What is liquid tin

Do-it-yourself liquid tin - Metalist's Handbook

Tin chloride (SnCl2) is a white powder, a strong reducing agent, a weak oxidizing agent. So, this video shows a method for producing tin chloride at home.

In order to obtain it you will need 1 - laboratory beaker, 2 - a piece of Soviet or modern tin, 3 - pure hydrochloric acid, 4 - electric stove. To begin, place your tin in a bowl, fill it with concentrated hydrochloric acid and place it on the tile.

I don’t recommend adding water, as you will get a weak solution and when it cools, most of your tin will precipitate into white fluffy flakes, so we don’t add water. Next, bring the solution to a gentle boil and boil for 1.5 – 2 hours maximum.

You will notice that your solution will turn black, don’t worry, it’s not dissolved tin, as soon as you remove it from the tile, within five minutes the solution will become transparent. Upon completion, let the solution cool, and then pour it into a glass container for storage along with the dark sediment and white flakes.

These white flakes are nothing more than tin chloride, tin salt SnCl2, and the dark precipitate is undissolved metallic tin, over time it will dissolve in the solution, and only white flakes will remain.

It is important to know that you do not need to make an exact ratio to make tin chloride, just take 200 - 300 milliliters of hydrochloric acid and a piece of tin that will not completely dissolve during the boiling period. Whether your tin is clean or dirty doesn’t matter either, the main thing is that it exists at all.

At the end of the video, I showed the reaction with tin chloride to determine gold in solution. In the presence of gold ions, a purple-brown spot of the adsorption compound of gold and tin acid appears. Stannic chloride is a very sensitive reagent that can detect the presence of gold in amounts up to 10 parts per billion. Tin chloride also perfectly reduces palladium from a solution of its salt.

The work “Making tin chloride SnCl2” created by the author named Maximov Ro, is published under the terms of the Creative Commons “Attribution” 4.0 International license.Maximov Ro, published under the terms of the Creative Commons “Attribution” 4.0 International license .

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Tin chloride SnCl2 - obtaining How to choose tin Gold test

How and from what to make tin chloride at home with your own hands? Where can I get tin chloride? How to choose tin? In this video, I will first select a suitable solder that has a higher tin content.

Source: https://ssk2121.com/zhidkoe-olovo-svoimi-rukami/

Liquid tin application

Today, tin is a common metal. However, in centuries it was quite rare and valuable, so Russia bought it from other countries. From this metal, Russian craftsmen created dishes with relief patterns, since soft, pliable tin could easily be processed with a chisel. After casting the product, the master decorated it with intricate patterns or an engraved inscription. Today, the Moscow Historical Museum has various examples of tin utensils that have been preserved from ancient times.

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WATCH THE VIDEO ON THE TOPIC: Chemical tinning 2

Everything you need to know about liquid tin, making your own solution

Tin is a chemically stable element. In a humid air environment, tin does not oxidize; it is characterized by a weak reaction with solutions of sulfuric, hydrochloric, and nitric acids. Its corrosion products are safe for humans. Coatings containing tin are plastic, withstand mechanical stress, and have protective properties.

Tinning is a technology for applying a thin layer of tin to the surface of products and parts. Tinning performs two functions:. Tinning is especially important for copper wires. Copper is characterized by rapid oxidation in air, which causes contact failure.

And this, in turn, leads to overheating and fire of the electrical wiring. Therefore, before soldering, the stripped wire strands are tinned. The application of protective metal coatings, including tin, is used in instrument and mechanical engineering. Information about the tinning operation is reflected in the part drawing.

The rules for indicating information on the thickness of the coating and tinning technology in the drawing are regulated by GOSTs: Tinning technology is implemented by melting solder, wetting the surface with solder and its further crystallization on the surface.

According to GOST, solder should be understood as a material with a lower melting point compared to the material from which the part is made. Tinning of copper, aluminum and steel is carried out with tin. For reference, the table shows the melting points of these metals. The process is based on the use of electric current and the occurrence of electrochemical reactions.

Tinning occurs by immersing parts in a bath of alkaline or acidic electrolyte. The main disadvantage is the high cost due to the consumption of electrical current. This process requires special equipment and highly qualified performers. Tinning using an electrolyte is associated with the complexity of preparing the solution.

During the process, constant monitoring of the concentration of alkali or acid in the electrolyte, as well as the condition of the anodes and the surface of the bath, must be carried out. When performing certain works in radio and electrical engineering, it becomes necessary to tin the copper surfaces of the boards before soldering.

The simplest method is chemical tinning. This is galvanic technology. Its essence lies in the fact that during the electrochemical reaction, copper ions on the surface are replaced by tin ions from a tin-containing solution.

To carry out such tinning at home, you will need a soldering bath for tinning a tin. The baths are affordable, compact with a diameter of about 80 mm, a depth of mm, and a power of W.

They can be used to prepare copper circuit boards for soldering by immersing them in solder, for applying semi-solder to electronic components, and for dismantling radio-electronic elements.

Due to the fact that tin has different valence in these electrolytes, its deposition rates differ. In an alkaline electrolyte, tin is deposited twice as slowly as in an acidic one.

Acidic electrolytes must contain surfactant surfactants. It can be glue, phenol or gelatin. If a surfactant is not added, then the tin on the cathode will precipitate in the form of crystals and will not form a continuous layer.

They must also contain enough free acid to inhibit the hydrolysis of tin salts.

Otherwise, basic tin salts or sparingly soluble hydrates will form. Additionally, to increase electrical conductivity, conductive salts must be introduced into the solution, for example, in a sulfuric acid electrolyte - this is sodium sulfate. If all these requirements are taken into account, the dissipative ability of an acidic electrolyte can be increased.

Alkaline electrolytes have better dissipation ability. It is advisable to use them for tinning small parts and parts of complex shapes. There are many ways to prepare alkaline solutions.

An electrolyte obtained from sodium stannate salt is considered easy to prepare. It does not contain chlorine ions, which reduces the risk of corrosion of the steel walls of the tinning bath. If problems arise during the operation of the baths, they can be easily eliminated by adjusting the properties of the electrolyte. It is prepared this way.

To 1 liter of distilled water add 20 g of tin chloride, 40 g of concentrated H 2 SO 4, then 80 g of thiourea to reduce turbidity. To prevent the formation of tin crystals on the surface, an additional 5 g of OS substance is dissolved in ml of water. Then the solutions are mixed. Let it sit for about three hours. Then a prepared and cleaned copper product, for example a board, is immersed in the solution.

After a shiny layer of tin appears on the surface, the solution is drained. The method of acid soldering of copper or aluminum wires of different sections is often used. In this case, soldering acid is used as a flux.

Thanks to it, a reliable connection between metal and solder is created, and deposits and oxides are removed from the surface of products. The most common acid is an aqueous solution of zinc chloride. Tinning by rubbing. Wires and small parts can be tinned using a soldering iron. Sequencing:. To heat the surface evenly, the soldering iron must be held so that it is adjacent to it with both the end and the working side edge.

