Strength, attraction, power - this is how the people of ancient Greece interpreted the word "magnes". There was a city in this country called Magnesia. Near these settlements, magnetic iron ore was mined, which, as you know, has the power to attract metal objects.

But, metal magnesium named not in honor of the iron-containing rock, but in honor of the powder "white magnesia". The Greeks obtained it from a mineral that was also available near the ancient settlement. After calcining, the stone turned into a white powder - magnesium oxide... The Greeks did not know that the substance was metal, but they noticed the medicinal properties of the composition. He helped with diseases of the liver, kidneys, played the role of a laxative.

The drug did not go out of use for centuries and, in 1808, Gefri Davy isolated an unknown metal from it during experiments. Without hesitation, a scientist from England named the open element magnesia. So it is still called in Europe. Russians call metal magnesium thanks to the textbook Hermann Hess. Despite his German roots, the chemist is Russian. In 1831 he translated a Western textbook. The scientist transformed the word "magnesia" into "magnesium". So in domestic science the element received a special name.

In the periodic table of chemical elements Magnesium takes 12th position. It is located in the main subgroup of the group at number two. Element is white with silvery reflections. This color is typical for all alkaline earth metals, to which, along with strontium, radium and barium, magnesium also belongs. He is a "fluff" among metals. For example, iron and copper are almost 5 times heavier. Even lightweight aluminum will outweigh element # 12 on the bowl.

The ease of magnesium plays into the hands of aircraft designers and manufacturers. They do not have to be heavy in order to have good flying properties. However, you cannot use pure metal # 12 for the same aircraft. He's too soft, pliable.

Have to make manganese alloys, aluminum or. They give manganese strength without making it heavier. The mixtures are mainly used for the production of plating for "iron birds". The first aircraft based on magnesium alloys, by the way, was the work of domestic aircraft technicians. The vessel was created back in 1934 and named "Sergo Ordzhonekidze".

Element magnesium very problematic to remelt. It only needs 650 degrees Celsius. However, already at 550, the metal flares up and dissolves in the atmosphere. The emitted flame is very effective, so the metal has found application in the pyrotechnic industry.

Not a single fireworks or sparkler is complete without it. If magnesium is stored at home, it is best not to spill bleach next to it. In the presence of chlorine, the 12th element ignites even at a temperature of 25 degrees.

The combustion products of magnesium are ultraviolet rays and heat. Even a few grams of metal is enough to boil 200 milliliters of water. This is enough to drink tea. Scientists from Warsaw decided to "force" the element to heat food. Physicists have built in canned food cans magnesium tape... When the container is opened, the insert ignites, heating the contents of the can. Here's a ready-made lunch.

Self-heating cans have been around for thousands of years. Magnesium deposits in the bowels of the earth compete with the reserves of only 7 elements. More only silicon, oxygen, iron, aluminum and calcium. Metal No. 12 is part of two hundred minerals. The element is also extracted from carnallite on an industrial scale.

Magnesium is also the main constituent of magma, the incandescent layer between the planet's core and its surface. In the seawater of element number 12, there are 4 kilograms for each cubic meter.

If the water of the oceans is mixed with shells, crushed into powder, you get magnesium chloride... Pure metal can be isolated from it by electrolysis. But, they used this method only during the Second World War. We extracted about 100 thousand tons of element 12 and calmed down, because it is troublesome to process the resources of the seas in huge tanks.

For metallurgy, one of the main consumers of magnesium, its reserves in the earth's crust are also sufficient. The metal is required in the production of almost all alloys. Element No. 12 reduces the oxygen content in them, which sharply degrades the product quality. Getting magnesium to become part of an alloy is not easy. Due to its lightness, it does not sink in other metals. Due to the "explosive reaction" to air, it flares up on the surface of mixtures.

Metallurgists have to press the capricious metal into briquettes, place sinkers inside them and, only after that, lower them into the composition for remelting.

Magnesium lightness attracted and. They add the element to precious alloys to lighten the pieces. This is very useful if the decoration is voluminous, of impressive dimensions. Not everyone wants to wear an incredible weight for jewelry. Magnesium comes to the rescue.

