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Where is gallium mined? Gallium




Gallium is an element of the main subgroup of the third group of the fourth period of the periodic system of chemical elements of D. I. Mendeleev, with atomic number 31. It is designated by the symbol Ga (lat. Gallium). Belongs to the group of light metals. The simple substance gallium is a soft, ductile silver-white metal with a bluish tint.

Atomic number - 31

Atomic mass - 69.723

Density, kg/m³ - 5910

Melting point, ° С - 29.8

Heat capacity, kJ / (kg ° С) - 0.331

Electronegativity - 1.8

Covalent radius, Å - 1.26

1st ionization potential, ev - 6.00

The history of the discovery of gallium

The French chemist Paul Emile Lecoq de Boisbaudran went down in history as the discoverer of three new elements: gallium (1875), samarium (1879) and dysprosium (1886). The first of these discoveries brought him fame.

At that time, outside of France, he was little known. He was 38 years old, he was mainly engaged in spectroscopic research. Lecoq de Boisbaudran was a good spectroscopist, and this ultimately led to success: he discovered all three of his elements by spectral analysis.

In 1875, Lecoq de Boisbaudran investigated the spectrum of zinc blende brought from Pierrefitte (Pyrenees). It was in this spectrum that a new violet line was discovered. The new line indicated the presence of an unknown element in the mineral, and, quite naturally, Lecoq de Boisbaudran made every effort to isolate this element. This was not easy to do: the content of the new element in the ore was less than 0.1%, and in many ways it was similar to zinc*. After lengthy experiments, the scientist managed to get a new element, but in a very small amount. So small (less than 0.1 g) that Lecoq de Boisbaudran could not fully study its physical and chemical properties.

The announcement of the discovery of gallium - so in honor of France (Gallia - its Latin name) a new element was named - appeared in the reports of the Paris Academy of Sciences.

This message was read by D.I. Mendeleev recognized ekaaluminum, which he had predicted five years earlier, in gallium. Mendeleev immediately wrote to Paris. “The method of discovery and isolation, as well as the few properties described, suggest that the new metal is nothing more than ekaaluminum,” his letter said. It then repeated the predicted properties for that element. Moreover, never holding a grain of gallium in his hands, without seeing it in his eyes, the Russian chemist claimed that the discoverer of the element was mistaken, that the density of the new metal cannot be equal to 4.7, as Lecoq de Boisbaudran wrote, - it must be more about 5.9...6.0 g/cm3! But experience has shown the opposite: the discoverer was mistaken. The discovery of the first of the elements predicted by Mendeleev significantly strengthened the position of the periodic law.

Finding Gaulin nature

The average content of gallium in the earth's crust is 19 g/t. Gallium is a typical trace element with a dual geochemical nature. The only Gallium mineral, CuGaS 2 gallite, is very rare. The geochemistry of Gallium is closely related to the geochemistry of aluminum, which is due to the similarity of their physicochemical properties. The main part of Gallium in the lithosphere is enclosed in aluminum minerals. Due to the closeness of its crystal chemical properties with the main rock-forming elements (Al, Fe, etc.) and the wide possibility of isomorphism with them, gallium does not form large accumulations, despite the significant clarke value. The following minerals with a high content of gallium are distinguished: sphalerite (0 - 0.1%), magnetite (0 - 0.003%), cassiterite (0 - 0.005%), garnet (0 - 0.003%), beryl (0 - 0.003%), tourmaline (0 - 0.01%), spodumene (0.001 - 0.07%), phlogopite (0.001 - 0.005%), biotite (0 - 0.1%), muscovite (0 - 0.01%), sericite ( 0 - 0.005%), lepidolite (0.001 - 0.03%), chlorite (0 - 0.001%), feldspars (0 - 0.01%), nepheline (0 - 0.1%), hecmanite (0.01 - 0.07%), natrolite (0 - 0.1%).

Physical properties Gaul

Perhaps the most famous property of gallium is its melting point, which is 29.76 °C. It is the second most fusible metal in the periodic table (after mercury). This allows you to melt metal while holding it in your hand. Gallium is one of the few metals that expand when the melt solidifies (others are Bi, Ge).

Crystalline gallium has several polymorphic modifications, however, only one (I) is thermodynamically stable, having an orthorhombic (pseudotetragonal) lattice with parameters a = 4.5186 Å, b = 7.6570 Å, c = 4.5256 Å. Other modifications of gallium (β, γ, δ, ε) crystallize from supercooled dispersed metal and are unstable. At elevated pressure, two more polymorphic structures of gallium II and III were observed, having, respectively, cubic and tetragonal lattices.

The density of gallium in the solid state at T=20°C is 5.904 g/cm³.