If you need to apply poluda to large parts of a simple shape, then you can use another method: In case of poor preparation of the surface of the product, the thickness of the tin layer may vary, and in some places the layer may not be soldered. Then this place should be cleaned with a file, heated and tinning repeated.

The choice of technological equipment is determined by the method of tinning and soldering. Auxiliary and main equipment is used:. The quality of preparation of the surface of a part for tinning determines the strength of its adhesion to the coating. The preparation method depends on the condition of the surface.

Thus, tinning is an affordable way to protect metal products from corrosion or prepare them for soldering. Despite the cost and labor intensity, tinning operations can be performed at home. Tinning with tin.

Source: https://all-audio.pro/c4/prays-listi/zhidkoe-olovo-primenenie.php

Tin for soldering: melting point, solder composition

Everyone knows from school that tin with the chemical symbol “Sn” is used for soldering microcircuits and other radio components. The main requirement for this alloy is a low melting point.

This is because the solder must melt during the process, not the part being joined.

Pure tin with a melting temperature of 232 °C is quite suitable for these purposes, but in practice, pure tin is not actually used for soldering due to its high cost; alloys with lead and other metals are more often used.

Characteristics

Tin is indispensable in the production of electronic devices. Due to its properties, it is used for welding components in radio engineering. The alloy, called Eutectica, consists of lead (Pb), silver (Ag), copper (Cu) and nickel (Ni). Thanks to these additives, tin melts at different temperatures depending on the percentage of each of them.

Tin for soldering

Tin is soft and malleable, but very resistant to corrosion and does not form rust, has very good electrical conductivity and a relatively low melting point. All these characteristics make it indispensable for creating electronic devices.

The soldering process takes place in soft welding, which consists of combining two base elements by introducing a third element with a lower melting point into the base.

For example, soldering a copper circuit board pad to a capacitor leg uses molten tin, which melts at a much lower temperature than the base elements.

During the heating process, liquid tin, due to its capillary properties, is attracted to the base components, and then cools in soft soldering mode.

Eutectica alloy

Types of solders and fluxes

In our country, the POS brand of solder has become widespread - an alloy of tin Pb and lead Sn. Depending on the type, cadmium, nickel, copper, and other metals may be added to it. PIC is mainly produced in the form of rods, wires, balls and paste. Its chemical composition is strictly regulated by GOST 21930-76. In Russia, the following types of solder are widely used: POS18, POS30, POS50, POS90, which are soft alloys with a melting temperature of up to 300 degrees.

POS brands

POS-18

Solder is regulated by state standards; in addition to Pb (0.8%) and Sn (17-19%), it contains impurities of many metals. Regulatory authorities strictly ensure that the manufacturer limits the presence of toxic arsenic in the composition, which reduces the fluidity of the liquid alloy and increases fragility under conditions of alternating loads.

Composition of POS-18 impurities in percent:

• Cu - 0.1;
• Bi0 - 0.05;
• S—0.02;
• Fe - 0.02;
• Al, Ni, Zn - 0.002 each.

Technical data:

1. Density—10.3g/cm2.
2. The resistivity indicator is 0.200 µOhm•cm.
3. The Brinnel hardness index is 11 HB.
4. Thermal conductivity—0.37 kcal/cm*C*deg.
5. T at which the solder will melt solidus/liquidus—183/285 C.

Solder Advantages:

• Wide area of ​​alloy in liquid state;
• reduced content of impurities that cause brittleness;
• corrosion resistance of the soldering area, which is important for parts located in humid environments.

Disadvantages of POS-18:

• Special solder, not mass produced.
• The presence of harmful additives in the composition - Pb.

POS-18

POS-18 belongs to the universal alloys and is a substitute for antimony-free alloys; it is used:

• For the production of radio equipment;
• soldering low power printed circuit boards;
• car body repair in the form of tinning;
• connections of units made of copper-zinc alloys;
• repair of equipment in heating systems: boilers, radiators and other heating elements.

The price of POS-18 solder as of September 1, 2019 is from 710 rubles/kg.

POS-30

Solder is standardized by GOST 21930.76 / 21931.76 and belongs to soft alloys with a melting temperature of 256.0 C. Its properties are similar to grades with POS-40 and 50 and consists of Pb and Sn in a percentage ratio of 30:70, as well as other elements no more than 1 %. It differs from pure tin in its dark color and increased hardness of the alloy.

Solder POS-30

Composition of impurities in percentage:

• Sb - 0.1;
• Cu - 0.05;
• Bi0 - 0.2;
• S, As, Fe - 0.02 each;
• Al, Zn - 0.002 each.

Technical data:

1. Density - 9.72 g/cm2.
2. The resistivity indicator is 0.185 µOhm•cm.
3. The Brinell hardness index is 12 HB.
4. Thermal conductivity - 0.37 kcal/cm*C*deg.
5. Solidus/liquidus melting temperature - 183/256 C.

Solder Advantages:

• High fluidity;
• low melting temperature;
• low resistance allows you to work with small parts;
• high impact strength equal to pure tin;
• high scope of application, with the possibility of replacing expensive materials, for example, for soldering zinc or brass plates;
• Possibility of use for repairing household appliances.

The disadvantage of POS-30 is the presence of harmful additives in the composition - Pb.

The price of POS-30 as of September 1, 2019 is from 766 rubles/kg.

POS-50

It is produced in accordance with the requirements of GOST 21931.76, it is distinguished by a practically equal ratio of lead and tin.

Solder POS -50

Composition of POS-50 impurities in percent:

• Sb - 0.8;
• Cu - 0.1;
• Bi - 0.05;
• As - 0.05;
• S, Fe - 0.02 each;
• Ni, Al, Zn - 0.002 each.

Technical data:

1. Density - 8.87 g/cm2.
2. The resistivity indicator is 0.158 µOhm•cm.
3. The Brinell hardness index is 14 HB.
4. Thermal conductivity - 0.48 kcal/cm*C*deg.
5. Solidus/liquidus melting temperature - 183/209 C.

Solder Advantages:

• Good fluidity;
• good thermal and electrical conductivity;
• Possibility of use in wet environments;
• good ductility of the seam allows it to be used for products with increased requirements for tightness, for example, in measuring instruments and low-power PC circuits.

Disadvantages of POS-50:

• Ineffective when soldering thick products due to unstable heating; the presence of harmful additives in the composition - Pb;
• accelerated crystallization of the melt does not make it possible to use the alloy in manual soldering technology.

The price of POS-50 solder as of September 1, 2019 is from RUB 1,102.00/kg.

POS-90

The solder is characterized by low thermal conductivity and high hardness, which is explained by the high content of tin 90, the material is silver in color, which gives the resulting joints an aesthetic appeal.

