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Chemistry can be defined as the subject matter of chemists.
T. L. Brown, G. Y. Lemay

In the beginning there was a word - “al hemi”, or alchemy. It goes back to the Egyptian hieroglyph "khmi", meaning black (fertile) land. The same hieroglyph also denoted Egypt itself, the place where alchemy, which was often called “Egyptian art,” may have originated. The term first appears in the manuscript of Julius Firmicus (IV century AD). J. Liebig wrote about alchemy that it “has never been anything other than chemistry.”

The next word was “iatrochemistry” - a direction in natural science and medicine that appeared in the 16th century. It assigned the main role in the occurrence of diseases to disturbances in chemical processes in the body and set the task of finding chemical means of treating them. The origin and development of iatrochemistry, which became most widespread in Germany and the Netherlands, is associated with the activities of Paracelsus (1493–1541), as well as the physician and anatomist F. Boe (1614–1672), who formulated its main principles and opened the first chemical laboratory for analyses. Representatives of iatrochemistry paid attention to the study of digestive processes, as well as gonads and other glands; distinguished between “acid” and “alkaline” diseases. Iatrochemistry in the second half of the 18th century ceased to exist as a direction in medicine, but gave rise to experimental chemistry.

Most chemists of the 16th–18th centuries had medical training and served as pharmacists. Further, since synthetic chemistry did not yet exist, substances for drugs were extracted in their natural state from minerals and plants, and this required methods of analysis, separation and purification of substances. Analytical chemistry is developing. Then military interests and consumer demands gave rise to other branches of chemistry.

Now chemistry consists of five major sections. These are analytical chemistry, inorganic chemistry, organic chemistry, biochemistry, physical chemistry and technical chemistry. And then they divide, forming a hundred different chemistries. Such diversity makes us think that the time has come for chemistry to add, not divide.

Academician Yu. A. Kosygin wrote: “By the end of the 20th century, science seemed to be divided into layers... A specialist often isolated himself in his layer, getting carried away by the details within it... This created a narrowness of scientific thinking, oblivion of the integrity of the world, the problems of which can can only be solved by joint work in different specialties or their interpenetration. The division into specialties creates an atmosphere of mustiness and helplessness.”

Thus, the first task of the article is to show the absurdity of such a division in relation to chemistry. Sections are taken from chemical encyclopedias, reviews, web pages of universities and research institutes, titles of textbooks and journals. The second task is to familiarize neophytes with the variety of chemical solutions to everyday problems. And the third task. It is unpleasant for the author, as a professional, to hear at all corners: “grown without chemicals,” “the product does not contain chemicals,” and other strange slogans. Where can you go without chemicals?

Analytical chemistry- development of methods for determining the chemical composition of a substance. It arose earlier than other chemical sciences, and until the end of the 18th century, chemistry was defined as the science that studies the chemical composition of substances. Historically, this is the first scientific chemistry proper.

Agrochemistry- the science of chemical processes in soil and plants, mineral nutrition of plants, the use of fertilizers and chemical soil reclamation agents. Includes determination of the content of chemical elements, proteins, amino acids, vitamins, fats, carbohydrates in soils and plants; establishing the mechanical and mineralogical composition of soils, their content of organic matter (humus), salts, algae, microorganisms, etc. Studies the effect of fertilizers on plants and soil. Many techniques of agrochemistry have been included in farming practice since ancient times. Thanks to the creation of a new branch of agrochemistry - the chemistry of pesticides - it became possible not only to improve plant nutrition, but also to influence (with the help of growth regulators) their development, as well as protect them from diseases, insects, mites, nematodes and other pests. The discovery of selective herbicides had a huge impact on agricultural chemistry. The destruction of weeds with their help made it possible to improve the growth conditions of plants and use fertilizers more efficiently, since they are not spent on feeding weeds.

Analytical chemistry of elements. The Institute of Geochemistry and Analytical Chemistry of the Russian Academy of Sciences (GEOKHI, Moscow) publishes a series of monographs, of which there are already over 50, and ideally there should be 109 - according to the number of known chemical elements.

Astrochemistry studies chemical reactions between atoms, molecules and dust grains in the interstellar medium, including the phases of star and planet formation. Helium synthesis can be considered the beginning of all reactions in nature, the root cause of life, light, heat and meteorological phenomena on Earth. The birth of chemical elements is a function of stars. Up to and including iron, they are born in thermonuclear fusion processes in the depths of countless suns. From cobalt onwards, they are created during supernova explosions through neutron-rich nuclei, followed by a series of beta decays. Radio astronomers have shown that dark interstellar clouds contain many complex molecules (methanol, carbon monoxide, formaldehyde, ethanol, hydrocyanic acid, formic acid and others). Molecular radio astronomy has made it possible to identify all these molecules by their rotational spectra in the microwave region.