But, if jewelry making without magnesium is possible, then life is not. Metal magnesium is a part of chlorofill. He is a part of vegetation, a substance responsible for photosynthesis. That is, without element 12, the process of converting carbon dioxide into oxygen would be impossible. The atmosphere of the planet would be different, so that humanity on Earth would hardly have appeared without magnesium on it.

This metal helps the human heart to beat, not only by supplying it with oxygen. Magnesium is essential for the stable work of the heart muscle. According to statistics, heart attacks occur mainly in people who lack element 12 in their bodies. Therefore, it does not hurt to eat pumpkin seeds, bran, drink cocoa and tea. These foods contain the most magnesium.

Magnesium - an element of the main subgroup of the second group, the third period of the periodic system of chemical elements of DI Mendeleev, with atomic number 12. It is designated by the symbol Mg (Latin Magnesium). The simple substance magnesium (CAS number: 7439-95-4) is a light, malleable silver-white metal.

1 element of the periodic table In 1695, salt was isolated from the mineral water of the Epsom spring in England, which had a bitter taste and laxative effect. Pharmacists called it bitter salt, and also English or epsom salt. Mineral epsomite has the composition MgSO4 · 7H2O. The Latin name for the element comes from the name of the ancient city of Magnesia in Asia Minor, in the vicinity of which there are deposits of the mineral magnesite.

In 1792, Anton von Ruprecht received a new metal, which he named austria, reduction with coal from white magnesia. Later it was found that "austria" is magnesium of an extremely low degree of purity, since the starting material was heavily contaminated with iron.

Discovery history

In 1695, salt was isolated from the mineral water of the Epsom spring in England, which had a bitter taste and laxative effect. Pharmacists called it bitter salt, and Epsom or Epsom salt. Mineral epsomite has the composition MgSO4 · 7H2O. The Latin name for the element comes from the name of the ancient city of Magnesia in Asia Minor, in the vicinity of which there are deposits of the mineral magnesite.
In 1792, Anton von Ruprecht received a new metal, which he named austria, reduction with coal from white magnesia. Later it was found that "austria" is magnesium of an extremely low purity, since the starting material was heavily contaminated with iron.
It was first isolated in its pure form by Sir Humphrey Davy in 1808 by distilling mercury from magnesium amalgam, which he obtained by electrolysis of a semi-liquid mixture of magnesium oxide and mercury.

Being in nature

Clark magnesium (wt.) - 1.95% (19.5 kg / t). It is one of the most common elements of the earth's crust. Large amounts of magnesium are found in seawater. The main types of magnesium raw materials are:

sea \u200b\u200bwater - (Mg 0.12-0.13%),
carnallite - MgCl2. KCl. 6H2O (Mg 8.7%),
bischofite - MgCl2. 6H2O (Mg 11.9%),
kieserite - MgSO4. H2O (Mg 17.6%),
epsomite - MgSO4. 7H2O (Mg 16.3%),
kainite - KCl. MgSO4. 3H2O (Mg 9.8%),
magnesite - MgCO3 (Mg 28.7%),
dolomite - CaCO3 MgCO3 (Mg 13.1%),
brucite - Mg (OH) 2 (Mg 41.6%).
Magnesian salts are found in large quantities in the salt deposits of self-deposited lakes. Deposits of fossil carnallite salts of sedimentary origin are known in many countries.

Magnesite is formed mainly in hydrothermal conditions and belongs to medium-temperature hydrothermal deposits. Dolomite is also an important magnesium raw material. Dolomite deposits are widespread, their reserves are huge. They are associated with carbonate strata, and most of them are of Precambrian or Permian age. Dolomite deposits are formed by sedimentary means, but can also arise when limestones are affected by hydrothermal solutions, groundwater or surface waters.

