Many modern technological devices and aids have been created due to the unique properties of substances found in nature.Mankind by experimentation and careful study of the elements around us is constantly modernizing own invention - this process is called technological progress.It is based on simple, accessible to everyone the things that surround us in everyday life.For example, the sand, what it can be surprising and unusual?Scientists were able to isolate from a silicon - a chemical element, without which there would be no computer equipment.The area of application is diverse and is constantly expanding.This is achieved through the unique properties of the silicon atom in its structure and connectivity with other simple substances.
Feature
in the periodic system, developed by Mendeleev, silicon (chemical element) is represented by Si.It refers to the non-metals, is located in the main the fourth group of the third period, has the atomic number 14. Its proximity to carbon is not accidental: their properties are largely comparable.Not found in nature in pure form, as an active component and has a sufficiently strong bond with oxygen.Base material - silica, which is an oxide, and silicates (sand).When this silicon (its natural compound) is one of the most common chemical elements in the world.According to the mass fraction of the content it is second only to oxygen (over 28%).The top crust layer comprises silicon dioxide in the form (this quartz), various types of clay and sand.The second most common group is made up of its silicates.At a depth of about 35 km from the surface layers are arranged granite and basalt deposits, which include silicon compounds.The percentage content of the Earth's core has not yet figured out, but coming to the surface layers of the mantle (900 km) include silicates.In the composition of seawater silicon concentration is 3 mg / l, lunar soil consists of 40% of its compounds.The vast expanses of space that mankind has so far examined, contain this chemical element in large quantities.For example, spectral analysis of meteorites, which approaches the ground at a distance that is available to researchers, has shown that they consist of 20% of silicon.There is a possibility of formation of life on the basis of this element in our galaxy.
research process
history of the discovery of the chemical element silicon has several stages.Many substances, systematized Mendeleev have been used by mankind for centuries.The elements in a natural form, i .e.compounds which were not subjected to chemical treatment, and all of their properties have not been known to people.In the process of studying all the features of the substance had appeared new areas of use.The properties of silicon to date have not been studied until the end - this element is sufficiently wide and varied range of application leaves room for new discoveries for future generations of scientists.Modern technology will significantly accelerate this process.In the XIX century, many famous chemists have been trying to obtain silicon in a pure form.For the first time it was done Tenaru L. and J. Gay-Lussac in 1811, but the discovery of the element belongs to J. Berzelius, who was able not only to identify the substance, but to describe it.A chemist from Sweden got silicon in 1823, for this he used a metal potassium and potassium salt.The reaction took place at the catalyst in the form of heat.The resulting substance is a simple gray-brown color is an amorphous silicon.Crystal pure element was obtained in 1855, Sainte-Claire Deville.The complexity of the allocation directly related to the high strength of atomic bonds.In both cases, the chemical reaction is directed to a process of purification from impurities, wherein the amorphous and crystalline models have different properties.
Silicon: chemical element pronunciation
first name of the resulting powder - Kizel - was suggested by Berzelius.In the United Kingdom and the United States silicon and today was referred to as silicon (Silicium) or silicone (Silicon).The term comes from the Latin "flint" (or "stone"), and in most cases it is tied to the concept of "land" due to the wide spread in nature.Russian pronunciation of the chemical can be different, it all depends on the source.He was called silica (Zakharov applied the term in 1810), Sicily (1824, Dvigubsky, Solovyov), silica (1825, fear), and only in 1834, the Russian chemist Germain Henri Hess enters the name, which until now usedin most sources - silicon.In the periodic table it is represented by Si.How to read a chemical element silicon?Many scientists English-speaking countries utter his name as "B" or use the word "silicon".Hence the world-famous name of the valley, which is a research and production area of computer technology.The Russian-speaking people call the element silicon (from the Greek word "cliff Mountain").