Bioinorganic chemistry studies complexes of biopolymers or low molecular weight natural substances with metal ions present in living organisms (Na +, K +, Ca 2+, Mg 2+, Fe 2+). Explores the role of these ions in performing the biological functions of enzymes. Practical use associated with the synthesis of metal-containing drugs.

Bioorganic chemistry studies the relationship between the structure of organic substances and their biological functions. Objects of research: biopolymers, vitamins, hormones, antibiotics and others. It was formed at the intersection of biochemistry and organic chemistry. Bioorganic chemistry is associated with practical problems in medicine, agriculture, chemical, food and microbiological industries.

Biochemistry studies the chemical substances that make up organisms, their structure, distribution, transformations and functions. It would seem that this science should be a branch of organic chemistry, but numerous branches of biochemistry have turned it into a separate direction. The first synthesis of the natural substance urea in 1828 destroyed the idea of ​​" vitality", participating in the formation of substances by the body. The introduction of ideas and methods of physics and chemistry into biology, as well as the desire to explain such biological phenomena as heredity, variability or muscle contraction by the structure and properties of biopolymers, led in the mid-20th century to the separation of molecular biology from biochemistry. The needs of the national economy for obtaining, storing and processing various types of raw materials led to the development of technical biochemistry. At the end of the 20th and beginning of the 21st centuries, biochemistry became the leading chemical field; in any case, most Nobel Prizes in chemistry are awarded specifically for biochemical work.

Galurgy- section of chemical technology for the production of mineral salts. Galurgy in the narrow sense includes the processing of natural salts. The raw materials for halurgical production are sea water, sea salt deposits, as well as lake and underground brines. Applied tasks - design of potash, salt and sulfate enterprises; design of enterprises for the extraction and processing of mining chemical raw materials: sodium sulfate, phosphorite, magnesium-containing raw materials and other natural salts.

Geochemistry studies the chemical composition of the Earth, the prevalence of chemical elements and their stable isotopes in it, patterns of distribution of chemical elements in various geospheres, laws of behavior, combination and migration of elements in natural processes. Geochemistry was historically formed as the chemistry of elements in geospheres and in many ways continues to remain so. This was justified in the times of Fersman and Vernadsky. But the properties of substances are the properties of phases. The same element can be present in different phases and itself form many phases with very different properties (remember, for example, the carbon phases). In the 20th century, phase analysis methods appeared. Therefore, the further development of geochemistry is the chemistry of phases in geospheres. Bulk elemental analysis of geological samples should be supported by phase analysis. Otherwise, there is now an unjustified leap across the structural level of organization of matter: from a chemical element, bypassing the mineral phase, to rock and geological body.

Hydrochemistry studies the chemical composition of natural waters and the patterns of its changes under the influence of physical, chemical and biological influences. The task is to establish the chemical composition of the main elements of the ecosystems of the oceans and seas, the processes of their biogeochemical transformation and evolution.

Histochemistry- a branch of histology that studies the localization of various chemicals and the products of their metabolism in tissues. Some staining methods can detect certain chemicals in cells. Differential staining of fats, glycogen, nucleic acids, nucleoproteins, some enzymes and other chemical components of the cell is possible. The contribution of histochemistry to the study of the chemical composition of tissues is constantly increasing. Dyes, fluorochromes and enzymes have been selected that can be attached to specific immunoglobulins (antibodies) and, by observing the binding of this complex in the cell, cellular structures can be identified. This area of ​​research is the subject of immunohistochemistry. The use of immunological markers in light and electron microscopy contributes to expanding knowledge of cell biology, as well as increasing the accuracy of medical diagnoses.

Immunochemistry studies the chemical basis of immunity. The main problems: the structure and properties of immune proteins - antibodies, natural and synthetic antigens, as well as the identification of patterns of interaction between these main components of immunological reactions in different organisms. Immunochemical methods are also used for applied purposes, in particular in the isolation and purification of the active principles of vaccines and serums.

Quantum chemistry. This branch of chemistry based on quantum mechanics examines the structure and properties of chemical compounds, reactivity, kinetics and mechanisms of chemical reactions. Due to the complexity of objects, approximate calculation methods are used. Computer chemistry is inextricably linked with quantum chemistry - a discipline that uses mathematical methods to calculate molecular properties, the amplitude of the probability of finding electrons in atoms, and modeling molecular behavior.