Solder POS - 90

Composition of POS-90 impurities in percent:

• Sb - 0.1;
• Cu - 0.05;
• Bi - 0.2;
• As - 0.01;
• S, Fe - 0.02 each;
• Ni, Al, Zn - 0.002 each.

Technical data:

1. Density - 7.6 g/cm2.
2. The resistivity indicator is 0.120 µOhm•cm.
3. The Brinell hardness index is 15.4 HB.
4. Thermal conductivity - 0.13 kcal/cm*C*deg.
5. Solidus/liquidus melting temperature - 183/220 C.

Advantages of POS-90:

• Wide range of applications from household, medical to industrial sectors;
• good fluidity;
• high level of wettability in the liquid state;
• low melting temperature;
• good electrical conductivity;
• good tightness, the ability to use in water and gas environments; good plasticity of the seam allows it to be used for products with high
• sealing requirements, for example in measuring instruments and low-power PC circuits.

The disadvantages of POS-90 are the presence of harmful additives in the composition (lead).

The price of POS-90 solder as of September 1, 2019 is from RUB 1,778.00/kg.

What is the melting point

Tin, which is used in electronics, is usually a eutectic type, meaning that it is an alloy with a lower melting point for each of its constituent elements. So, if there is a 60% tin alloy (melting temperature - 232 C) and 40% lead (melting temperature - 327 C), then the total melting temperature of the alloy will be approximately 183 C.

Melting tin

The most common solder used in EU countries for electronic work is 63/37 SnPb. It is a eutectic alloy with a melting point of 183 C. The 60Sn alloy has a working range of 183-238. There is a lower temperature alloy Sn43Pb43Bi14, which has a melting point of 144-163.

Solder composition

The lead contained in the alloy is gradually being phased out in accordance with new EU directives (RoHS and WEEE) and is being replaced by solders consisting of tin-antimony alloys. Already today in the EU many stores do not sell it. Things are different here for now; it will probably be many years before lead solder in our country is replaced forever.

Important! Lead-free alloy has a higher melting point than lead alloy and uses more aggressive fluxes. This means that the soldering iron must be made for lead-free soldering to ensure the correct temperature of around 230 C. Lead-free solder is generally about 20-50% more expensive than lead solder.

How to choose the right one

The choice of solder depends on the type of work and purpose of the finished product, as well as on the conditions under which the product will be used.
Criteria to consider before choosing solder for soldering:

1. Soldering iron type.
2. Wire size. Diameters vary from centimeters or millimeters, the size of the wire depends on the work being performed.
3. The flux cleans the soldering area, making it easier for the solder to flow and therefore a perfect solder joint. Flux changes surface tension as it increases adhesive properties in the solder joint.
4. Before purchasing, you need to know at what temperature tin melts for soldering.
   Compound. The debate about whether to use lead or lead-free solder on PCBs is still ongoing. Despite debates caused by environmental and health concerns, many electrical technicians use lead.

Note! The expiration date and industry guidelines require its use within three years from the date of manufacture. The expiration date is indicated on the product and can be found in the store upon purchase. If you use expired solder paste, oxidation may occur on the solder surface, rendering the connection ineffective.

Usage

Experts give useful tips that are very helpful for novice radio amateurs to solder correctly:

1. Choose solder with a minimum lead content.
2. It is necessary to ensure the cleanliness of the soldering iron tip; it should not have dirty deposits.
3. For cleaning, use a file or sandpaper. After cleaning, the tip is tinned with rosin.
4. It is not recommended to hold the device at the solder point for a long time, since the parts being connected can suffer high temperature damage. To reduce the harmful effect of T on the part, it is held with tweezers, which will act as a heat sink.
5. The product is cleaned before soldering, and the contact contacts are additionally tinned to ensure excellent adhesion.

Soldering technology

Additional Information. When soldering, safety precautions must be taken. Always wear safety glasses to protect your eyes from flying drops of hot liquid solder. The tip of the soldering iron is very hot by design, exceeding 370 C. Do not allow the tip to come into contact with skin, clothing or other objects. When working, you need to use a special holder for a soldering iron.

To summarize, we can say that soldering tin is still widely used in the domestic electronics industry and everyday life. The product is widely represented on the Russian and foreign markets, in the form of lead and lead-free solders. In order to protect the environment and the requirements of international organizations, consumption of the first type will be steadily reduced.

Source: https://rusenergetics.ru/ustroistvo/olovo-dlya-payki

What is tin and what is it used for?

Soft white metal - tin - was one of the first metals that man learned to process. Scientists believe that tin began to be mined much earlier than iron was first discovered.

Some archaeological finds confirm that tin mines in what is now Iraq were in operation four thousand years ago. Tin was traded: merchants exchanged it for gold and precious stones.

In nature, tin is found in the oxide tin ore cassiterite, a mineral whose deposits are found in Southeast Asia, South America, Australia, and China.

From the history

According to historians and archaeologists, tin was first discovered, most likely by accident, in alluvial deposits of cassiterite. Ancient furnaces containing waste slag have been found in the south-west of Great Britain. Among the discovered objects from the era of Ancient Rome and Greece, tin items are very rare, which confirms the assumption that this metal was expensive.

Tin is mentioned in works of Arabic literature of the 8th-9th centuries, as well as in medieval works describing travel and great discoveries. In Bohemia and Saxony, tin began to be mined in the 12th century.

It is interesting that long before people began to mine pure tin, they invented bronze - an alloy of tin and copper. According to some sources, bronze was known to man as early as 2500 BC.

The fact is that tin exists in ores together with copper, so when smelting they obtained not pure copper, but its alloy with tin, that is, bronze. Tin can be found as an incidental impurity in copper utensils of the Egyptian pharaohs made in 2000 BC.

Chemical properties of tin

Tin is inert to water and oxygen at room temperature. The metal also tends to become coated with a thin oxide film when exposed to air.

It was the chemical inertness of tin under normal conditions that made the metal popular among manufacturers of tin containers.

Sulfuric and hydrochloric acid in a diluted state act on tin extremely slowly, and in a concentrated form they dissolve it when heated. When combined with hydrochloric acid, tin chloride is obtained, and when combined with sulfuric acid, tin sulfate is obtained.

When reacting with dilute nitric acid, tin nitrate is obtained, and with concentrated nitric acid, insoluble tin acid is obtained. Tin compounds are of great industrial importance: they are used in the production of electroplating coatings.

Applications of tin

This silvery-white soft metal can be rolled out into a thin foil. Tin does not rust, so it is widely used in various fields. Most often, containers are made from this metal. If tin is applied in a thin layer to another metal, it will give the surface a special shine and smoothness.

This property of tin is used in the manufacture of tin cans. Tin is often used as an anti-corrosion coating. More than a third of all tin mined in the world today is used in the production of food and beverage containers.

Tin cans, familiar to everyone, are made of steel coated with a layer of tin no more than 0.4 microns thick.

Another third of the mined tin is used to make solders - alloys with lead in different proportions. Solders are used in electrical engineering for soldering pipelines.

