Gallium is a chemical element with symbol Ga and atomic number 31. A soft silvery metallic poor metal, elemental gallium is a brittle solid at low temperatures. Held long enough, gallium will melt in the hand as it liquefies at temperature of 29.76 °C (85.57 °) (slightly above room temperature). Continue reading for more.
5. Beating Heart
Today, almost all gallium is used for microelectronics. Gallium arsenide, the primary use of gallium, is used in microwave circuitry and infrared applications. Gallium nitride and indium gallium nitride, minority semiconductor uses, produce blue and violet light-emitting diodes (LEDs) and diode lasers.
Gallium has no known role in biology. Because gallium(III) and ferric salts behave similarly in biological systems, gallium ions often mimic iron ions in medical applications. Gallium-containing pharmaceuticals and radiopharmaceuticals have been developed.
3. Heat Sink
The alloy Galinstan (68.5% Ga, 21.5% In, 10% Sn) has an even lower melting point of −19 °C (−2 °F), well below the freezing point of water. From its discovery in 1875 until the semiconductor era, gallium was used primarily as an agent to make low-melting alloys.
The unique melting point of gallium allows it to melt in one's hand, and then refreeze if removed. This metal has a strong tendency to supercool below its melting point/freezing point. Seeding with a crystal helps to initiate freezing.
1. Coke Can
Gallium's boiling point, 2477 K, is more than eight times higher than its melting point on the absolute scale, making it the greatest ratio between melting point and boiling point of any element.