Being in nature: field
Entire mountain ranges are composed of silicon compounds, which in its pure form does not appear, because all the known minerals are silica and silicates (aluminosilicates).Amazing beauty of the stones used by people as an ornamental material - is opal, amethyst, quartz, different types, jasper, chalcedony, agate, rock crystal, carnelian and many others.They were formed due to the occurrence of the silicon of various substances, which have defined the density, texture, color and direction of use.All the inorganic world may be associated with these chemicals that in the natural environment forms strong bonds with metals and metals (zinc, magnesium, calcium, manganese, titanium, and so on. D.).By comparison with other substances, silicon fairly easily accessible for extraction at industrial scale: it is found in most types of ores and minerals.Therefore, actively mined deposits are tied more to the available energy sources than to the territorial clusters of matter.Quartzite and quartz sand are available in all countries.The largest manufacturers and suppliers of silicon are: China, France, Norway, United States (West Virginia, Ohio, Alabama, New York), Australia, South Africa, Canada, Brazil.All manufacturers use different methods, which depend on the type of product (white, a semiconductor, high-silicon).Chemical element enriched additionally or alternatively, purified from all types of impurities has unique properties which depend on their subsequent use.This also applies to a substance.The structure of the silicon determines its scope.
history
use very often because of the similarity of names of people confuse silicon and flint, but these concepts are not identical.To be clear.As already mentioned, the nature of silicon in pure form does not occur, which is not the compounds (the same silica).The main minerals and rocks formed dioxide substance under consideration - a sand (water and silica), quartz and quartzite, feldspar and flint.The latter heard must be all, because it is given great importance in the history of mankind.With this link the first stone tools, created by people in the Stone Age.Its sharp edges formed during calving from the main breed, greatly facilitates the work of ancient housewives and the possibility of sharpening - hunters and fishermen.Flint did not have the strength of metal products, but the failed instruments could easily be replaced.Its use as a flint lasted many centuries - until the invention of alternative sources.
With regard to contemporary realities, the properties of silicon make it possible to exploit the material for decoration or to create ceramic ware, with, in addition to a beautiful aesthetic appearance, it has a number of excellent functional qualities.A separate area of its application due to the invention of glass about 3000 years ago.This event provided an opportunity to create a mirror, dishes, stained glass mosaic of compounds containing silicon.Formula supplemented initial substances necessary components that allow you to attach the product the desired color and effect on the strength of the glass.Amazing beauty and variety of works of art were made by a man from minerals and stones containing silicon.The healing properties of this element have been described by scientists of antiquity and been used throughout the history of mankind.They laid out the wells for drinking water storage for products used in everyday life and in medicine.The powder obtained by grinding was applied to the wounds.Particular attention was paid to the water, which insisted in a pot made of compounds containing silicon.Chemical element interacted with her staff, which allows to destroy a number of pathogenic bacteria and microorganisms.And that's not all industries where we are considering the substance is very, very claimed.The structure of the silicon causes its versatility.
Properties
To learn more about the characteristics of the substance must be considered, taking into account all the possible properties.Plans chemical element silicon includes physical properties, electrical performance, the study compounds and reaction conditions for their passage, and so on. D. Silicon in crystalline form has a dark gray color with a metallic sheen.Face-centered cubic lattice of a resemblance to carbon (diamond), but due to the greater length of the connections is not as robust.Plasticity makes it heat up to 800 ° C, in other cases, it remains fragile.The physical properties of silicon make it truly unique substance: it is transparent to infrared radiation.Melting point - 1 410 0 C, the boiling - 2600 0 C, the density under normal conditions - 2330 kg / m3.The thermal conductivity is not constant for various samples it is accepted in the approximate value of 25 0C.The properties of the silicon atom allow its use as a semiconductor.Such applications are most in demand in today's world.The magnitude of the electrical conductivity of the composition is affected and the silicon elements which are in conjunction with them.Thus, for enhanced electron conductivity used antimony, arsenic, phosphorus, for holey - aluminum, gallium, boron and indium.When creating devices with silicon is used as a guide surface treatment with the agent, which affects the operation of the apparatus.
properties of silicon as an excellent conductor widely used in modern instrumentation.This is especially significant in the production of its use of sophisticated technology (such as advanced computing devices, computers).