Such alloys can contain up to 97% tin, copper and antimony, which increase the hardness and strength of the alloy.

Utensils (primarily frage) are made from tin mixed with antimony. In industry, tin is used in various chemical compounds.

Source: http://www.vseznaika.org/chemiks/chto-takoe-olovo-i-dlya-chego-ono-nuzhno/

Tin

 Tin is a ductile, malleable and fusible shiny metal of a silvery-white color. It is used mainly as a safe, non-toxic, corrosion-resistant coating in its pure form or in alloys with other metals.

The main industrial uses of tin are in tinplate (tinned iron) for making containers, in solders for electronics, in household piping, in bearing alloys, and in coatings of tin and its alloys.

The element consists of 10 isotopes with mass numbers 112, 114-120, 122, 124; the latter is weakly radioactive; The 120Sn isotope is the most common (about 33%).
 

STRUCTURE

Tin has two allotropic modifications: a-Sn (gray tin) with a face-centered cubic crystal lattice and b-Sn (regular white tin) with a body-centered tetragonal crystal lattice.

The phase transition b -> a is accelerated at low temperatures (-30 ° C) and in the presence of nuclei of gray tin crystals; There are known cases when tin products in the cold crumbled into gray powder (“tin plague”), but this transformation, even at very low temperatures, is sharply inhibited by the presence of minute impurities and therefore rarely occurs, representing more scientific than practical interest.

PROPERTIES

The density of b-Sn is 7.29 g/cm3, the density of a-Sn is 5.85 g/cm3.
Melting point 231.9°C, boiling point 2270°C. Temperature coefficient of linear expansion 23·10-6 (0-100 °C); specific heat capacity (0°C) 0.225 kJ/(kg K), that is, 0.0536 cal/(g °C); thermal conductivity (0°C) 65.8 W/(m K), that is, 0.157 cal/(cm sec °C); specific electrical resistance (20 °C) 0.115·10-6 ohm·m, that is, 11.5·10-6 ohm·cm. Gray tin is diamagnetic, and white tin is paramagnetic.

Tensile strength 16.6 MN/m2 (1.7 kgf/mm2); relative elongation 80-90%; Brinell hardness 38.3-41.2 Mn/m2 (3.9-4.2 kgf/mm2). When bending tin rods, a characteristic crunch is heard from the mutual friction of the crystallites.

Pure tin has low mechanical strength at room temperature (you can bend a tin rod and hear a characteristic cracking sound caused by the friction of individual crystals against each other) and is therefore rarely used.

Reserves and production

Tin is a rare trace element; tin ranks 47th in terms of abundance in the earth's crust. The Clark content of tin in the earth's crust ranges, according to various sources, from 2·10−4 to 8·10−3% by mass.

The main mineral of tin is cassiterite (tin stone) SnO2, containing up to 78.8% tin. Much less common in nature is stannin (tin pyrite) - Cu2FeSnS4 (27.5% Sn). The world's tin deposits are located mainly in China and Southeast Asia - Indonesia, Malaysia and Thailand.

There are also large deposits in South America (Bolivia, Peru, Brazil) and Australia.

In Russia, tin ore reserves are located in the Chukotka Autonomous Okrug (Pyrkakai stockworks; Valkumey mine/village, Iultin - mining was closed in the early 1990s), in the Primorsky Territory (Kavalerovsky district), in the Khabarovsk Territory (Solnechny district, Verkhnebureinsky district ( Pravourmiyskoye deposit)), in Yakutia (Deputatskoye deposit) and other areas.

During the production process, the ore-bearing rock (cassiterite) is crushed to particle sizes of an average of ~ 10 mm in industrial mills, after which cassiterite, due to its relatively high density and mass, is separated from the waste rock by vibration-gravity method on dressing tables. In addition, the flotation method of ore enrichment/purification is used. In this way, it is possible to increase the tin content in the ore to 40-70%.

Next, the concentrate is roasted in oxygen to remove impurities of sulfur and arsenic. The resulting tin ore concentrate is smelted in furnaces. During the smelting process, it is restored to a free state through the use of charcoal in the reduction, the layers of which are laid alternately with layers of ore, or aluminum (zinc) in electric furnaces: SnO2 + C = Sn + CO2.

Particularly pure tin of semiconductor purity is prepared by electrochemical refining or the zone melting method.

ORIGIN

The main form of occurrence of tin in rocks and minerals is scattered (or endocript). However, tin also forms mineral forms, and in this form it is often found not only as an accessory in acidic igneous rocks, but also forms industrial concentrations mainly in oxide (cassiterite SnO2) and sulfide (stannine) forms.

In general, the following forms of tin occurrence in nature can be distinguished:

1. Diffuse Form: The specific form of occurrence of tin in this form is unknown. Here we can talk about an isomorphically dispersed form of tin occurrence due to the presence of isomorphism with a number of elements (Ta, Nb, W - with the formation of typically oxygen compounds; V, Cr, Ti, Mn, Sc - with the formation of oxygen and sulfide compounds). If tin concentrations do not exceed certain critical values, then it can isomorphically replace the named elements. The mechanisms of isomorphism are different.
2. Mineral Form: Tin is found in concentrator minerals. As a rule, these are minerals in which iron Fe+2 is present: biotites, garnets, pyroxenes, magnetites, tourmalines, etc. This relationship is due to isomorphism, for example, according to the scheme Sn+4 + Fe+2 → 2Fe+3. In tin-bearing skarns, high concentrations of tin are found in garnets (up to 5.8 wt.%) (especially in andradites), epidotes (up to 2.84 wt.%), etc.

Source: http://mineralpro.ru/minerals/tin/

Characteristics and properties of tin, its advantages and disadvantages as a building material

Tin is one of the seven oldest metals, that is, known to human civilization. Tin is a component of bronze, an alloy that was so important in the past that the corresponding time period is called the “Bronze Age.”

Nowadays, tin has lost so much importance, but continues to be used. Therefore, today we will consider the concept, features, formula of tin, its technical significance and areas of application, the price for 1 kg of scrap metal and similar nuances.

There is often debate about whether tin is a metal or a non-metal. The chemical element tin - Sn, is placed in the 14th group of D.I. Mendeleev’s table of elements in the 5th period along with carbon, silicon and germanium. This arrangement indicates that the substance is amphoteric: it exhibits both acidic and basic properties.

Molecular weight is 50, that is, the substance belongs to the light category.

This video will tell you about tin as a unique element:

Tin is a light, malleable, ductile white metal with a soft silvery sheen. Over time, the shine on products fades, which, as a rule, is not considered a drawback. The metal is a rare trace element, which makes its extraction difficult.

The use of tin is directly related to its properties:

• tin melting point – +231.9 C;
• boiling point – 2600 C;
• casting temperature is 260–300 C, which determines the excellent malleability of both the metal itself and its alloys;
• thermal conductivity at normal temperature – 65.8 W/(m•K);
• specific electrical conductivity – 8.69 MS/m;
• tensile strength – up to 20 MPa.