Colloid chemistry- science of disperse systems and surface phenomena. This is where the now popular nanotechnology originates. Colloidal systems are both human and aspic. Since the particles of the dispersed phase and their surrounding medium have a large interface, surface phenomena have a decisive influence on the properties of the system as a whole. The goal of the research is to control the formation, properties and destruction of dispersed systems and boundary layers by regulating intermolecular interactions at phase boundaries. This is achieved with the help of surfactants that can spontaneously concentrate on the surface of dispersed phase particles.

Computational chemistry- see quantum chemistry.

Cosmetic chemistry. Its subject is means and methods of improving a person’s appearance. There are medical and decorative cosmetics. The expression “skin is the largest organ” is well known, and one cannot help but think about how it functions, how the substances that we apply to its surface act, and what consequences this or that effect will lead to. Cosmetic chemistry is looking for answers to these questions.

Cosmochemistry- the science of the chemical composition of cosmic bodies, the laws of abundance and distribution of chemical elements in the Universe, the processes of combination and migration of atoms during the formation of cosmic matter. Cosmochemistry studies predominantly “cold” processes at the level of atomic-molecular interactions of substances, while “hot” nuclear processes in space - the plasma state of matter, nucleogenesis (the process of formation of chemical elements) inside stars - are dealt with by physics. The development of astronautics has opened up new opportunities for cosmochemistry. This is a direct study of lunar rocks with the participation of astronauts or as a result of taking soil samples by automatic devices and delivering them to Earth. Automatic descent vehicles made it possible to study matter and the conditions of its existence in the atmosphere and on the surface of other planets of the Solar System and asteroids, in comets. Due to extreme conditions in outer space, processes occur and states of matter occur that are unusual on Earth. In interstellar space, atoms and molecules of many elements are found in extremely small concentrations, as well as minerals (quartz, silicates, graphite and others) and, finally, various complex organic compounds are synthesized from the primary solar gases H, CO, NH 3, O 2, N 2 , S and other simple compounds under equilibrium conditions with the participation of radiation.

Cryochemistry studies chemical transformations of substances at low temperatures. The main tasks are to obtain compounds that are chemically unstable under normal conditions, to determine the lower temperature limits of the chemical activity of substances, and to develop technological processes using low temperatures. Cryotechnology products - chemical reagents, enzymes, sorbents, medicinal substances, resistors, composites, pigments, catalysts, electrode and piezomaterials, porous ceramics, powders for glass melting and growing single crystals.

Crystal chemistry studies the laws of atomic arrangement and types of symmetry in crystalline solids, as well as defects in their structure. The central concept of crystal chemistry is crystal structure. Over 120,000 crystal structures have been determined (about 40,000 inorganic, more than 80,000 organic) - from simple substances to proteins and viruses. The source of data on structures are diffraction research methods: X-ray diffraction analysis, electron diffraction, neutron diffraction, Mössbauerography. The reasons for the formation of a particular crystalline structure are determined by the general principle of thermodynamics: the most stable structure is the one that, at a given pressure and temperature, has minimal free energy. The 230 space symmetry groups discovered by E. S. Fedorov represent a natural law of nature that does not have a mathematical expression (along with the Periodic System of D. I. Mendeleev).

Laser chemistry studies chemical processes stimulated by laser radiation. The high monochromaticity of laser radiation allows one to selectively excite molecules of one type, while molecules of other types remain unexcited. The ability to focus laser radiation allows energy to be introduced locally, into a certain region of the volume occupied by the reacting mixture. Laser effects on chemical reactions can be thermal and photochemical. Laser ophthalmology and microsurgery are ultimately the same laser chemistry, but in the service of medicine.

Timber chemistry studies Chemical properties wood and methods of its industrial processing in order to extract as many useful substances as possible. Pulp and paper production ranks first in terms of volumes of processed raw materials and finished products in the forest industry. It consumes pulpwood and firewood (80%), logging and woodworking waste (chips, sawdust - 20%) for the production of cellulose, wood pulp and the production of paper and cardboard from them. Nitration of cellulose with concentrated nitric acid in the presence of concentrated sulfuric acid produces trinitrocellulose, called pyroxylin, which is used in the production of smokeless powder, so you should look for an ammunition factory near the pulp and paper mill. Hydrolysis production uses sawmill and woodworking waste as raw materials. Initially, coniferous wood was subjected to hydrolysis, producing 160–180 liters of ethanol per 1 ton of absolutely dry raw material (later they also began to produce an additional 35–40 kg of feed yeast from post-alcohol stillage). Then enterprises with a furfural-yeast profile (70–80 kg of furfural and 100 kg of yeast per 1 ton of dry plant waste) and a pure yeast profile appeared. The waste from this production is hydrolyzed lignin (30–40% based on absolutely dry raw materials), which is used as boiler fuel, as well as for the production of coals for various purposes, fertilizers, acetic and oxalic acids, phenols, and fillers for polymer materials. However, most often this lignin remains in the form of waste dumps that no one needs. There is also tanning-extract production - a source of tanning substances. To produce them, the bark of willow, spruce, larch, bergenia leaves, oak or chestnut wood is used. Rosin is also obtained from resin. Another direction is pyrolysis production, the production of charcoal from wood by heating it without air access in special steel retorts and furnaces.