One of the features of gallium is a wide temperature range for the existence of a liquid state (from 30 to 2230 °C), while it has a low vapor pressure at temperatures up to 1100÷1200 °C. The specific heat capacity of solid gallium in the temperature range T=0÷24 °C is 376.7 J/kg K (0.09 cal/g deg.), in the liquid state at T=29÷100 °C - 410 J/ kg K (0.098 cal/g deg).

The electrical resistivity in the solid and liquid states are, respectively, 53.4 10 −6 ohm cm (at T=0 °C) and 27.2 10 −6 ohm cm (at T=30 °C). The viscosity of liquid gallium at different temperatures is 1.612 poise at T=98°C and 0.578 poise at T=1100°C. The surface tension measured at 30 °C in a hydrogen atmosphere is 0.735 N/m. The reflection coefficients for the wavelengths of 4360 Å and 5890 Å are 75.6% and 71.3%, respectively.

Natural gallium consists of two isotopes 69 Ga (61.2%) and 71 Ga (38.8%). The thermal neutron capture cross section is 2.1·10 −28 m² and 5.1·10 −28 m², respectively.

Gallium is a low toxic element. Due to the low melting point, gallium ingots are recommended to be transported in polyethylene bags, which are poorly wetted by the gallium melt. At one time, the metal was even used to make fillings (instead of amalgam fillings). This application is based on the fact that when copper powder is mixed with molten gallium, a paste is obtained, which hardens after a few hours (due to the formation of an intermetallic compound) and then can withstand heating up to 600 degrees without melting.

At high temperatures, gallium is a very aggressive substance. At temperatures above 500 °C, it corrodes almost all metals except tungsten, as well as many other materials. Quartz is resistant to molten gallium up to 1100°C, but a problem can arise because quartz (as well as most other glasses) is highly wettable by this metal. That is, gallium will simply stick to the walls of quartz.

Chemical properties Gaul

The chemical properties of gallium are close to those of aluminum. The oxide film formed on the metal surface in air protects gallium from further oxidation. When heated under pressure, gallium reacts with water, forming the compound GaOOH by the reaction:

2Ga + 4H 2 O = 2GaOOH + 3H 2 .

Gallium interacts with mineral acids with the release of hydrogen and the formation of salts, and the reaction proceeds even below room temperature:

2Ga + 6HCl = 2GaCl 3 + 3H 2

The reaction products with alkalis and potassium and sodium carbonates are hydroxogallates containing Ga (OH) 4 - and, possibly, Ga (OH) 6 3 - and Ga (OH) 2 - ions:

2Ga + 6H 2 O + 2NaOH = 2Na + 3H 2

Gallium reacts with halogens: the reaction with chlorine and fluorine occurs at room temperature, with bromine - already at -35 ° C (about 20 ° C - with ignition), interaction with iodine begins when heated.

Gallium does not interact with hydrogen, carbon, nitrogen, silicon and boron.

At high temperatures, gallium is capable of destroying various materials and its action is stronger than the melt of any other metal. So, graphite and tungsten are resistant to the action of a gallium melt up to 800 ° C, alundum and beryllium oxide BeO - up to 1000 ° C, tantalum, molybdenum and niobium are resistant up to 400 ÷ 450 ° C.

With most metals, gallium forms gallides, with the exception of bismuth, as well as metals of the zinc, scandium, and titanium subgroups. One of the gallides V 3 Ga has a rather high superconducting transition temperature of 16.8 K.

Gallium forms polymeric hydrides:

4LiH + GaCl 3 = Li + 3LiCl.

The ion stability decreases in the series BH 4 - → AlH 4 - → GaH 4 - . Ion BH 4 - stable in aqueous solution, AlH 4 - and GaH 4 - quickly hydrolyze:

GaH 4 - + 4H 2 O \u003d Ga (OH) 3 + OH - + 4H 2 -

When Ga (OH) 3 and Ga 2 O 3 are dissolved in acids, aqua complexes 3+ are formed, therefore, gallium salts are isolated from aqueous solutions in the form of crystalline hydrates, for example, gallium chloride GaCl 3 * 6H 2 O, potassium gallium alum KGa (SO 4) 2 * 12H2O.

The interaction of gallium with sulfuric acid is interesting. It is accompanied by the release of elemental sulfur. In this case, sulfur envelops the surface of the metal and prevents its further dissolution. If, however, the metal is washed with hot water, the reaction will resume, and will continue until a new “skin” of sulfur grows on the gallium.