MAGNESIUM CONSUMPTION TABLE

Floor	Age	Daily intake of magnesium, mg / day	Upper acceptable limit, mg / day
Babies	from 0 to 6 months	30	Indefined
Babies	from 7 to 12 months	75	Indefined
Children	from 1 to 3 years	80	145
Children	from 4 to 8 years old	130	240
Children	from 9 to 13 years old	240	590
Girls	from 14 to 18 years old	360	710
Young men	from 14 to 18 years old	410	760
Men	from 19 to 30 years old	400	750
Men	31 and older	420	770
Women	from 19 to 30 years old	310	660
Women	31 and older	320	670
Pregnant women	from 14 to 18 years old	400	750
Pregnant women	from 19 to 30 years old	350	700
Pregnant women	31 and older	360	710
Breastfeeding women	from 14 to 18 years old	360	710
Breastfeeding women	from 19 to 30 years old	310	660
Breastfeeding women	31 and older	320	670

Appearance of a simple substance

Malleable, silvery white metal

Atom properties Name, symbol, number

Magnesium (Mg), 12

Atomic mass
(molar mass)

[comm 1] a. e.m. (g / mol)

Electronic configuration Atom radius Chemical properties Covalent radius Ion radius Electronegativity

1.31 (Pauling scale)

Electrode potential Oxidation states Ionization energy
(first electron)

737.3 (7.64) kJ / mol (eV)

Thermodynamic properties of a simple substance Density (at n.a.)

1,738 g / cm³

The melting temperature

650 ° C (923 K)

Boiling temperature

1090 ° C (1363 K)

Ud. heat of fusion

9.20 kJ / mol

Ud. heat of vaporization

131.8 kJ / mol

Molar heat capacity

24.90 J / (K mol)

Molar volume

14.0 cm³ / mol

The crystal lattice of a simple substance Lattice structure

hexagonal

Lattice parameters

a\u003d 0.32029 nm, c\u003d 0.52000 nm

C / a ratio Debye temperature Other characteristics Thermal conductivity

Magnesium compounds have been known to man for a long time. The Latin name for the element comes from the name of the ancient city of Magnesia in Asia Minor, in the vicinity of which there are deposits of the mineral magnesite. Metallic magnesium was first obtained in 1808 by the English chemist G. Davy. The magnesium obtained by Davy was rather dirty, pure metallic magnesium was obtained for the first time in 1828 by the French chemist A. Bussy.

Being in nature, getting:

Magnesium is one of the ten most abundant elements in the earth's crust. It contains 2.35% magnesium by weight. Due to its high chemical activity, magnesium is not found in free form, but is a part of many minerals - silicates, aluminosilicates, carbonates, chlorides, sulfates, etc. Thus, magnesium is contained in the widespread silicates olivine (Mg, Fe) 2 and serpentine Mg 6 (OH) 8.
Of great practical importance are such magnesium-containing minerals as asbestos, magnesite, dolomite MgCO 3 CaCO 3, bischofite MgCl 2 6H 2 O, carnallite KCl MgCl 2 6H 2 O, epsomite MgSO 4 7H 2 O, kainite KCl MgSO 4 3H 2 O, astrakhanite Na 2 SO 4 MgSO 4 4H 2 O, etc.
Magnesium is found in seawater (4% Mg in dry residue), in natural brines, in many underground waters.
The usual industrial method for producing metallic magnesium is the electrolysis of a melt mixture of anhydrous magnesium chlorides MgCl 2, sodium NaCl and potassium KCl. In this melt, magnesium chloride undergoes electrochemical reduction.
Another way to obtain magnesium is thermal. In this case, coke or silicon is used to reduce magnesium oxide at a high temperature. The use of silicon makes it possible to obtain magnesium from raw materials such as dolomite CaCO 3 · MgCO 3 without preliminary separation of magnesium and calcium. With the participation of dolomite, reactions occur:
CaCO 3 MgCO 3 \u003d CaO + MgO + 2CO 2, 2MgO + 2CaO + Si \u003d Ca 2 SiO 4 + 2Mg.
To obtain magnesium, not only mineral raw materials are used, but also sea water. The purity of refined magnesium reaches 99.999% and higher.