Magnetochemistry studies the connection between the magnetic and chemical properties of substances, the influence of magnetic fields on chemical processes. Spin chemistry as a branch of magnetochemistry is unique: it introduces magnetic interactions into chemistry. Being negligible in energy, magnetic interactions control chemical reactivity and write a new, magnetic “script” for the reaction. The production of molecular magnets, multispin molecules containing unpaired electrons, and spin labels can also be classified as spin chemistry.

Medicinal chemistry includes aspects of biology, medicine, pharmaceuticals. She is involved in the discovery, design, identification and production of biologically active compounds, studying their metabolism, interpreting their mode of action at the molecular level and generating structure-activity relationships. Thus, having started with medicine in the 16th century, chemistry is returning to it, despite some skepticism of doctors. Suffice it to say that 70% of drugs are products of synthetic chemistry, and the remaining 30% are phytochemicals.

Metallurgy- a field of science and technology that covers the processes of obtaining metals from ores or other substances, changing the chemical composition, structure and properties of metal alloys. Metallurgical processes are also used to produce non-metallic materials, including semiconductors. There are pyrometallurgy (the use of processes taking place at high temperatures), hydrometallurgy (the extraction of metals by chemical reactions in aqueous solutions) and electrometallurgy (the use of electrolysis).

Mechanochemistry studies the chemical transformations of substances during deformation, friction, and shock compression. Plastic deformation of a solid usually leads to the accumulation of defects in it that change its physicochemical properties, including reactivity. This is used in chemistry to speed up reactions, reduce the temperature of processes and other ways to intensify chemical reactions in the solid phase. Using the mechanochemical method, polymers are destroyed, intermetallic compounds and ferrites are synthesized, amorphous alloys are obtained, and powder materials are activated.

Nanochemistry– chemistry and technology of objects whose dimensions are about 10–9 m (clusters of atoms, macromolecules). When it comes to the development of nanotechnology, three directions are in mind: the production of electronic circuits (including volumetric ones), the elements of which are comparable in size to atoms; development and production of nanomachines; manipulation of individual atoms and molecules and assembly of macro-objects from them. The place of nanochemistry in nanotechnology is the synthesis of nanodispersed substances and materials, regulation of chemical transformations of nanometer-sized bodies, prevention of chemical degradation of nanostructures, methods of treating diseases using nanoparticles.

Neurochemistry- a branch of biochemistry that studies the chemical and cellular mechanisms of the nervous system. Neurochemistry is divided into general, which studies the chemical properties of the nervous system without connection with specific physiological activity, and functional (particular), which studies the chemical and molecular mechanisms of the nervous system in the process of implementing a particular physiological function. Understanding the chemical mechanisms of brain activity is not just one of the tasks of biology, it plays an important role in a person’s desire to understand himself as an individual, to understand his place on Earth. Therefore, neurochemistry is one of the most complex, modern and rapidly developing areas of biochemistry and neurobiology. It is closely related to such areas of biology as the morphology and physiology of the nervous system, molecular biology and genetics, as well as to clinical disciplines, in particular neuropathology and psychiatry.

Inorganic chemistry studies chemical elements and the simple and complex substances they form (except for organic carbon compounds). Provides the creation of materials of the latest technology. The number of inorganic substances is approaching 400 thousand.

Organic chemistry studies the compounds of carbon with other elements - the so-called organic compounds and the laws of their transformations. By the end of the 20th century, their number exceeded 10 million. The synthesis of numerous organic substances led to the creation of new industries - synthetic dyes, polymers, artificial liquid fuels and food. It was possible to synthesize vitamins, hormones, and enzymes. The diversity of organic compounds is largely due to isomerism - the ability of compounds with the same composition and mass to differ in structure, physical and chemical properties. Organic chemistry is divided into a huge number of areas.

Petrochemistry studies the composition, properties and chemical transformations of oil and natural gas components, as well as their processing processes.