Basic connections Gaul
  • Ga2H6- volatile liquid, t pl −21.4 °C, bp t 139 °C. In ethereal suspension with lithium or thallium hydrate, it forms LiGaH 4 and TlGaH 4 compounds. It is formed as a result of the treatment of tetramethyldigallane with triethylamine. There are banana bonds, as in diborane
  • Ga2O3- white or yellow powder, t pl 1795 °C. It exists in the form of two modifications. α- Ga 2 O 3 - colorless trigonal crystals with a density of 6.48 g / cm³, slightly soluble in water, soluble in acids. β- Ga 2 O 3 - colorless monoclinic crystals with a density of 5.88 g / cm³, slightly soluble in water, acids and alkalis. Obtained by heating metallic gallium in air at 260 °C or in an oxygen atmosphere, or by calcining gallium nitrate or sulfate. ΔH° 298(arr) −1089.10 kJ/mol; ΔG° 298(arr) −998.24 kJ/mol; S° 298 84.98 J/mol*K. They show amphoteric properties, although the main properties, in comparison with aluminum, are enhanced:

Ga 2 O 3 + 6HCl \u003d 2GaCl 2 Ga 2 O 3 + 2NaOH + 3H 2 O \u003d 2Na Ga 2 O 3 + Na 2 CO 3 \u003d 2NaGaO 2 + CO 2

  • Ga(OH)3- precipitates in the form of a jelly-like precipitate during the treatment of solutions of salts of trivalent gallium with hydroxides and carbonates of alkali metals (pH 9.7). It dissolves in concentrated ammonia and concentrated ammonium carbonate solution, precipitates when boiled. By heating, gallium hydroxide can be converted to GaOOH, then to Ga 2 O 3 *H 2 O, and finally to Ga 2 O 3. Can be obtained by hydrolysis of salts of trivalent gallium.
  • GaF3- White powder. t pl > 1000 ° C, t kip 950 ° C, density - 4.47 g / cm³. Slightly soluble in water. Known crystalline GaF 3 ·3H 2 O. Obtained by heating gallium oxide in a fluorine atmosphere.
  • GaCl3- colorless hygroscopic crystals. t pl 78 ° C, t kip 215 ° C, density - 2.47 g / cm³. Let's well dissolve in water. Hydrolyzes in aqueous solutions. Obtained directly from the elements. It is used as a catalyst in organic syntheses.
  • GaBr3- colorless hygroscopic crystals. t pl 122 ° C, t kip 279 ° C density - 3.69 g / cm³. Dissolves in water. Hydrolyzes in aqueous solutions. Slightly soluble in ammonia. Obtained directly from the elements.
  • GaI 3- hygroscopic light yellow needles. t pl 212 ° C, t kip 346 ° C, density - 4.15 g / cm³. Hydrolyzes with warm water. Obtained directly from the elements.
  • GaS 3- yellow crystals or white amorphous powder with t pl 1250 °C and density 3.65 g/cm³. It interacts with water, while completely hydrolyzing. Obtained by the interaction of gallium with sulfur or hydrogen sulfide.
  • Ga 2 (SO 4) 3 18H 2 O- a colorless, highly soluble substance in water. It is obtained by the interaction of gallium, its oxide and hydroxide with sulfuric acid. With sulfates of alkali metals and ammonium, it easily forms alums, for example, KGa (SO 4) 2 12H 2 O.
  • Ga(NO 3) 3 8H 2 O- colorless crystals, soluble in water and ethanol. When heated, it decomposes to form gallium (III) oxide. Obtained by the action of nitric acid on gallium hydroxide.
Obtaining gallium

The main source of Gallium is aluminum production. Gallium during the processing of bauxite by the Bayer method is concentrated in the circulating mother liquors after the allocation of Al(OH) 3 . Gallium is isolated from such solutions by electrolysis on a mercury cathode. From the alkaline solution obtained after treatment of the amalgam with water, Ga(OH) 3 is precipitated, which is dissolved in alkali and Gallium is isolated by electrolysis.

With the soda-lime method of processing bauxite or nepheline ore, Gallium is concentrated in the last fractions of sediments released during carbonization. For additional enrichment, the precipitate of hydroxides is treated with milk of lime. In this case, most of the Al remains in the precipitate, and Gallium passes into solution, from which gallium concentrate (6-8% Ga 2 O 3) is isolated by passing CO 2; the latter is dissolved in alkali and gallium is isolated electrolytically.

The residual anodic alloy of the Al refining process by the three-layer electrolysis method can also serve as a source of Gallium. In the production of zinc, the sources of Gallium are sublimates (Weltz oxides) formed during the processing of leaching tailings of zinc cinders.

Liquid Gallium obtained by electrolysis of an alkaline solution, washed with water and acids (HCl, HNO 3), contains 99.9-99.95% Ga. A purer metal is obtained by vacuum melting, zone melting, or by drawing a single crystal from the melt.