Silicon: characteristic chemical element
Most of tetravalent silicon, also found communication in which it can be set to two.Under normal conditions it maloaktiven has strong bonds at room temperature can only react with fluorine in the gaseous aggregate state.This is due to the blocking effect Dioxide surface film, which is observed in the interaction with ambient oxygen or water.To stimulate the reactions necessary to use a catalyst: the temperature rise is ideal for a substance such as silicon.Chemical element reacts with oxygen at 400-500 0 C, resulting Dioxide film increases, the process of oxidation.When temperature is raised to 50 0C observed reaction with bromine, chlorine, iodine, thereby forming volatile tetrahalides.Since silicon does not interact acids, elimination of a mixture of hydrofluoric and nitric acid, wherein any alkali in a heated state is a solvent.Silanes produced only by decomposition of silicide to react with hydrogen, it does not enter.The greatest strength and chemical passivity of different compounds with boron and carbon.High resistance to alkalis and acids have nitrogen compound, which occurs at temperatures above 1000 0C.Silicides are obtained by reaction with metals, in which case an additional element independent from the valence which shows silicon.Formula substance formed with the participation of the transition metal, is resistant to acids.The structure of the silicon atom directly affect its properties and the ability to interact with other elements.The formation of relationships in nature, and when exposed to the substance (in laboratory, industrial environment) differs significantly.Silicon structure assumes its reactivity.
Structure Diagram of the structure of the silicon atom has its own characteristics.The charge of the nucleus 14, which corresponds to the number in the periodic system.The number of charged particles: protons - 14;electrons - 14;neutrons - 14. The circuit structure of the silicon atom is as follows: Si +14) 2) 8) 4. At the last (external) level there are 4 electrons that determines the degree of oxidation with a "+" or "-".Silicon oxide has the formula SiO2 (valence of 4+), volatile hydrogen compound - SiH4 (valence of -4).A large amount of silicon atoms can in some compounds have a coordination number of 6, for example, when combined with the fluorine.Molar mass - 28, the radius of an atom - 132 pm, the configuration of the electron shell: 1S22S22P63S23P2.
Application
surface or completely doped silicon is used as a semiconductor in the creation of many, including high-precision, devices (such as solar cells, transistors, rectifiers, and so on. D.).Ultra-pure silicon is used to create solar cells (energy).Monocrystalline kind used for the manufacture of mirrors and a gas laser.Among the compounds of silicon of the glass, tiles, pottery, porcelain and earthenware.The variety of types of goods produced is difficult to describe, their exploitation occurs in everyday life, in art and science, in the workplace.The resulting cement is the raw material for creating mixes and brick finishing materials.Spreading oils, lubricants based on silicone compounds can significantly reduce friction in the moving parts of many mechanisms.Silicides due to the unique properties in combating aggressive media (acids, temperatures) are widely used in industry.Their electric, nuclear and chemical parameters take into account the experts on complex productions, plays no small role and structure of the silicon atom.
We have listed the most high-tech and advanced to date application.The most common, which is produced in large quantities Technical silicon is used in several ways:
- as raw material for the production of a pure substance.
- for alloying in the steel industry: the presence of silicon increases the refractoriness, improves resistance to corrosion and mechanical strength (in excess of this element, the alloy can become too brittle).
- As a deoxidizer for removing excess oxygen from the metal.
- Raw materials for the production of silane (silicon compounds with organic substances).
- For the production of hydrogen from silicon-iron alloy.
- Manufacturing solar panels.
The significance of the substance for normal functioning of the human body.Silicon structure, its properties are defined in this case.This oversupply of, or lack of it leads to a serious illness.
In humans
medicine for a long time using silicon as a bactericidal and antiseptic.But with all the benefits of outdoor use this element must be constantly renewed in the human body.The normal level of its content will improve life in general.In the event of a lack of more than 70 trace elements and vitamins they are not digested by the body, which is significantly lower resistance to a variety of diseases.The highest percentage of silicon is observed in the bones, skin, tendons.