Organic geochemistry studies the chemical and isotopic composition of organic substances contained in rocks, their evolution during geological history, patterns of distribution, as well as the role of organic matter in the processes of migration of chemical elements in the earth's crust, the formation of deposits of uranium, copper, vanadium, germanium, and molybdenum. This section of chemistry studies the biochemical compounds starting from organic matter (carbohydrates, proteins, lignin) and the products of their transformation in external geospheres (humus, sapropel, fossil coals, oil shale, oil) under the influence of bacterial life, temperature, pressure and other factors. The geochemistry of oil and coal was divided into two independent scientific directions. Organic geochemistry is closely related to organic cosmochemistry in terms of the study of the organic matter of cosmic bodies.

Organic synthesis studies ways and methods of artificial creation of organic compounds. In 1828, F. Wöhler was the first to synthesize an organic substance from an inorganic substance outside a living organism - he rearranged ammonium cyanate into urea when heated in an aqueous solution. The goals of organic synthesis are to obtain substances with valuable physical, chemical and biological properties or to test theoretical predictions. Modern organic synthesis is multifaceted and makes it possible to obtain almost any organic molecules.

Pathochemistry studies the chemical mechanisms of pathological processes. For example, the problem of organ rejection during transplantation is largely a problem of pathochemistry.

Petrochemistry studies the distribution of chemical elements in rocks and rock-forming minerals.

Peturgy - production of glass-crystalline materials and products from rock melts (for example, basalts and diabases) and industrial waste (for example, slag and ash) by casting. Petrurgical materials are preferable to metallurgical ones, since they are stable in the oxidizing atmosphere of the Earth and involve the direct use of raw materials without isolating pure components. Petrurgical production produces pipes, plates, trays to protect the working surfaces of bunkers, chutes, assemblies of mining and processing, metallurgical and power equipment; acid-resistant tiles and shaped parts for the chemical industry; lining of ball mills, facing materials and other products operating under conditions of exposure to acids, alkalis or abrasive bulk materials and pulps, as well as basalt (stone) fiber.

Pegniochemistry. Chemists also joke: what can you do if hot and cold glass in the laboratory look the same! Sociologists conducted a survey of the population. All respondents were asked two questions: 1) how do you feel about chemical fertilizers? 2) what is your grade in chemistry at school? It turned out: 1) 90% of Russians are categorically against chemical fertilizers; 2) the remaining 10% had a grade of “5” in chemistry. The Institute of Pegniochemistry of the Russian Academy of Sciences, perhaps, will appear when we understand the unity of nature and the dead end of the endless division of knowledge, and laugh at the art of dividing and not conquering.

Chemical folklore undoubtedly belongs to the field of pegniochemistry.

The motor spins and turns the stirrer.
There is a three-neck burgundy solution in a flask.
Acetophenone cooks and sours.
He'll get back to normal soon.

As soon as I started distilling benzene -
The flask exploded... The pieces could not be collected.
Benzene ignited and the robe caught fire.
The neighbor noticed something out of place.

Food chemistry. Its goal is to create high-quality food products and analytical methods in the chemistry of food production. This is one of the most ancient experimental branches of chemistry since the advent of yeast bread. The chemistry of food additives controls their introduction into food products to improve production technology, as well as the structure and organoleptic properties of products, increase shelf life, and increase biological value. These additives include preservatives, antioxidants, oxidizing agents, emulsifiers, stabilizers, dyes, flavoring agents and aromas, taste and smell intensifiers, vitamins, microelements, amino acids, and spices. The creation of artificial food is also a subject of food chemistry. These are products that are made from proteins, amino acids, lipids and carbohydrates, previously isolated from natural raw materials or obtained by directed synthesis from mineral raw materials. Food additives, as well as vitamins, mineral acids, microelements and other substances give the final product not only nutritional value, but also color, smell and the desired structure. As initial components, secondary raw materials from the meat and dairy industries, seeds, green mass of plants, hydrobionts, and biomass of microorganisms, such as yeast, are used. Of these, high molecular weight substances (proteins, polysaccharides) and low molecular weight substances (lipids, sugars, amino acids and others) are isolated. Low molecular weight nutrients are also obtained by microbiological synthesis from sucrose, acetic acid, methanol, hydrocarbons, enzymatic synthesis from precursors and organic synthesis (including asymmetric synthesis for optically active compounds). There are synthetic foods obtained from synthesized substances, for example, diets for therapeutic nutrition, combined products from natural products with artificial food additives, such as sausages, minced meat, pates, and analogues of food products that imitate any natural products, - say, black caviar.