The use of gallium

Gallium arsenide GaAs is a promising material for semiconductor electronics.

Gallium nitride is used in the creation of semiconductor lasers and LEDs in the blue and ultraviolet range. Gallium nitride has excellent chemical and mechanical properties typical of all nitride compounds.

As an element of group III, which contributes to the enhancement of "hole" conductivity in a semiconductor, gallium (with a purity of at least 99.999%) is used as an additive to germanium and silicon. Intermetallic compounds of gallium with elements of the V group - antimony and arsenic - themselves have semiconductor properties.

The gallium-71 isotope is the most important material for detecting neutrinos, and in this regard, technology faces a very urgent task of isotope separation from a natural mixture in order to increase the sensitivity of neutrino detectors. Since the content of 71 Ga in the natural mixture of isotopes is about 39.9%, the isolation of a pure isotope and its use as a neutrino detector can increase the detection sensitivity by 2.5 times.

The addition of gallium to the glass mass makes it possible to obtain glasses with a high refractive index of light rays, and glasses based on Ga 2 O 3 transmit infrared rays well.

Gallium is expensive, in 2005 a ton of gallium cost 1.2 million US dollars on the world market, and due to the high price and at the same time the great demand for this metal, it is very important to establish its complete extraction in aluminum production and coal processing at liquid fuel.

Liquid gallium reflects 88% of the light falling on it, solid - a little less. Therefore, gallium mirrors are very easy to manufacture - a gallium coating can even be applied with a brush.

Gallium has a number of alloys that are liquid at room temperature, and one of its alloys has a melting point of 3 °C, but on the other hand, gallium (alloys to a lesser extent) is very aggressive to most structural materials (cracking and erosion of alloys at high temperature), and as a coolant, it is ineffective, and often simply unacceptable.

Attempts have been made to use gallium in nuclear reactors, but the results of these attempts can hardly be considered successful. Not only does gallium quite actively capture neutrons (capture cross section of 2.71 barns), it also reacts at elevated temperatures with most metals.

Gallium did not become an atomic material. True, its artificial radioactive isotope 72 Ga (with a half-life of 14.2 hours) is used to diagnose bone cancer. Gallium-72 chloride and nitrate are adsorbed by the tumor, and by fixing the radiation characteristic of this isotope, doctors almost accurately determine the size of foreign formations.

Gallium is an excellent lubricant. On the basis of gallium and nickel, gallium and scandium, practically very important metal adhesives have been created.

Gallium metal is also filled into quartz thermometers (instead of mercury) to measure high temperatures. This is because gallium has a much higher boiling point than mercury.

Gallium oxide is a component of a number of strategically important laser materials.

Gallium production in the world

Its world production does not exceed two hundred tons per year. With the exception of two recently discovered deposits - in 2001 in Gold Canion, Nevada, USA and in 2005 in Inner Mongolia, China - gallium is not found anywhere in the world in industrial concentrations. (In the latter deposit, the presence of 958 thousand tons of gallium in coal was established - this is a doubling of the world's gallium resources).

World resources of gallium in bauxite alone are estimated to exceed 1 million tons, and in the mentioned deposit in China 958 thousand tons of gallium in coal - doubling the world resources of gallium).

There are not many gallium producers. GEO Gallium is one of the leaders in the gallium market. Its main facilities until 2006 consisted of a plant in Stade (Germany), which produces about 33 tons per year, a plant in Salindres, processing 20 tons / year (France) and in Pinjarra (Western Australia) - potential (but not commissioned in system) capacity up to 50 tons/year.

In 2006, the position of the No. 1 producer weakened - the Stade enterprise was bought by the British MCP and the American Recapture Metals.

The Japanese company Dowa Mining is the world's only producer of primary gallium from zinc concentrates as a by-product of zinc production. Dowa Mining's total raw material capacity is estimated at up to 20 tons/year. In Kazakhstan, the Aluminum of Kazakhstan plant in Pavlodar has a total capacity of up to 20 tons/year.

China has become a very serious supplier of gallium. In China, there are 3 major producers of primary gallium - Geatwall Aluminum Co. (up to 15 tons/year), Shandong Aluminum Plant (about 6 tons/year) and Guizhou Aluminum Plant (up to 6 tons/year). There are also a number of co-productions. Sumitomo Chemical has set up a joint venture in China with a capacity of up to 40 tons/year. The American firm AXT has established a joint venture with the largest Chinese aluminum enterprise Shanxi Aluminum Factory Beijing JiYa semiconductor Material Co. with a capacity of up to 20 tons / year.