All properties of metals are assessed at normal temperature, that is, at 20 C. Accordingly, the data are applicable for that modification of the substance that is stable at this temperature.

Tin is completely non-toxic, does not affect the human body, and therefore is used in the food industry. Using pewter or water pipes won't cause any harm either.

In the human body, the element is found mainly in the bones, where it contributes to the process of normal bone tissue renewal. Tin is a macronutrient: for normal functioning a person needs from 2 to 10 mg per day. In fact, the metal enters the body with food in much larger quantities, but since the intestines are able to absorb no more than 3–5% of the intake, poisoning is impossible.

A lack of macronutrients primarily slows down growth, and also causes hearing loss, baldness, and changes in the composition of bone tissue. But the absorption of tin vapor or dust containing its compounds can lead to poisoning.

Metal properties

Tin is a fragile metal. Of much greater interest to the modern national economy is its high corrosion resistance. Tin coating has long been used to protect metal objects, particularly cans.

Another interesting property is the ability to connect different metals, forming a strong bond that is resistant to external influences. For this purpose, both tin itself is used - in particular, for tinning dishes and household items, and solders - alloys of metal with lead. The alloy is classified as a soft solder and is actively used in electrical and radio engineering.

In terms of its qualities and appearance, the substance is closest to aluminum. In fact, the similarity is very relative. Both metals are lightweight, and both are insensitive to corrosion and weather factors. However, aluminum is unstable to the action of acids and alkalis, even weak ones - acetic acid, for example, while tin reacts only with concentrated strong acids.

Next, we will talk about the interesting advantages and disadvantages of tin, its physical and chemical properties, the production and use of the material.

Advantages and disadvantages

In construction, metal is used very limitedly, since it does not have mechanical strength, resistance to tearing, and so on. Alloys are much more often used.

Advantages:

• malleability – important in the manufacture of household items. Dishes, lamps, stands, and decorative items can look incredibly beautiful. At the same time, the forging temperature is low, and, therefore, the price of the product increases slightly;
• inertness makes the metal applicable in the food industry, since it does not interact in any way with organic acids or bases;
• low melting point facilitates the process of applying metal to the surface and reduces energy losses;
• tin and its alloy with lead is the most famous, widespread and affordable soft solder ;
• the metal and its alloys are anti-friction . If rotating and contacting parts cannot be made from the substance itself, then tin coating of such a part of the machine significantly reduces friction and, therefore, protects against premature wear.

Flaws:

• The conditional disadvantages of metal include its fragility. Tin is completely unsuitable for the production of any parts and components that require resistance to stress;
• This is a rare element, its extraction and smelting are quite expensive, so the substance itself turns out to be expensive.

It is quite difficult to say exactly how much 1 kg of tin costs, since the cost of metals is constantly changing.

A specialist will tell you what to do if the tin does not stick in the video below:

Metals are homogeneous in structure, but different structures can exist at different temperatures. Moreover, the phases differ markedly from each other in properties.

• The best known is the β-modification of the metal, since it is this modification that is present at a temperature of 20 C. It becomes stable at 13.2 C, and it is its properties - thermal conductivity, boiling point - that are given as properties of the metal.
• However, at temperatures below 13.2 C, the substance transforms into the α-modification, the so-called gray tin. The α-modification has a different crystal lattice, the substance has a lower density, is not plastic and is not malleable.

The transition from the β-modification to the α- is accompanied by a change in volume due to the difference in density, and this leads to the destruction of the tin product. The phenomenon is known as the "tin plague". This feature greatly limits the scope of application of the metal.

• In the temperature range from 161 to 232 C there is a γ phase. However, its properties are of interest only to specialists.

In nature, tin occurs in rocks as a trace element, but can also have mineral forms. The most famous of the latter is cassiterite, a metal oxide, as well as stanine, tin pyrite - its compound with sulfur. Other minerals are also being developed.

Production of material

A profitable business is the development of ore with a tin content of 0.1%. In fact, deposits are exploited where the ore is even poorer - up to 0.01%. Mineral extraction is carried out using different methods depending on the nature of the deposit - alluvial or primary.

The basis of the placer deposit is sand. The essence of mining comes down to washing the sand and concentrating the ore mineral. Development of the main one is more complicated, since it involves the construction and operation of mines.

• The tin mineral concentrate is transported to a non-ferrous metal smelting plant. Here the concentrate is enriched again, then crushed and washed.
• The ore concentrate obtained in this way is reduced in special furnaces. The process is repeated at least 2 times, since the slag after complete recovery contains too much substance.
• At the last stage, rough tin is refined - purified from impurities using a thermal or electrolytic method.

The resulting material is used for its intended purpose.

The main property that determines the area of ​​use of the metal is its corrosion resistance. Moreover, tin is not only itself insensitive to chemically aggressive substances, but also imparts this feature to most alloys.

• More than 50% of all metal produced in the world is used to produce tin plate, that is, a sheet, or more often, an object made of steel, coated with a thin layer of tin. This technology was first used to protect cans and is still used today.
• Tin can be rolled out, so thin-walled pipes are made from it. Their domestic use, however, is very limited, since such products do not tolerate low temperatures.
• But plumbing fixtures, fittings and other accessories are very popular and known to everyone. The material is hygienic, has lower thermal conductivity than steel, for example, therefore it is actively used in the manufacture of bathtubs and washbasins.
• Tin is used to make dishes, small household and decorative items, and jewelry. The reason for this is the excellent malleability and beautiful soft color of tin metal.
• A very large proportion of the substance is used to produce alloys. The first place is, of course, occupied by the production of bronze. The latter ideally combines strength and corrosion resistance, which makes it a very popular decorative and construction material.
• Solders are no less famous and popular. Moreover, in this case, tin can be used independently - for dishes, for example, and as part of an alloy.
• Tin is a tonally resonant metal. Both bronze and an alloy of metal with lead were and are used in the manufacture of musical instruments. Bronze bells have been known since very ancient times. Organ pipes are made from an alloy with lead. Moreover, it is its quantity in the alloy that determines the tone of the product.

Tin is a light and fragile metal, but it has excellent corrosion resistance and malleability. It is these properties that determine the use of tin.

This video will tell you how to melt tin at home:

Source: http://stroyres.net/metallicheskie/vidyi/tsvetnyie/olovo/harakteristiki-preimushhestva-i-nedostatki.html

Everything you need to know about liquid tin, making your own solution

Tin is one of the chemical elements that has found application in various industrial areas and everyday life. It is a light metal, ductile, malleable and fusible. It has a silvery-white tint and shine. One form of the substance is liquid. Mainly used in radio construction. Liquid tin is ideal for chemical tinning of copper parts, in particular printed circuit boards. This treatment method significantly increases their service life and prevents the formation of corrosion.

