous meteorite: 7.8 ppm
 Earth's Crust: 18 ppm
 Seawater: 3 x 10-5 ppm
Used in semiconductor production, quartz thermometers, laser diodes, used to locate tumors and for creating mirrors. Gallium Gadolinium Garnet (Gd3Ga5O12) is a material with good optical properties, and is used in fabrication of various optical components and as substrate material for magneto-optical films.
Gallium is the rarest component of new photovoltaic compounds (such as copper indium gallium selenium sulphide or Cu(In,Ga)(Se,S)2, recently announced by South African researchers) for use in solar panels as an alternative to crystalline silicon, which is currently in short supply.
It has been suggested that a liquid gallium-tin alloy could be used to cool computer chips in place of water. As it conducts heat approximately 65 times better than water it makes a considerably better coolant.
Gallium was discovered spectroscopically by Lecoq de Boisbaudran in 1875 by its characteristic spectrum (two violet lines) in an examination of a zinc blende from the Pyrenees. Before its discovery, most of its properties had been predicted and described by Dmitri Mendeleev (who called the hypothetical element eka-aluminium) on the basis of its position in his periodic table. Later, in 1875, Boisbaudran obtained the free metal through the electrolysis of its hydroxide in KOH solution. He named the element "gallia" after his native land of France. It was later claimed that, in one of those multilingual puns so beloved of men of science of the early 19th century, he also named it after himself, as 'Lecoq' = the rooster, and Latin for rooster is "gallus"; however, he denied this in an 1877 article.
Gallium, along with caesium and mercury, is one of the few metals that are liquid at (or near) room temperature. It will melt if held in your hand.
Gallium also corrodes most other metals by diffusing into their metal lattice. It is very important to keep gallium away from any type of metal containers such as steel or aluminium.
Harmful if swallowed, inhaled or of it comes in to contact with skin. Corrosive, causes burns.
Some sources suggest that it may cause dermatitis from prolonged exposure; other tests have not caused a positive reaction. It will however stain your skin if you hold it in your bare hands.