Gallium production in Russia

In Russia, the structure of gallium production is determined by the formation of the aluminum industry. The two leading groups that announced the merger - Russian Aluminum and SUAL - are the owners of gallium sites created at alumina refineries.

Russian Aluminum: Nikolaev Alumina Refinery in Ukraine (classical Bayer hydrochemical method for tropical bauxite processing, site capacity - up to 12 tons of gallium / year) and Achinsk Alumina Refinery in Russia (processing by sintering of nepheline raw materials - urtites from the Kiya-Shaltyrsky deposit of the Krasnoyarsk Territory, section capacity is 1.5 tons of gallium/year).

SUAL: Capacities in Kamensk-Uralsky (Bayer-sintering technology of bauxites of the North Ural bauxite ore region, site capacity - up to 2 tons of gallium / year), at the Boksitogorsk alumina plant (processes bauxites of the Leningrad region by sintering, capacity - 5 tons of gallium / year, currently mothballed) and Pikalevsky alumina (processes nepheline concentrates from apatite-nepheline ores of the Murmansk region by sintering, the capacity of the site is 9 tons of gallium / year). In total, all enterprises of Rusal and SUAL can produce over 20 tons/year.

The actual production is lower - for example, in 2005, 8.3 tons of gallium were exported from Russia and 13.9 tons of gallium from the Nikolaev Alumina Refinery from Ukraine.

In preparing the material, information from the Kvar company was used.


And here is another use of gallium. True, in this form it was quite unexpected for me.
Gallium is in a liquid state in a very wide temperature range, and, in theory, gallium thermometers could measure temperatures up to 2000 degrees. For the first time, the use of gallium as a thermometric liquid was proposed quite a long time ago. For example, I read about it in a reference book from the sixties, and also saw it many times in popular science books on chemistry (in particular, in the Popular Library of Chemical Elements). It was said that gallium thermometers already measure temperatures up to 1200 degrees, but it is not often possible for an ordinary person to see these thermometers live in the laboratory.
I think that such thermometers are not widely used for several reasons. First, at high temperatures, gallium is a very aggressive substance. At temperatures above 500 °C, it corrodes almost all metals except tungsten, as well as many other materials. Quartz is resistant to molten gallium up to 1100°C, but a problem can arise because quartz (as well as most other glasses) is highly wettable by this metal. That is, gallium will simply stick to the walls of the thermometer from the inside, and it will be impossible to know the temperature. Another problem can arise when the thermometer is cooled below 28 degrees. When solidifying, gallium behaves like water - it expands and can simply break the thermometer from the inside. Well, the last reason why a high-temperature gallium thermometer is now very rare is the development of technology and electronics. It is no secret that a digital thermometer is much more convenient to use than a liquid one. Modern temperature controllers, complete with, for example, platinum-platinum-rhodium thermocouples, make it possible to measure temperatures in the range from -200 to +1600°C with an accuracy unattainable for liquid thermometers. In addition, the thermocouple may be located at a considerable distance from the controller.
I found the thermometer in the photo on a German ebay auction after about a year and a half of searching.

What is 29.76 o C. If you place it in a warm palm, it gradually begins to move from a solid state to a liquid form.

A brief excursion into history

What is the name of the metal that melts in the hand? As noted above, such a material is known under the definition of gallium. Its theoretical existence was predicted back in 1870 by a Russian scientist, the author of a table of chemical elements - Dmitry Mendeleev. The basis for the emergence of such an assumption was his study of the properties of numerous metals. At that time, not a single theorist could have imagined that the metal that melts in the hands exists in reality.

The possibility of synthesizing an extremely fusible material, the appearance of which Mendeleev predicted, was proved by the French scientist Emile Lecoq de Boisbaudran. In 1875, he managed to isolate gallium from zinc ore. During experiments with the material, the scientist received a metal that melts in his hands.

It is known that Émile Boisbaudran experienced significant difficulties in isolating a new element from zinc ore. During the first experiments, he managed to extract only 0.1 grams of gallium. However, even this was enough to confirm the amazing property of the material.

Where is gallium found in nature?

Gallium is one of the elements that do not occur as ore deposits. The material is very dispersed in the earth's crust. In nature, it is found in extremely rare minerals such as gallite and zengeite. In the course of laboratory experiments, a small amount of gallium can be isolated from the ores of zinc, aluminum, germanium, and iron. Sometimes it is found in bauxite, coal deposits, and other mineral deposits.

How is gallium obtained

Currently, scientists most often synthesize a metal that melts in their hands from aluminum solutions that are mined during the processing of alumina. As a result of removing the main mass of aluminum and carrying out the procedure of repeated concentration of metals, an alkaline solution is obtained, in which there is an insignificant fraction of gallium. Allocate such material from solution by electrolysis.

