Light blue metal, turning into silvery white liquid at 29.76℃. Liquid gallium is easily supercooled, that is, it will not solidify when cooled to 0℃. Slightly soluble in mercury, forming gallium amalgam. Gallium can penetrate glass, so it is not suitable for storage in glass containers.
When heated to the melting point, it becomes liquid, and then cooled to 0℃ without solidification. When it changed from liquid to solid, its volume increased by about 3.2%. The hardness is 1.5 ~ 2.5. Gallium is stable in dry air at room temperature.
It is easily hydrolyzed, especially at physiological pH value. Pure gallium is silvery white, can penetrate glass, has high boiling point and extremely low vapor pressure, about 1500℃.
Extended data:
Industrial use
Making semiconductor doping elements of gallium nitride, gallium arsenide, gallium phosphide and germanium; Pure gallium and low melting point alloys can be used as heat exchange media for nuclear reaction; Filling material of high temperature thermometer; Catalysts for diesters in organic reactions.
The industrial application of gallium is still primitive, although its unique properties may be applied in many aspects. Liquid gallium can be used in high-temperature thermometers and high-temperature manometers because of its wide temperature range and low vapor pressure. Gallium compounds, especially gallium arsenide, have attracted more and more attention in the electronic industry. There is no accurate world gallium production data, but the output in neighboring areas is only 20 tons/year. ?
Gallium -68 can emit positrons and can be used for positron tomography. ?
Gallium indium alloy can be used as a substitute for mercury.
References:
Baidu encyclopedia-gallium