Physical properties:

Magnesium is a silvery-white shiny metal, relatively soft and ductile, a good conductor of heat and electricity. Density of magnesium ??? g / cm 3, it is almost 5 times lighter than copper, 4.5 times lighter than iron; even aluminum is 1.5 times heavier than magnesium. Melting point ??? ° C, boiling point ??? ° C.

Chemical properties:

Relation to air and oxygen under normal conditions: ...
When heating: ...
Magnesium almost does not interact with cold water, but when heated it decomposes with the release of hydrogen. In this respect, it occupies an intermediate position between beryllium, which does not react with water at all, and calcium, which easily interacts with it.
In the electrochemical series of voltages, magnesium is much to the left of hydrogen and actively reacts with dilute acids to form salts. Magnesium has some peculiarities in these reactions. It does not dissolve in hydrofluoric, concentrated sulfuric acid and in a mixture of sulfuric and nitric acids, which dissolves other metals almost as effectively as "aqua regia" (a mixture of HCl and HNO 3). Does not interact with alkali solutions.

The most important connections:

Magnesium oxide, MgO: ???.
When stored in air, magnesium oxide gradually absorbs moisture and CO 2, transforming into Mg (OH) 2 and MgCO 3
Magnesium peroxide, MgO 2: obtained by reacting freshly precipitated Mg (OH) 2 with 30% H 2 O 2. A colorless microcrystalline substance that is slightly soluble in water and gradually decomposes when stored in air.
Magnesium hydroxide, Mg (OH) 2: white, very slightly soluble in water. In addition to acids, it is soluble in solutions of ammonium salts (which is important for analytical chemistry). Found in nature (brucite mineral).
Magnesium salts... Most magnesium salts are highly soluble in water. The solutions contain colorless Mg 2+ ions, which impart a bitter taste to the liquid. They are noticeably hydrolyzed with water only when the solution is heated.
Most of the salts are released from solutions in the form of crystalline hydrates (eg MgCl 2 * 6H 2 O, MgSO 4 * 7H 2 O). MgSO 4 * 7H 2 O forms a mineral in nature " epsom salt".
When the crystalline hydrates of halide salts are heated, basic salts that are hardly soluble in water are formed.
Poorly soluble magnesium salts include MgF 2 (solubility 0.08 g / l), magnesium carbonate. The latter can be obtained by an exchange reaction only when a large excess of CO 2 is present in the solution, otherwise basic salts precipitate. An example of such a salt is " white magnesia"- basic salt of approximate composition 3MgCO 3 * Mg (OH) 2 * 3H 2 O

Application:

The main part of the mined magnesium is used to obtain various light alloys. The composition of these alloys, in addition to magnesium, includes, as a rule, aluminum, zinc, zirconium. Such alloys are strong enough and find application in aircraft construction, instrument making and for other purposes.
To protect water heaters and heating boilers against corrosion, magnesium anodes are used, which are steel rods with a layer of magnesium alloy applied to them. In this case, the anode itself is destroyed, and not the walls of the water heater (protective protection).
The high chemical activity of metallic magnesium makes it possible to use it in the magnesium-thermal production of metals such as titanium, zirconium, vanadium, uranium, etc. In this case, magnesium reacts with the oxide or fluoride of the resulting metal, for example:
2Mg + TiO 2 \u003d 2MgO + Ti or 2Mg + UF 4 \u003d 2MgF 2 + U.
Many magnesium compounds are widely used, especially its oxide, carbonate and sulfate. Thus, bitter salt is used in the textile and paper industry, as well as in medicine.

In the human body, the amount of magnesium is only a few tenths or hundredths of a percent, but it plays an important role in vital processes. Magnesium enhances the processes of carbohydrate metabolism in muscles, regulates calcium metabolism; therefore, due to a lack of magnesium, osteoporosis and inflammatory-dystrophic diseases of the musculoskeletal system develop.
An insufficient amount of magnesium in the blood is a sign of overwork or stress. It has been proven that a lack of magnesium in the body contributes to the disease of myocardial infarction. It enters the body with food, but less than 40% of magnesium is absorbed, since its compounds are poorly absorbed by the intestines.