Applications

Gallium has not found industrial use to this day. This is due to the widespread use of aluminum, which has similar properties in solid form. Despite this, gallium looks like a promising material, since it has excellent semiconductor properties. Such a metal can potentially be used for the production of transistor elements, high-temperature rectifiers, and solar batteries. Gallium looks like an excellent solution for making optical mirror coatings that will have the highest reflectivity.

The main obstacle to the use of gallium on an industrial scale remains the high cost of its synthesis from ores and minerals. The price per ton of such metal in the world market is more than 1.2 million dollars.

To date, gallium has found effective use only in the field of medicine. The metal in liquid form is used to slow down bone loss in people suffering from cancer. It is used to quickly stop bleeding in the presence of extremely deep wounds on the body of the victims. In the latter case, blockage of vessels with gallium does not lead to the formation of blood clots.

As noted above, gallium is a metal that melts in the hands. Since the temperature required for the transition of the material to a liquid state is slightly more than 29 ° C, it is enough to hold it in the palms of your hands. After a while, the initially solid material will begin to melt right before our eyes.

A rather fascinating experiment can be carried out with the solidification of gallium. The presented metal tends to expand during solidification. To conduct an interesting experiment, it is enough to place liquid gallium in a glass vial. Next, you need to start cooling the container. After a while, you can notice how metal crystals begin to form in the bubble. They will have a bluish color, as opposed to the silvery hue that is characteristic of the material in its liquid state. If the cooling is not stopped, the crystallizing gallium will eventually burst the glass bubble.

Finally

So we found out which metal melts in the hand. Today, gallium can be found on sale for your own experiments. However, the material must be handled with extreme care. Solid gallium is non-toxic. However, prolonged contact with the material in liquid form can lead to the most unforeseen health consequences, up to respiratory arrest, paralysis of the limbs and the entry of a person into a coma.

Anyone whose knowledge in a chemistry lesson was graded as excellent, definitely knows about the existence of such a chemical element from the well-known table as gallium. In 1875, during research, a new chemical element was discovered in zinc samples.

gallium metal

Gallium is a steel-colored metal that is in a solid state at low temperatures. However, as soon as the temperature rises to 29 degrees, the metal begins to turn into a liquid substance. Given that the temperature of the human body is above 30 degrees, you can watch how solid gallium turns into liquid metal right in your palm.

But even here the properties of gallium are not exhausted. It can withstand temperatures up to 2230 degrees, which is why it is the most suitable material in the production of high temperature thermometers. Today, anyone who wants to see for himself the properties of this unusual element No31 from the periodic table can buy gallium.

Gallium is a soft and brittle metal that easily changes shape, and it is impossible to find it in nature in its pure form. Many are wondering where to get gallium, because this element is not easily mined, which means that its cost should be quite high. You can buy gallium in Moscow and other cities of Russia through an online store.

Gallium

The element is transported in special plastic vials, since the metal can change its shape several times until it reaches its destination. However, not everyone orders gallium in order to satisfy their interest. Anyone who knows where gallium is used has long been able to find its use in everyday life.

The available melting point of gallium allows the element to be deposited on any plane. It is gallium Gallium Ga that allows you to turn a simple into a mirror surface. Turn the mirror over and on the back you will see a silver coating, this is this element.

Knowing where to buy gallium, you can easily restore the surface of old mirrors, eliminate scratches and darkening. The coating is also used in the manufacture of stained-glass windows and crafts made of transparent material (plastic or glass). Well, by adding metal directly to the composition of the glass, you can get an excellent reflective accessory.

The use of gallium has found its place in dentistry. It is also an excellent material for fire alarms. That is why it starts to work even in the absence of open fire. A sharp increase in room temperature can serve as an alarm bell for such a device.

A non-toxic element, safe for health, is successfully used in the composition for filling teeth. However, the direct interaction of the metal with the human body will be detrimental. Therefore, when buying liquid gallium metal, take all precautions and do not use it as a toy for children.

It is worth buying gallium metal for conducting experiments in chemistry lessons. The teacher will be able to explain to the students and clearly prove that gallium is an element that can change its shape and state. The price of gallium allows you to purchase this element for use in chemistry lessons.

And of course, gallium is a great way to study poorly at school. Indeed, in a liquid state, the metal is very similar to mercury, but this element is not toxic and is completely safe for a short interaction with the skin. Surprise your friends by showing how solid alloy turns into a liquid mass in your palms.

You can buy gallium in St. Petersburg only in the online store, because the element cannot be found on the shelves. Not everyone knows how much gallium costs, and you can easily tell uninformed friends any funny fictional story about how you got it.