Plasmochemistry studies chemical processes in low-temperature plasma. Low-temperature plasma is considered to be one with a temperature of 10 3 –10 5 K and a degree of ionization of 10 –6 –10 –1, obtained in electric arc, high-frequency and microwave gas discharges, in shock tubes, adiabatic compression installations and other methods. In plasma chemistry, it is important to separate low-temperature plasma into quasi-equilibrium, which exists at pressures on the order of atmospheric pressure and above, and nonequilibrium, which is obtained at a pressure of less than 30 kPa and in which the temperature of free electrons significantly exceeds the temperature of molecules and ions. This division is due to the fact that the kinetic patterns of quasi-equilibrium processes are determined only by the high temperature of the interacting particles, while the specificity of nonequilibrium processes is due to the large contribution of chemical reactions initiated by “hot” electrons. An example of plasma-chemical technology is: synthesis of acetylene from natural gas (electric arc furnace, 1600°C): 2CH 4 = C 2 H 2 + ZH 2.

Applied chemistry. Behind this neutral word lies the most sinister chemistry - chemistry for war. Serves mainly the needs of the military-industrial complex.

Radiochemistry studies the behavior of radioactive elements, methods of their isolation and concentration. This is the scientific basis for obtaining highly active materials and regenerating nuclear fuel, and developing methods for using radionuclides.

Radiation chemistry - see high energy chemistry.

Sonochemistry studies chemical reactions under the influence of ultrasound; This is a type of mechanochemistry that manifests itself in a liquid: elastic waves act on substances to change their structure and properties. The main tool of sonochemistry is cavitation, the formation of a mass of pulsating bubbles in a liquid medium. The pressure in them increases to 800 MPa, the temperature (according to theoretical estimates) - to 7400 K, electrical discharges are formed, ionization occurs, and the phenomenon of sonoluminescence occurs - sound turns into light. Estimates show that during sonoluminescence, energy concentration occurs a trillion times, that is, by 12 orders of magnitude! This is where one of the tempting possibilities of ultrasound in liquid originates - “bubble thermonuclear fusion”.

Spin chemistry - see magnetochemistry.

Stereochemistry studies the spatial structure of molecules and its influence either on chemical properties (static stereochemistry) or on the rate and direction of reactions (dynamic stereochemistry).

Forensic chemistry - part of applied, predominantly analytical chemistry in the broad sense of the word. This is an almost immense area in terms of the abundance and variety of problems it solves, because every chemical research, in essence, can be a method of forensic chemical examination. It includes the examination of air, water, soil, food and flavor supplies, consumer goods, human secretions and excreta, suspicious blood and seminal stains, various technical preparations, handwritten and printed documents, raw and processed medicinal substances. But even with a narrow interpretation, when forensic chemistry means that part of analytical chemistry that is specifically concerned with the discovery of poisons in intentional and unintentional poisonings, the field of forensic chemistry remains very vast, since the very concept of “poison” seems extremely flexible. The connection of forensic chemistry not only with toxicology and pharmacology, but also with therapy and physiology is obvious. To finally resolve issues that arise during forensic chemical studies of alleged poisonings, one cannot limit oneself to indications of the presence or absence of certain poisons, but it is necessary to establish or exclude a dependence or even a causal relationship between the poison found and the results noted during the autopsy of the corpse, to find out - since the results may be due to changes occurring after death; it is finally necessary to resolve the extremely important question of whether the discovered poison or the isolated toxic substance can cause exactly the same symptoms that were observed during life. Here the doctor and the chemist complement each other.

Supramolecular chemistry means chemistry, describing complex formations that are the result of the association of two (or more) chemical particles bound together by intermolecular forces. Its main objects are supramolecular devices and assemblies. Devices are structurally organized systems, the molecular components of which have certain electro-, ion-, photo-, thermochemical and other properties. Clathrate chemistry is the most advanced part of supramolecular chemistry.

Thermochemistry studies thermal phenomena accompanying chemical reactions. Thermochemical data (values ​​of the heat of formation and combustion of chemical compounds, thermal effects of reactions) are used in chemical technology, when calculating the heat balances of processes. They also serve as the calculation basis of chemical thermodynamics.

