Is gallium metal radioactive?

Gallium is a kind of soft metal with white luster. The melting point was surprisingly low, with only 29.78. Take a particle of gallium in the palm of your hand, soon melts into small droplets to roll, like mercury beads like.

People have known this element for more than one hundred years. It is in 1875 by the French chemist Pu Bois found delang. Like the amount of about 0.0004% in the earth's crust, with tin almost, not too little. However, the tin concentration of gallium is very decentralized distribution in nature, almost no separate existence of gallium ore. So gallium is also known as "loose metal" ". Gallium is sometimes mixed with aluminum, which is found in bauxite. This is because gallium and aluminum in the elements of the periodic table are third main family, and gallium ions and aluminum ion size is similar, so they are easy to coexist in an ore. And because the size of gallium atoms and zinc atoms are close to, so gallium and zinc are also easy to be in the zinc ore. Gallium is also easy to coexist with germanium in coal. So the rest of the flue dust after the burning of coal contains trace amounts of gallium and germanium.

Many of the valuable properties of gallium are related to its purity. Refining with ordinary chemical methods, can only get a maximum of 99.99% purity, which is usually said of the nine four. For nearly half a century, people have made great progress in the purification of gallium, so as to promote the application of gallium.

The chemical properties of gallium and aluminum are very similar, and the same family of indium, thallium is very similar. At ordinary temperatures, gallium does not change in dry air. Only when red hot, can be air oxidation. Gallium is also very stable to water. At room temperature, metal images can be strongly strongly with chlorine or bromine. Sulfuric acid, in particular, is easily dissolved in hydrochloric acid. Strong acid or ammonium hydroxide solution is easily dissolved gallium. Gallium hydroxide can be dissolved in alkali solution, generating gallate. Gallium hydroxide acidic aluminum hydroxide is stronger than some. In chemistry, it is called "sexual". That is, the substance is not only alkaline, but also acidic.

The melting point of gallium is very low. It is not easy to solidify after melting. When gallium is in a liquid state, the volume of the heated volume is evenly expanded. The boiling point of gallium is as high as 2070. From the melting point of 30 to the boiling point of 2070 degrees Celsius temperature range is wide, so that gallium can do high temperature thermometer material. An ordinary mercury thermometer can do nothing to measure the high temperature of the furnace and the atomic energy reactor.

People also use the characteristics of low melting point of the crops, the gallium and zinc, tin, steel these metals are blended together, made of low melting point alloy, it uses automatic fire leading switch. Once the fire happens, the melting temperature, switch fuse fusible alloy do, water from the tap automatic fire extinguishing spray.

Liquid gallium is also used to replace mercury, used in a variety of high vacuum pumps, or ultraviolet light bulbs. In an atomic reactor, gallium is used as a heat conducting medium to heat the heat from the reactor. Gallium can be glued to the glass, so that it can be made into a mirror, which is used on some special optical instruments.

GA has some wonderful features. Most of the metal is thermal expansion and contraction. However, it is cold expansion and thermal shrinkage of gallium. When gallium is condensed from liquid to solid, the volume is expanded by 3%. So, as opposed to most metals, the specific gravity of the liquid is larger than that of the solid. Therefore, the metal grain should be stored in containers of plastic or rubber. If installed in a glass bottle, once the liquid gallium solidified, the volume expansion, will break the bottle.

Corn belongs to the periodic table of the elements of group third. It and the fifth elements: arsenic, antimony, phosphorus and nitrogen compounds, the formation of a series of compounds with semiconducting properties. As GaAs, GaSb, phosphide and has good performance of semiconductor, is currently more practical application of semiconductor materials.

Originally the vacuum tube as the core of the electronic devices are mostly bulky. Since the emergence of semiconductor materials such as gallium, the volume of electronic devices has been greatly reduced, thus realizing the miniaturization, miniaturization, and even making integrated circuits. Cause a profound revolution in the field of electronics industry. The compound of arsenic and gallium, a new type of semiconductor material with excellent performance, has been developed in recent years. GaAs lasers can be made from GaAs. This is a new type of laser with high efficiency and small size. Gallium and phosphorus compounds -- gap is a kind of semiconductor light emitting materials. It can emit red or green light. People make it into a variety of Arabia digital shapes. In some of the electronic computers, use it to display the results.

There is also a strange characteristic of metal gallium, that is, when it is at low temperature, there is a good "superconductivity" ". At near absolute zero, the resistance becomes extremely low, almost equal to zero, -273. At this time, it's conductive performance is very good. If the electricity is energized at such a low temperature, the loss of the current is negligible. This property is called superconductivity ". As early as 1911, the phenomenon of superconductivity has been discovered. Using superconducting materials to manufacture motor, not only can save energy consumption, but also greatly save raw materials. A conventional eight thousand horsepower motor weighs 379 tons, the superconducting material after weighing only 40 tons. Total cost fell by half. To build more than 5 million kilowatts of large electrical machines, almost non superconducting technology can not be used. Using superconducting materials for long distance transmission lines is very economical, transmission efficiency can reach more than 99.5%, and the loss is very little.