The main producer of this metal in the world is China, which has "monopolized" the world market. In 2007, the production of Chinese magnesium reached 260 thousand tons. In Russia, production is concentrated in the Perm Territory (25 thousand tons / year). In 2004, Russian Magnesium OJSC was established to build a magnesium production plant in Asbest (Sverdlovsk region), but the project is currently frozen.

Aliullov Andrey
KhF Tyumen State University, 581 group, 2011

Today, not even every adult will remember why we can unequivocally answer the question: magnesium metal or non-metal? Magnesium - referred to as alkaline earth metals! A quick glance at the electronic configuration 1s22s22p63s2 of the neutral atom of this substance will help to recall this. Considering the specificity of metals to have from 1 to 3 free electrons at the external energy level, they look at this parameter for Mg as well. It is not difficult to see that the configuration contains 2 free electrons.

The general metallic properties of magnesium are similar to those of other substances of this type. They are usually hard, but ductile (unlike brittle non-metals). They have a specific shine. Mg tends to tarnish in air due to the fact that it is covered with a protective oxygen film. Magnesium powder is highly flammable, just bring a lighted match. The color of magnesium burning is bright white. One of the reasons why this metal was originally used in photography. Mg was applied to a special tape and set on fire. During combustion, MgO is formed; also, when the process proceeds in air, magnesium nitride is released with the release of a large amount of heat.

This is what metallic magnesium looks like

Features of Mg as an element of the periodic table

The chemical properties of magnesium are in many ways somewhere between and calcium. First of all, this manifests itself in interaction with water. The first does not react with it at all, while the second dissolves in it. Mg interacts weakly with heated water. But when interacting with water vapor (from 400 degrees Celsius), a reaction occurs Mg + H2O \u003d MgO + H2, in which the metal dissolves with the active evolution of hydrogen.

Video - the chemical properties of magnesium:

A slightly different reaction occurs with water vapor: Mg + 2H2O \u003d Mg (OH) 2 + H2. Moreover, free hydrogen is eventually absorbed by magnesium MgH3. As a result, if the metal melts in a humid environment, as it solidifies, hydrogen almost completely disappears.

Magnesium properties: interact with water at high temperatures and burns in the presence of carbon dioxide in the atmosphere, - make it difficult to extinguish fires with the participation of Mg. They cannot be extinguished with water. According to the instructions, use powder fire extinguishers and sand. It is also possible to use Si oxides, with which magnesium reacts, but the amount of heat generated is much lower.

It should also be noted that despite the actual insolubility of Mg (OH) 2 in water, the phenolphthalein solution turns pink in its presence.

Magnesium in the periodic table

Magnesium metal is resistant to caustic alkalis, soda, kerosene, gasoline, mineral oils. The ability of this element to take away oxygen and chlorine is used to restore pure substances. For example, bromine or titanium.

For the synthesis of different classes of organic compounds, the property of magnesium is used to interact with halogens. Usually it is Cl, Br, I, with fluorine Mg forms a protective film, which is why their combination is rarely used for the synthesis of Grignard reagents. The latter are most often formed on the basis of the RMgHal formula, where R is an organic radical and Hal is one of the listed halogens.

What physical properties does magnesium metal have?

Video: Magnesium is a metal that burns

The lightness of the element reflects the density, which is 1.74 g / cm3. Only calcium and alkali metals have less. The physical properties of magnesium can be briefly described by standard encyclopedic parameters:

• Melting point - 651 ° C;
• Boiling point - 1107 ° C;
• Thermal conductivity - 0.376 cal / (cm · s · deg) is quite high, comparable to that demonstrated by beryllium and tungsten;
• Heat capacity at T melting - 0.3 cal / deg;
• Specific heat increases to T melting and decreases upon reaching it;
• Shrinkage when changing states (liquid - solid) - 3.97-4.2%;
• Specific electrical resistance at room temperature - 0.047 ohm · mm2 / m.