Details about liquid tin

Liquid tin is a solution that is used to coat printed circuit boards. Thus, the part becomes protected from negative influences. In addition, the surface prepared using this method is completely ready for soldering, because The solder adheres to it much better.

The advantages of liquid tin are obvious:

• with its help you can tin a large board, with a complex circuit or with particularly thin traces and distances. It is sometimes very difficult to do this with a regular soldering iron, and sometimes completely impossible;
• the surface treated with liquid will not melt under the influence of high temperatures, because the melting temperature of tin is 220 degrees;
• The tinning process is safe and quite simple, so even a person who is far from working with chemicals can handle it.

What does liquid tin look like?

Liquid tin can be purchased at any specialized store or made yourself, especially since all components are completely accessible.

Composition and methods of using liquid tin

The chemical is sold in plastic bottles of various sizes. The composition of liquid tin includes: a reducing agent, a stabilizer, deionized water and tin salt.

Tinning is best done immediately before soldering the board. Before the procedure, the part is prepared. It is cleaned and degreased with alcohol. It is not recommended to sand the board, but if necessary, you can sand it with GOI paste and then clean it.

Next, the tinning itself is carried out directly. Tin in a liquid state is shaken well, poured into a prepared plastic container and heated to room temperature in a water bath. The board is immersed in the solution for 20-30 minutes. The result is a layer of 1 μm. If a thicker layer is needed, the tinning procedure is repeated. After this, the product is washed with running water and wiped dry with a clean cloth. Before use, the finished board is stored in a stationery file or plastic bag.

Liquid tin is sold in plastic bottles of various sizes

The amount of liquid tin is calculated from the proportion of 1 liter per ½ sq. m. surface. The liquid tin solution can be reused as many times as necessary, until it is exhausted. However, those who have already tested the substance in practice note a decrease in its performance within a couple of months after opening the bottle.

Making liquid tin with your own hands

When making liquid tin at home, you can use both hydrochloric and sulfuric acid. The second is more dangerous, but makes it possible to carry out the tinning procedure at room temperature, because The solution then does not crystallize. Consider a safe recipe using hydrochloric acid.

To prepare a chemical tinning solution, you will need the following components:

• tin chloride or “tin salt” (SnCl2*2H2O) - 14 g;
• hydrochloric acid - 55 ml;
• thiourea - 55 g;
• sodium hypophosphite - 35 g;
• potassium iodide - 15 ml;
• bismuth-iodine complex - 0.6 g;
• any dishwashing detergent - 3-6 ml;
• distilled water - approximately 1-1.5 liters.

The tools and utensils you will need are kitchen scales, a measuring cup, a syringe and a plastic spoon.

The step-by-step process of creating “homemade” liquid tin looks like this.

1. In a measuring cup, mix hydrochloric acid, tin chloride and 150 ml of distilled water.
2. Thiourea is poured into the resulting mixture, resulting in a white mushy mass.
3. Add the full amount of sodium hypophosphite there and mix well.
4. Next you need to prepare the components for the bismuth-iodine complex. To do this, in a separate container, 6 g of potassium hydroxide is combined with 30 ml of pharmaceutical iodine. Bismuth nitrate is prepared from 0.6 g of Rose alloy, which is dissolved in 7 ml of nitric acid. The liquid that appears on the surface is collected with a syringe, and the sediment is disposed of. The two resulting substances are mixed and a bismuth-iodine complex is obtained in the precipitate, and potassium iodide in the solution.
5. Potassium iodide and approximately the size of a match head of sediment from it is added to the main thiourea composition. Mix everything well.
6. Add detergent to the resulting mass and mix.
7. Distilled water is heated to 90 degrees and added to the solution, bringing the volume to 1 liter, mix well until all components are dissolved.

To create liquid tin you need hydrochloric acid

If the process of preparing liquid tin was carried out correctly, the result should be a transparent liquid with a yellowish tint. Now you can test the resulting tinning solution. To do this, any board is degreased and immersed in liquid tin for a minute. The copper surface should be coated with a thin layer of a chemical composition. It is necessary to ensure that the temperature of the solution is not below 50 degrees, otherwise it may begin to crystallize.

Source: https://1nerudnyi.ru/zhidkoe-olovo-01/

How to make tin at home? Step by step casting process

Today, tin is a common metal. However, in the 16th and 17th centuries, it was quite rare and valuable, so Russia bought it from other countries. Tin was used to coat iron products to protect them from rust.

From this metal, Russian craftsmen created dishes with relief patterns, since soft, pliable tin could easily be processed with a chisel. After casting the product, the master decorated it with intricate patterns or an engraved inscription.

Today, the Moscow Historical Museum has various examples of tin utensils that have been preserved from ancient times.

Briefly about malleable tin

Metal tin has such a crystal structure that when it is bent, the metal crystals crunch as a result of friction against each other. This crunch is a distinctive feature of pure tin from its alloys, which do not emit sounds when bent.

It is possible to apply various decorative coatings based on tin or any alloy made from it at home. At the same time, the question may arise, how to make tin yourself? It is extracted using electrochemical etching methods using an electrolyte solution, which you will need to make yourself, using pure tin and its salts.

Craftsmen can obtain tin at home in the following ways:

• Use chemical reactions to produce tin oxide and then melt it in a crucible. As a result, pure tin will be released.
• Obtain tin chloride, and then use electrolysis cans from cans with an electrolyte based on the existing chloride to isolate the tin.

How to get tin chloride at home?

A simpler and cheaper method for producing tin chloride is to use tin-lead solder.

1. You need to take concentrated hydrochloric acid, bring it to a boil and dissolve solder in it.
2. The next step is to strongly cool the solution, during which lead chloride will precipitate in it.
3. The resulting precipitate is filtered with decantation, and an electrolyte (which is practically pure tin chloride with a small amount of impurities) is prepared on the basis of the filtered solution.
4. Due to the rapid oxidation of stannous chloride, the resulting solution must be used immediately.

how to make tin chloride at home

How to get pure tin at home?

In order to make an electrolyte, you need to take a small portion of tin chloride as a seed. Later, after isolation, it will be possible to prepare a purer chloride solution. To do this, you need to take aqua regia or hydrochloric acid and dissolve the metal.

Pour an alkaline solution (9-10%) into a 7% solution of SnCl2 (chloridol), stirring constantly, as a result of which the formation and precipitation of a white precipitate - tin hydroxide - will be observed.

It is necessary to stir the solution until it becomes completely transparent, which will indicate the readiness of the electrolyte.

How to make tin at home? To do this, you will need a fairly large tin can (3-5 liters) and a lid made of dielectric material.

The cans have a tinned inner surface - that is, a layer of tin that protects the iron can itself from oxidation, and the food product contained in it from spoilage. Therefore, it is possible to extract tin from cans for reuse.