Technical chemistry. This includes textile chemistry, material processing chemistry, glass chemistry (and this is the optical industry - the “eyes” of microscopists, military officers and astronomers), chemical aspects of the economy. Elements of technical chemistry can be found in the 15th-17th centuries. In the mid-15th century, blower forge technology was developed. The needs of the military industry stimulated work to improve gunpowder production technology. Fundamental works were published on the production of metals and various materials used in construction, glass making, fabric dyeing, food preservation, and leather tanning. With the expansion of consumption of alcoholic beverages, distillation methods were improved and new distillation apparatuses were designed. Numerous production laboratories appeared, primarily metallurgical ones. Among the chemical technologists of that time we can mention Vannoccio Biringuccio (1480–1539), whose classic work On Pyrotechnics was published in Venice in 1540 and contained ten books. They dealt with mines, testing minerals, preparing metals, distillation, the art of war, and fireworks. Another famous treatise, On Mining and Metallurgy, was written by George Agricola (1494–1555).

Topochemistry studies solid-phase reactions occurring in certain areas of a solid. The path of topochemistry goes from roasting mineral raw materials to molecular beam epitaxy (oriented growth of one crystal on the surface of another), which is actively used in microelectronics. The oriented growth of a crystal inside the volume of another is called endotaxy. Endotaxy is observed, for example, during crystallization and corrosion.

Coal chemistry studies the origin, composition, structure, properties of solid fossil fuels, as well as methods of their processing. The main task of coal chemistry is the development of technologies for producing new carbon materials and adsorbents from coal, its processed products and other carbon-containing raw materials.

Pharmacochemistry (pharmacy) studies the preparation of medicinal substances that act on the human and animal body. Testing their safety is also one of the tasks of pharmacochemistry. Of the 400 chemical compounds proposed as medicines, only one is accepted after testing!

Femtochemistry - the ability to observe the progress of elementary chemical reactions in the femtosecond time range (10–15–10–12 s). These times are much shorter than the period of vibrations of atoms in molecules (10–13–10–11 s). Thanks to this relationship of times, femtochemistry “sees” the chemical reaction itself - how atoms move in time and space when reactant molecules are converted into product molecules. This is a direct way to study the mechanisms of chemical reactions, and therefore a way to control reactions. The successes achieved using femtosecond pulses led to the discovery of another science - femtobiology.

Physical chemistry - the science of general laws that determine the structure and chemical transformations of substances under changing external conditions. They say that chemists work with dirty substances using clean methods, physicists work with dirty substances using dirty methods, and physical chemists use dirty methods with dirty substances, that is, they study chemical phenomena using physical methods. At first it was weight and volumetric analyses, the sense of taste and smell, measurement of heat and color. Then R.V. Bunsen and G. Kirchhoff came with spectral analysis, and off we went. An achievement at the turn of the century was the recognition of the fact that the world of substances is more unbalanced than equilibrium. In addition, in physical chemistry the laws of arithmetic are often violated. Here is a typical example: 50 ml H 2 O + 50 ml C 2 H 5 OH = 96 ml vodka + heat.

Physical organic chemistry pays special attention to the study of the mechanisms of organic reactions, as well as the quantitative relationship between the chemical structure of organic compounds, their properties and reactivity. One of the achievements is the discovery and practical use of stable radicals, which have found application in various fields of science and technology as spin labels, in which the unpaired electron serves as a source of the electron paramagnetic resonance (EPR) signal.

Phytochemistry. Her concern is the creation of highly effective medicines based on substances of plant origin. Another direction is environmentally friendly plant protection products. The drug journey begins in the laboratory of either an organic chemist or a phytochemist. The first creates compounds that have not yet been studied, the second releases substances from plants. The created or isolated substances are then transferred to a pharmacologist. It determines whether these substances have the desired effect. To find the active compound, two methods are used. The first is screening, that is, sifting - sorting through the available substances without assuming what specific structure the substance needs. Screening was first used at the beginning of the 20th century by P. Ehrlich to obtain antisyphilitic drugs based on organic arsenic compounds. The second is directed synthesis: the researcher gradually accumulates material showing which chemical radicals or other structures are responsible for this or that type of action. Natural molecules of plant origin serve as models for the synthesis of useful compounds. An example of such a compound is salicylic acid, isolated from willow bark. On its basis, such a popular medicine as aspirin (acetylsalicylic acid) was created. Currently, despite the enormous successes of synthetic chemists, more than a third of medicines are obtained from plants. The structure of many of them is so complex (vinblastine, cardiac glycosides, cocaine, reserpine, quinine, colchicine, pilocarpine) that plants will be their only source for a long time.

Photochemistry studies reactions excited by light. Practical photochemistry - photography, production of printing plates and microcircuits using photolithography methods, photochemical synthesis (for example, caprolactam). The most significant natural photochemical process for the Earth is photosynthesis, the conversion of the energy of sunlight by green plants and photosynthetic microorganisms into the energy of chemical bonds of organic substances.