For adults, this will be an excellent opportunity to tell your children where gallium is used and explain how a mirror surface is made from plain glass. And although the use in everyday life is not great, but every student will remember this experience with liquid-solid metal for a lifetime.

The weight of the contents of the plastic vial is small. It contains only 20 grams of 99.9% gallium. But for a visual experiment, you don’t need more, and everyone can buy gallium at a low price.

Liquid metal Gallium. Peculiarities

  • Sold in sealed plastic packaging;
  • It will be a great exhibit for a chemistry lesson;
  • Helps to restore the mirror surface;
  • Easily changes from solid to liquid state and vice versa;
  • It will give you the opportunity to embody all creative fantasies in the manufacture of stained-glass windows.

By knowing where to buy gallium, you can witness the element's simple yet mysterious reaction. A drop of a liquid substance in the palm of your hand will look funny, because the metal does not melt to the state of water, and can easily change shape right in your hand. Remember to take precautions when using this magical substance. At a low price, gallium metal is worth buying for anyone who wants to hold a small piece of a magical element in their hands.

Characteristics

  • Material: gallium 99.99%;
  • Melting point: 29°C;
  • Weight: 20g

Equipment

  • 1 x Gallium in sealed plastic packaging.

Gallium

GALLIUM-I; m.[from lat. Gallia - France] Chemical element (Ga), soft fusible silver-white metal (used in the production of semiconductors).

Gallium

(lat. Gallium), a chemical element of group III of the periodic system. The name is from Gallia, the Latin name for France. Silvery white fusible ( t mp 29.77ºC) metal; density (g / cm 3) of solid metal 5.904, liquid 6.095; t kip 2205ºC. Chemically resistant to air. Dispersed in nature, found together with Al. They are mainly used (97%) in the production of semiconductor materials (GaAs, GaSb, GaP, GaN).