This element of Mendeleev's periodic table referred to as alkaline earth metals... However, this statement is not always true, since the chemical properties bring this element closer to aluminum-like substances.

MgO oxides are referred to as white refractory substances, they are called burnt magnesia and are used in the manufacture of building materials. Magnesium metal salts are formed when a substance interacts with acids. The most famous of them is MgCO3. Used by metallurgists to free alloys from slags, called magnesium carbonate. Another salt, MgSO4, is known as bitter or Epsom. Chemists call it magnesium sulfate. Mg and Ca affect water hardness. The high concentration of these substances in H2O prevents detergents from foaming.

In order to answer in more detail what physical properties magnesium has, it is necessary to consider changes in its states and qualities as various thermal effects are applied to it: heating and cooling. So, for example, the density decreases by 6% at T - 600 0 С, having melted and completely drops to a value of 1.58 g / cm3.

Magnesium metal performance is very different at low and high temperatures. Some experimental results require explanation, some of them give quite predictable reactions.

The hexagonal lattice of the element has the following parameters:

• c \u003d 5.199 angstroms;
• a \u003d 3.202 angstroms.

When heated to 6270C, these distances increase, reaching the melting point, the lattice bonds are completely destroyed.

If we talk about the color of magnesium, it should be noted that in general, a silvery-white metal can look like black charred with an inherent luster. In the latter case, we are talking about magnesium chips. Therefore, when determining "by eye" the type of material, it is still better to turn to chemical experiments if there is no spectral analyzer at hand.

A classic problem for schoolchildren considers a series of sodium - magnesium - aluminum, the metallic properties of which weaken from the first to the last element.

Interaction with various acids

For brevity, it's easier to consider a few experiments. For them, the following types of acids are taken:

1. Salt.
2. Nitrogen.
3. Sulfuric (diluted and not).

In the first case, almost instantaneous dissolution is observed, accompanied by bubbles of white gases and a pungent smell of chlorine. The container in which the reaction took place is heated.

A piece of magnesium does not sink in nitric acid. Brown gas accumulates above the surface of the liquid, heat is released. It is sometimes said that the acid "boiled", surrounding the pieces of magnesium.

The third case must be considered as two particular ones. In undiluted sulfuric acid, the reaction is slow. If you use a solution with a small amount of water, magnesium floats on the surface just like with nitric acid. In this case, a subtle reaction occurs with the release of white gas bubbles.

Getting magnesium and history of discovery

The high reactivity prevents metallic magnesium from being found in its pure form. The sources of materials for its extraction are magnesium ores or compounds of salts contained in the waters of the seas, oceans, and underground. It is asbestos, olivine, serpentine, magnesite, dolomite and other minerals that have been known to the world for a long time. The name of the substance has the same roots as the name of the city in Asia Minor - Magnesia. Only in 1808, the English chemist G. Davy obtained a metallic precipitate by electrolysis, which he called magnesium.

However, it was not pure metal. It took the world of scientists another 20 years to obtain exactly Mg in the form that presented it in the periodic table. The discovery of pure magnesium metal was made by the French chemist A. Bussy in 1828.

The very same electrolysis method formed the basis for the classical methods of obtaining this element in its pure form. Deposits of magnesium-containing ores are mainly used for production. The most famous for the citizens of Russia is in the Urals - Satkinskoe. But there are a number of other deposits in Siberia, as well as in India, China, Korea, some European countries and South America.

In production, to obtain metallic magnesium, a melt of dehydrated chlorides is used: magnesium, sodium and potassium. When using continuous electrolysis, recovery occurs according to the following formula:

MgCl2 (electrolysis) \u003d Mg + Cl2.

The possibility of implementing the processes described below, magnesium metal with a price per kg remains in demand. The refined metal is taken out of the electrolysis bath by pouring magnesium-containing raw materials onto the replacement. In this way, the metal is practically free from impurities. The share of the latter is no more than 0.1%. If there is a need to reduce this indicator, the not yet solidified metal is refined to obtain a purity of 99.999% or more.