You need to remove the sticker from the jar and remove dirt from it, for which you need to boil it in a strong soda solution for 30 minutes. The following is done:

1. A carbon cathode is placed in the center of the jar.
2. Connect the anode to the can body.
3. Fill the electrolyte and connect the power supply (4V). To do this, you can take several batteries or a battery connected in series.
4. To increase the amount of tin produced, cut some old cans into pieces and pour them into the electrolyzer, but you must prevent them from coming into contact with the cathode. One medium-sized tin contains 0.5 g of tin.
5. The result of the experiment is the release of spongy tin at the cathode. It must be collected and melted in a crucible into a metal of a characteristic silver color. Why can tin be melted at home? Because it has a melting point of 239˚C, and iron, for comparison, has a melting point of 1538.85˚C.

about tin casting at home

Tin casting at home

Today, making small figurines and products from tin at home is not only interesting, but also quite profitable. After all, many collectors are willing to pay a lot of money for a tin soldier, a model of military equipment, or just a souvenir. Amateur artists who want to learn how to cast parts usually use tin for this, since it has the following positive qualities:

• Attractive beautiful color similar to silver.
• Tin is technologically advanced and has a low melting point.
• Plastic, easy to engrave and mint, “molded” with a soldering iron.

A skilled craftsman, using simple equipment, is able to transform a small silver ingot into a beautiful sculpture, lantern, candlestick, casket, medal, brooch, bracelet, cufflink and much more. In addition, openwork and relief plates are created from tin to decorate boxes, door hinges, handles, and keyholes. How is tin casting done at home? This process consists of the following stages and features:

1. The production of future products begins with the creation of color sketches on a sheet of paper.
2. Afterwards, polymer clay is taken and a figurine is prepared from it to create a shape. In this case, every smallest detail is applied with a stack and a thin awl.
3. Making the mold is the most critical stage. It must have the perfect connector. This is necessary for easy and safe removal of the casting. As a rule, casting molds are made collapsible, consisting of 2 parts.
4. The most optimal material for the mold is plaster or silicone, but in order to make a silicone mold, you need to spend much more material and time.
5. In addition, stores sell special sealants that are poured onto models, they harden and thus become reusable molds for pouring.

1. In cases where the future product will contain many small parts, the mold is made with an insert.
2. An important role is played by the size of the channel in the mold through which the metal is poured into it. The smaller it is, the slower the mold is filled, and there is a danger of the metal cooling quickly, which can lead to the formation of cavities.
3. When casting a part, the two halves of the mold should be folded together and placed between a plywood sheet about 12 millimeters thick. Then you need to tighten them with a tight elastic band.
4. After preparing the mold, the metal is heated. The readiness of the alloy for pouring is determined by the formation of a yellowish film. If the metal is overheated, the film will acquire a blue or purple tint.
5. Pouring metal into the mold must be done in a thin stream, while tapping the mold a little, thus preventing air retention in it. It is necessary to remember the rules for safe work with heated alloys.
6. After the mold is filled with metal, it must be left for some time to cool and harden the alloy inside it.
7. Then the mold is opened, and the finished product is carefully removed from it using tongs. As a rule, there are always defects on the first product. Therefore, the figurine is further processed - the flash (metal that has flowed into the seams between the two parts of the form) is removed. They are cleaned using tools such as a scalpel or scraper.
8. Next, the seams are sanded with fairly fine sandpaper. When making complex figures and products that are cast in separate parts, these parts are connected with a soldering iron.

1. Epoxy glue is used to glue small parts. The places where the parts were soldered and glued are carefully and carefully sanded.
2. Then you should prepare a strong solution of soda and wash the finished figurine with a thin brush to remove the flux.
3. If necessary, the finished product is painted with acrylic paints.

Having successfully mastered this fascinating ancient craft, a skilled craftsman will have the opportunity not only to do what he loves, but also to earn good money. Plus, it would make a great 10th wedding anniversary (tin anniversary) gift.

Have you ever thought about how to get tin at home? Did you succeed? Tell us about it in the comments.

Source: https://www.rutvet.ru/in-kak-sdelat-olovo-v-domashnih-usloviyah-poshagovyy-process-litya-8136.html

Tin: properties, interesting facts, applications

Tin is a light non-ferrous metal, a simple inorganic substance. In the periodic table it is designated Sn, stannum. Translated from Latin it means “durable, resistant.” Initially, this word was used to refer to an alloy of lead and silver, and only much later did they begin to call pure tin this way. The word "tin" has Slavic roots and means "white".

Metal is a trace element, and not the most common on earth. It occurs in nature in the form of various minerals. The most important for industrial mining: cassiterite - tin stone, and stannin - tin pyrite. Tin is extracted from ores, usually containing no more than 0.1 percent of this substance.

Properties of tin

Lightweight, soft, ductile metal with a silvery-white color. It has three structural modifications, passes from the α-tin (gray tin) state to β-tin (white tin) at a temperature of +13.2 °C, and to the γ-tin state at +161 °C. The modifications differ greatly in their properties. α-tin is a gray powder that is classified as a semiconductor, β-tin (“ordinary tin” at room temperature) is a silvery, malleable metal, and γ-tin is a white, brittle metal.

In chemical reactions, tin exhibits polymorphism, that is, acidic and basic properties. The reagent is quite inert in air and water, as it quickly becomes covered with a durable oxide film that protects it from corrosion.

Tin easily reacts with non-metals, but with difficulty with concentrated sulfuric and hydrochloric acid; does not interact with these acids in a diluted state. It reacts with concentrated and dilute nitric acid, but in different ways. In one case, tin acid is obtained, in the other, tin nitrate. It reacts with alkalis only when heated. With oxygen it forms two oxides, with oxidation states 2 and 4. It is the basis of a whole class of organotin compounds.

Impact on the human body

Tin is considered safe for humans, it is present in our body and every day we get it in minimal quantities from food. Its role in the functioning of the body has not yet been studied.

Tin vapor and its aerosol particles are dangerous, since with prolonged and regular inhalation it can cause lung diseases; Organic tin compounds are also poisonous, so you need to wear protective equipment when working with it and its compounds.

A tin compound such as tin hydrogen, SnH4, can cause severe poisoning when eating very old canned food in which organic acids have reacted with a layer of tin on the walls of the can (the tin from which cans are made is a thin sheet of iron coated tin on both sides). Tin hydrogen poisoning can even be fatal. Symptoms include seizures and a feeling of loss of balance.

When the air temperature drops below 0 °C, white tin transforms into a modification of gray tin. In this case, the volume of the substance increases by almost a quarter, the tin product cracks and turns into gray powder. This phenomenon came to be called the “tin plague.”

Some historians believe that the “tin plague” was one of the reasons for the defeat of Napoleon’s army in Russia, as it turned the buttons on the clothes of French soldiers and belt buckles into powder, and thereby had a demoralizing effect on the army.

But here is a real historical fact: the expedition of the English polar explorer Robert Scott to the South Pole ended tragically, partly because all their fuel spilled out of the tanks sealed with tin, they lost their snowmobiles, and they did not have enough strength to walk.