GALLIUM

GALLIUM (lat. Gallium, from Gallia - the Latin name for France), Ga (read "gallium"), a chemical element with atomic number 31, atomic mass 69.723.
Natural gallium consists of two isotopes 69 Ga (61.2% by weight) and 71 Ga (38.8%). Outer electron layer configuration 4 s 2 p one . The oxidation state is +3, +1 (valencies I, III).
Located in group IIIA of the periodic system of elements, in the 4th period.
The radius of the atom is 0.1245 nm, the radius of the Ga 3+ ion is 0.062 nm. Sequential ionization energies 5.998, 20.514, 30.71, 64.2 and 89.8 eV. Electronegativity according to Pauling (cm. PAULING Linus) 1,6.
Discovery history
For the first time, the existence of this element was predicted by D. I. Mendeleev (cm. MENDELEEV Dmitry Ivanovich) in 1871 on the basis of the periodic law discovered by him. He named it ekaaluminum. In 1875 P. E. Lecoq de Boisbaudran (cm. Lecoq de Boisbaudran Paul Emil) isolated gallium from zinc ores.
De Boisbaudran determined the density of gallium - 4.7 g / cm 3, which did not correspond to the value predicted by D. I. Mendeleev of 5.9 g / cm 3. The refined value of the density of gallium (5.904 g/cm3) coincided with Mendeleev's prediction.
Being in nature
The content in the earth's crust is 1.8 10 -3% by weight. Gallium is a trace element. It occurs in nature in the form of very rare minerals: zengeite Ga(OH) 3 , gallite CuGaS 2 and others. Is a companion of aluminum (cm. ALUMINUM), zinc (cm. ZINC (chemical element)), Germany (cm. GERMANIUM), gland (cm. IRON); found in sphalerite (cm. sphalerite), nepheline (cm. NEFELIN), trolite, bauxite, (cm. BOXITES) germanite, in coals and iron ores of some deposits.
Receipt
The main source of gallium is aluminate solutions obtained during the processing of alumina. After removal of most of the Al and repeated concentration, an alkaline solution containing Ga and Al is formed. Gallium is isolated by electrolysis of this solution.
Physical and chemical properties
Gallium is a low-melting light gray metal with a bluish tint. The Ga melt can be in a liquid state at a temperature below the melting point (29.75 °C). The boiling point is 2200 ° C, this is due to the fact that in liquid gallium there is a dense packing of atoms with a coordination number of 12. It takes a lot of energy to destroy it.
The crystal lattice of the stable a-modification is formed by diatomic Ga 2 molecules bound together by van der Waals forces (cm. INTERMOLECULAR INTERACTION), bond length 0.244 nm.
The standard electrode potential of the Ga 3+ /Ga pair is –0.53V, Ga is in the electrochemical series up to hydrogen (cm. HYDROGEN).
In terms of chemical properties, gallium is similar to aluminum.
In air, Ga is covered with an oxide film, which prevents further oxidation. With arsenic (cm. ARSENIC), phosphorus (cm. PHOSPHORUS), antimony (cm. ANTIMONY) forms gallium arsenide, phosphide and antimonide, with sulfur (cm. SULFUR), selenium (cm. SELENIUM), tellurium (cm. TELLURIUM)- chalcogenides. When heated, Ga reacts with oxygen (cm. OXYGEN). With chlorine (cm. CHLORINE) and bromine (cm. BROMINE) gallium reacts at room temperature with iodine (cm. IOD)- when heated. Gallium halides form Ge 2 X 6 dimers.
Gallium forms polymeric hydrides:
4LiH + GaCl 3 = Li + 3LiCl.
The ion stability decreases in the series BH 4 – - AlH 4 – - GaH 4 – . Ion BH 4 - stable in aqueous solution, AlH 4 - and GaH 4 - quickly hydrolyze:
GaH 4 - + 4H 2 O \u003d Ga (OH) 3 + OH - + 4H 2
When heated under pressure, Ga reacts with water:
2Ga + 4H 2 O = 2GaOOH + 3H 2
With mineral acids, Ga slowly reacts with the release of hydrogen:
2Ga + 6HCl = 2GaCl 3 + 3H 2
Gallium dissolves in alkalis with the formation of hydroxogallates:
2Ga + 6H 2 O + 2NaOH = 2Na + 3H 2
Gallium oxide and hydroxide exhibit amphoteric properties, although their main properties are enhanced compared to Al:
Ga 2 O 3 + 6HCl \u003d 2GaCl 2,
Ga 2 O 3 + 2NaOH + 3H 2 O \u003d 2Na
Ga 2 O 3 + Na 2 CO 3 \u003d 2NaGaO 2 + CO 2
When a solution of any gallium salt is alkalized, gallium hydroxide of variable composition Ge 2 O 3 is released x H2O:
Ga (NO 3) 2 + 3NaOH \u003d Ga (OH) 3 Ї + 3NaNO 3
When Ga (OH) 3 and Ga 2 O 3 are dissolved in acids, aqua complexes 3+ are formed, therefore, gallium salts are isolated from aqueous solutions in the form of crystalline hydrates, for example, gallium chloride GaCl 3 6H 2 O, potassium gallium alum KGa (SO 4) 2 12H 2 O. Gallium aqua complexes in solutions are colorless.
Application
About 97% of the gallium produced by the industry is used to obtain compounds with semiconductor properties, for example, gallium arsenide GaAs. Gallium metal is used in radio electronics for "cold soldering" of ceramic and metal parts, for doping Ge and Si, and for obtaining optical mirrors. Ga can replace Hg in electric current rectifiers. The eutectic alloy of gallium with indium is used in the radiation circuits of reactors.
Features of circulation
Gallium is a low toxic element. Due to the low melting point, Ga ingots are recommended to be transported in polyethylene bags, which are poorly wetted by liquid gallium.

encyclopedic Dictionary. 2009 .

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    Metal, a simple body, the existence of which was foreseen by Mendeleev and which was discovered by Lecoq de Bouaubaudran. Dictionary of foreign words included in the Russian language. Chudinov A.N., 1910. GALLIUM is an indecomposable mineral, blue-white in color; solid,… … Dictionary of foreign words of the Russian language

    - (Gallium), Ga, chemical element of group III of the periodic system, atomic number 31, atomic mass 69.72; metal. Gallium was discovered by the French chemist P. Lecoq de Boisbaudran in 1875 ... Modern Encyclopedia

    Ga (lat. Gallium * a. gallium; n. Gallium; f. gallium; and. galio), chem. group III element periodic. Mendeleev systems, at. n. 31, at. m. 69.73. Consists of two stable isotopes 69Ga (61.2%) and 71Ga (38.8%). Predicted in 1870 by D. I. ... ... Geological Encyclopedia

    gallium- I, m. gallium m. From lat. the name of France, where it was discovered in 1875 by the chemist Lecoq de Boisbaudran. ES. Chemical element, soft fusible silvery-white metal; used instead of mercury for the manufacture of pressure gauges and high-temperature ... ... Historical Dictionary of Gallicisms of the Russian Language

    Gallium- (Gallium), Ga, chemical element of group III of the periodic system, atomic number 31, atomic mass 69.72; metal. Gallium was discovered by the French chemist P. Lecoq de Boisbaudran in 1875. ... Illustrated Encyclopedic Dictionary