There is another way to obtain magnesium - this is the reduction of MgO oxide with addition at a high temperature. Dolomite is used as an alternative, this method does not require preliminary separation of calcium. The oxides CaO and MgO obtained as a result of the reaction are mixed with silicon. At the exit they have the purest magnesium and Ca2SiO4. For this method, it is permissible to use minerals or sea water.

Magnesium use

Has a wide range from medicine to aircraft construction. The physical properties of magnesium metal, namely its lightness (density), makes this element indispensable in alloys. Most often these are compounds with zinc, zirconium or aluminum. With the obvious lightness of such alloys, their strength is observed.

It should be noted once again that the active chemical properties of magnesium metal make it possible to use Ti, U, V, Zr, and others in the reduction processes. The ability to scavenge oxygen or react with fluorine is commonly used. The output is pure metals plus Mg oxides or fluorides.

In magnesium, the metallic properties are expressed in a special way: it is well cut, due to which the chips of this element are easily obtained. But in its pure form, the element is practically not used as a structural metal, but its alloys are.

A little has already been said about the properties of the latter. But it should be noted that magnesium compounds with a small amount of Al, Zn, Mn, Be, Ti and rare earth elements have better mechanical properties than pure Mg metal. They are more resistant to corrosion, stronger, more resistant.

The main areas of application of magnesium in alloys: these are structural materials in the structure of aircraft, cars, railway transport. Another area is the synthesis of organic substances, discussed earlier.

Magnesium non-metal is better known as Mg fluoride and is actively used in optics for the production of lenses. The latter are transparent, plastic, and durable. The materials are better known as synthetic single crystals. In industry, silicon is sometimes used, as well as gold, silver plating.

In steelmaking, magnesium scrap is used for its ability to attract oxygen. It acts as a deoxidizer. Due to this, alloy steel alloys have greater corrosion resistance. Therefore, magnesium is often involved in non-ferrous casting. Anodes are made from it.

Other "non-metallic" magnesium compounds, for example, its sulfate, are also in great demand. Known solutions for injections or suspensions, the latter can be prepared by the patient at home on his own. Taking magnesium reduces the risk of hypertension in smokers.

Magnesium is also used in agriculture, almost all types of soil where there is vegetation contain this element. The participation of Mg in plant photosynthesis should also be noted.

Magnesium metal price per kilogram

Not all locations accept magnesium. For those who accept, there is only one category of this metal - lumpy magnesium scrap (more precisely, it is not even magnesium in its pure form, but alloys in which it is contained, but in the points it is designated as magnesium scrap), its cost (average) is:

Lump magnesium scrap — 38 rubles per kilogram .

In household use, magnesium scrap is various hangers, doorknobs. Scrap magnesium can be found in the form of old cylinder blocks from engines, car seats, dashboards, clutch and gearbox housings, pedals, as well as the engine sump, cylinder head cover, and intake manifold.

Scrap magnesium should not be confused with.

The wide range of applications of this element in metallurgy, medicine, agro-industrial complex makes it interesting as a secondary raw material.

However, it is quite rare to see ads with a desire to buy magnesium with a price per kg of scrap. Alloys and Mg sulfate powder are more often in demand. But this does not prevent the exchange from evaluating magnesium metal, the price of which depends on the release of a pure product. Periodically, output decreases, then the tabloids show an increase in the cost of the product.

At reception points magnesium scrap and the price for it may depend on the conditions under which the purchase / sale takes place - the price may vary slightly and on its volume.

Interest in the material is fueled by its high refractoriness. Due to this property, Mg participates in the production of linings and crucibles for metallurgical furnaces. Apparently, therefore, the announcements: I will buy scrap magnesium, do not lose their relevance - see also.

Magnesium is a light, silvery-white metal, shiny, but tarnishing in air due to the formation of a protective oxide film on its surface. The chemical formula of magnesium is Mg. 12 - atomic number of magnesium in the periodic table of chemical elements of D.I. Mendeleev.