Application

— Most of the smelted tin is used in metallurgy to produce various alloys. These alloys are used for the production of bearings, foil for packaging, tinplate, bronze, solders, wires, and typefaces. Tin in the form of foil (staniol) is in demand in the production of capacitors, tableware, works of art, and organ pipes.

— Used for alloying structural titanium alloys; for applying anti-corrosion coatings to products made of iron and other metals (tinning).— The alloy with zirconium has high refractoriness and resistance to corrosion.— Tin (II) oxide is used as an abrasive in the processing of optical glasses.— Included in the materials used for the manufacture of batteries.— In the production of “gold” paints and dyes for wool.

— Artificial radioisotopes of tin are used as a source of γ-radiation in spectroscopic research methods in biology, chemistry, and materials science.

— Tin dichloride (tin salt) is used in analytical chemistry, in the textile industry for dyeing, in the chemical industry for organic synthesis and production of polymers, in oil refining for decolorizing oils, in the glass industry for glass processing.

— Tin boron fluoride is used for the production of tin, bronze, and other alloys needed by industry; for tinning; lamination.

Source: https://pcgroup.ru/blog/olovo-svojstva-interesnye-fakty-primenenie/

Chemical element tin. Properties and uses of tin

Each chemical element of the periodic table and the simple and complex substances formed by it are unique. They have unique properties, and many make an undeniably significant contribution to human life and existence in general. The chemical element tin is no exception.

People's acquaintance with this metal goes back to ancient times. This chemical element played a decisive role in the development of human civilization; to this day, the properties of tin are widely used.

Tin in history

The first mentions of this metal, which, as people previously believed, even had some magical properties, can be found in biblical texts. Tin played a decisive role in improving life during the Bronze Age.

At that time, the most durable metal alloy that man possessed was bronze, which can be obtained by adding the chemical element tin to copper.

For several centuries, everything from tools to jewelry was made from this material.

After the discovery of the properties of iron, the tin alloy did not cease to be used; of course, it is not used on the same scale, but bronze, as well as many of its alloys, are actively used by man today in industry, technology and medicine, along with salts of this metal, for example, such as chloride tin, which is obtained by reacting tin with chlorine, this liquid boils at 112 degrees Celsius, dissolves well in water, forms crystalline hydrates and smokes in air.

The chemical element tin (the Latin name stannum - “stannum”, written with the symbol Sn) was rightfully placed by Dmitry Ivanovich Mendeleev at number fifty, in the fifth period. It has a number of isotopes, the most common isotope 120.

This metal is also in the main subgroup of group six, along with carbon, silicon, germanium and flerovium.

Its location predicts amphoteric properties; tin is equally characterized by both acidic and basic characteristics, which will be described in more detail below.

The periodic table also shows the atomic mass of tin, which is 118.69. The electronic configuration is 5s25p2, which in the composition of complex substances allows the metal to exhibit oxidation states +2 and +4, giving away two electrons only from the p-sublevel or four from the s- and p-, completely emptying the entire outer level.

Electronic characteristics of the element

According to the atomic number, the perinuclear space of a tin atom contains as many as fifty electrons; they are located on five levels, which, in turn, are split into a number of sublevels. The first two have only s- and p-sublevels, and starting from the third there is a threefold splitting into s-, p-, d-.

Let us consider the outer electronic level, since it is its structure and filling with electrons that determine the chemical activity of the atom.

In an unexcited state, the element exhibits a valence of two; upon excitation, one electron transitions from the s-sublevel to a vacant position in the p-sublevel (it can contain a maximum of three unpaired electrons).

In this case, tin exhibits a valence and oxidation state of 4, since there are no paired electrons, which means that during the chemical interaction nothing holds them at the sublevels.

Simple substance metal and its properties

The simple substance tin is a silver-colored metal that belongs to the group of fusible metals. The metal is soft and relatively easy to deform. A number of features are inherent in such a metal as tin.

Temperatures below 13.2 degrees Celsius are the boundary of the transition of the metal modification of tin into powder form, which is accompanied by a change in color from silver-white to gray and a decrease in the density of the substance. Tin melts at 231.9 degrees and boils at 2270 degrees Celsius.

The crystalline tetragonal structure of white tin explains the characteristic crunching of the metal when it is bent and heated at the bend by friction of the crystals of the substance against each other. Gray tin has a cubic system.

The chemical properties of tin are dual; it enters into both acidic and basic reactions, exhibiting amphotericity. The metal reacts with alkalis, as well as acids such as sulfuric and nitric, and is active when reacting with halogens.

Tin alloys

Why are alloys with a certain percentage of constituent components used more often instead of pure metals? The fact is that the alloy has properties that the individual metal does not have, or these properties are much stronger (for example, electrical conductivity, corrosion resistance, passivation or activation of the physical and chemical characteristics of metals if necessary, etc.). Tin (the photo shows a sample of pure metal) is part of many alloys. It can be used as a supplement or base substance.

Today, a large number of alloys of such a metal as tin are known (their price varies widely), let’s consider the most popular and used (the use of certain alloys will be discussed in the corresponding section). In general, stannum alloys have the following characteristics: high ductility, low melting point, low hardness and strength.

Some examples of alloys

• An alloy of tin and lead with some alloying additives (antimony, copper, cadmium, zinc, silver, indium) is the so-called soldering tin, the percentage of stannum in it to achieve the best fastening properties should be 49-51 or 59-61 percent. The strength of the connection is ensured by the formation of a solid solution by tin with the metal surfaces being bonded.
• Garth, an alloy of tin, lead and antimony, is the basis of printing ink (which is why it is not recommended to wrap food in newspapers to avoid introducing unwanted concentrations of these metals).
• Babbitt - an alloy of tin, lead, copper and antimony - is characterized by a low coefficient of friction and high wear resistance.
• Indium-tin alloy is a low-melting material characterized by refractoriness, corrosion resistance and significant strength.

The most important natural compounds

Tin forms a number of natural compounds - ores. The metal forms 24 mineral compounds, the most important for industry being tin oxide - cassiterite, as well as stanine - Cu2FeSnS4. Tin is scattered in the earth's crust, and the compounds formed by it are of magnetic origin. Salts of polytin acids and tin silicates are also used in industry.

The chemical element tin is a trace element in its quantitative content in the human body. Its main accumulation is in bone tissue, where the normal metal content contributes to its timely development and the general functioning of the musculoskeletal system. In addition to bones, tin is concentrated in the gastrointestinal tract, lungs, kidneys and heart.

It is important to note that excessive accumulation of this metal can lead to general poisoning of the body, and longer exposure can even lead to unfavorable gene mutations. Recently, this problem has become quite relevant, since the ecological state of the environment leaves much to be desired.

There is a high probability of tin intoxication among residents of megacities and areas nearby industrial zones. Most often, poisoning occurs through the accumulation of tin salts in the lungs, for example, tin chloride and others.

At the same time, a lack of microelement can cause growth retardation, hearing loss and hair loss.