Gallium is a chemical element represented by the symbol Ga. It is a weak silver-colored metal. It is a solid below 24.85 C, but it melts at only 29.77 C. It is in group 13 of the periodic table
Dmitri Mendeleev predicted the existence of gallium in 1871 and suggested that its properties would be similar to aluminium. However, it wasn’t until 1875 that gallium was discovered by Paul-Emile Lecoq de Boisbaudran who used electrolysis to separate it out from a solution.
Elemental gallium does not freely occur in nature, but instead occurs as gallium salts in trace amounts of bauxite and zinc ores. Gallium is often produced as a byproduct during the extraction of aluminum from bauxite. Purification of bauxite by the Bayer process results in a high concentration of gallium. Using electrolysis with a mercury electrode further concentrates the gallium output, and using a stainless steel cathode for electrolysis results in liquid gallium. Pure gallium should not be stored in metal or glass containers because the containers will break as the gallium begins to cool and expand. Although gallium is a solid at near-room temperature, it undergoes phase transition to a liquid at slightly less than 30 C. It has one of the longest liquid ranges of any metal; it boils at 2,205 C.