Magnesium is quite abundant in the earth's crust. Only oxygen, silicon, aluminum, iron and calcium are ahead of magnesium in this regard. In nature, it occurs in the form of compounds. The most important minerals containing magnesium - magnesite MgCO 3 and the double salt dolomite CaMg 2. Huge reserves of magnesium are found in the seas and oceans in the form of MgCl 2. Science knows about 1500 minerals. And nearly 200 of them contain magnesium.

Getting magnesium

How was magnesium discovered?

In 1695, the English physician Crewe analyzed mineral water from a spring near the city of Epsom. Upon evaporation of this water, a white salt with a bitter taste was formed on the walls of the vessel. This salt had medicinal properties. The pharmacists called this Epsonian or Epsonian salt. Later, the salt was named white magnesia because of its similarity to the white powder, which was obtained by calcining a mineral found near the Greek city of Magnesia.

Magnesium metal was first obtained in 1808 by the British chemist Humphrey Davy. Davy electrolyzed a mixture of white magnesia and mercury oxide. As a result, he received an alloy of mercury and an unknown metal. After isolating the metal, Davy suggested calling it magnesium. But Davy's magnesium contained impurities. Pure, without impurities, magnesium was obtained only in 1829 by the French chemist Antoine Bussy.

Chemical properties of magnesium

Magnesium is an active metal. And like all active metals, it burns well. Under normal conditions, its surface is protected by an oxide film. But when heated to 600 degrees, the film collapses, and magnesium reacts with oxygen. The combustion product of magnesium is magnesium oxide, white powder.

2Mg + O 2 \u003d 2MgO

Burning gives off a lot of heat and light. Moreover, according to its spectral analysis, the light from burning magnesium is almost the same as sunlight. This property was used by the first photographers over 100 years ago. Combustion of magnesium powder with additives of potassium permanganate or barium nitrate illuminated the subject of photography, which made it possible to take clear pictures in a closed room where lighting was insufficient.

Magnesium reacts with water only when heated. As a result of this reaction, hydrogen is released.

Mg + 2H 2 O \u003d Mg (OH) 2 + H 2

Magnesium burns in an environment of carbon dioxide.

2Mg + C O 2 \u003d 2MgO + C

Magnesium interacts with halogens at room temperature.

Mg + Br 2 \u003d MgBr 2

Magnesium reacts with sulfur only when heated, forming magnesium sulfide.

Mg + S \u003d MgS

Magnesium does not react with alkalis.

Getting magnesium

Metallic magnesium is obtained by electrothermal or electrolytic methods.

In the first case, magnesite or dolomite in the reaction apparatus is calcined. The result is magnesium oxide MgO. The magnesium oxide is then reduced with aluminum, silicon or coal. This is how pure magnesium is obtained.

But the main industrial method for obtaining magnesium is electrolytic. In special baths-electrolysers there is a melt of magnesium chloride MgCl2. As a result of electrolysis, magnesium is released on the iron cathode, and chlorine ions are collected on the graphite anode. The molten magnesium is collected and poured into molds. Then magnesium is purified from impurities.

Magnesium use

Magnesium's ability to readily interact with oxygen allows it to be used in steelmaking to remove oxygen dissolved in molten metals. Magnesium powder is used in rocketry as a high-calorie fuel. Highly purified magnesium is used in the manufacture of semiconductors.

Magnesium is the lightest of the metals. It is four times lighter than iron and one and a half times lighter than aluminum. Pure magnesium is soft and fragile. Technical constructions cannot be made of it. But the mechanical strength of magnesium is significantly increased if zinc, aluminum or manganese are added to it. The additives are added in small amounts so as not to increase the specific gravity of magnesium. Unfortunately, these alloys lose their strength when heated. But if you add zinc, copper, silver, beryllium, thorium, zirconium, titanium to them, then they retain their mechanical strength even when the temperature rises. Magnesium alloy cases can be found in mobile phones, camcorders, and laptops. In addition, magnesium alloy parts absorb vibration 100 times better than aluminum and 20 times better than alloy steel. Therefore, they are widely used in aviation, automotive and other fields of technology.