Chemical Technology is the science of methods and means of rational chemical processing of raw materials, semi-finished products and industrial waste. Inorganic chemical technology includes the processing of mineral raw materials (except metal ores), the production of acids, alkalis, and mineral fertilizers. Organic chemical technology - processing of oil, coal, natural gas and other fossil fuels, producing synthetic polymers, dyes, medicines and other substances.

Chemical physics studies the electronic structure of molecules and solids, molecular spectra, elementary acts of chemical reactions, combustion and explosion processes. It was formed in the 20s of the 20th century in connection with the development of quantum mechanics and the use of its concepts in chemistry. The boundary between chemical physics and physical chemistry is conventional, and the term was introduced by the German chemist A. Eiken in 1930. One of the achievements of chemical physics is the theory of branched chain reactions.

Chemical weapons- chemical warfare agents, means of their use (missiles, shells, mines, aircraft bombs and others), neutralization and protection. The use of chemical weapons is prohibited by the Geneva Protocol of 1925, which has been ratified by over 100 states. However, its development, production and accumulation in some countries still continues.

High Energy Chemistry studies chemical reactions and transformations that occur in matter under the influence of non-thermal energy. Carriers of non-thermal energy acting on matter are accelerated electrons and ions, fast and slow neutrons, alpha and beta particles, positrons, muons, pions, atoms and molecules at supersonic speeds, quanta of electromagnetic radiation, as well as pulsed electric, magnetic and acoustic fields. High-energy chemistry processes are distinguished by time stages into physical, occurring in femtoseconds or less, and during this time, non-thermal energy is distributed unevenly in the medium and a “hot spot” is formed, physicochemical, during which nonequilibrium and inhomogeneity appear in the “hot spot” ", and, finally, chemical ones, in which the transformations of matter obey the laws of general chemistry. As a result, ions and excited states of atoms and molecules are formed that at room temperature cannot arise due to equilibrium processes.

Chemistry of macromolecular compounds- a branch of organic chemistry, the objects of study of which are macromolecules of synthetic and natural origin, consisting of repeating monomer units or molecular groups connected by chemical bonds and containing carbon atoms, as well as oxygen, nitrogen and sulfur in the main chain. Numerous materials, including smart structures, with functional ingredients are being developed based on high-molecular compounds (polymers), which significantly expands the scope of their application. The simplest macromolecule is polyethylene:

CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -...

Chemistry of catalysis studies substances that change the rate of chemical reactions. The catalyst is not in a stoichiometric relationship with the products and is regenerated after each cycle of converting reactants into products. Despite the emergence of new methods of activating molecules (plasma chemistry, radiation and laser effects, and others), catalysis is the basis of chemical production (the relative share of catalytic processes is 80–90%).

"Chemistry" to which you can send. In 1963, the Central Committee of the CPSU adopted a course for the chemicalization of the national economy. The slogan became popular: “Communism is Soviet power plus electrification of the entire country, plus chemicalization of the national economy.” On the chemicalization front, the shock corps was made up of paroled prisoners. In this regard, people called “chemistry” parole, probation with mandatory involvement in work. Includes transfer to a special commandant's office, where the prisoner is required to live in a special dormitory and work at a specified enterprise. The new humane Criminal Code provides for alternative types of punishment for minor crimes: fines, community service at the place of residence.

Chemistry of silicates- salts of silicic acids. The role of cations in silicates is played by elements of the second, third and fourth periods of D.I. Mendeleev’s table. In nature, silicates are present in the form of minerals and are part of most rocks that make up the bulk of the earth's crust. Closely related are ceramics, products and materials obtained by sintering clays and their mixtures with mineral additives, as well as oxides and other inorganic compounds.

Chemistry of natural compounds studies methods of production, structure and properties of natural bioorganic compounds of the carbohydrate class, as well as their synthetic analogues. For example, the aroma of coffee contains up to 500 different components. The chemistry of tea is also the chemistry of natural compounds. The work of the German chemist A. Bayer, who studied the structure and synthesis of indigo derivatives (indole and the synthesis of the natural dye blue indigo - this is the color of classic jeans), led to the creation of the chemistry of synthetic dyes and to the 1905 Nobel Prize “for services to the development of organic chemistry and the chemical industry thanks to work on organic dyes and hydroaromatic compounds." This was the beginning of the huge aniline dye industry.

Solid State Chemistry studies reactions involving one or more substances in the solid state. Finds application in microelectronics, synthesis of new materials (cermets, superconductors). One striking example is self-propagating high-temperature synthesis (SHS). Modern development of the SHS method has made it possible to develop technologies for the production of superhard and refractory materials, such as titanium nitride, boron carbide, titanium diboride, titanium carbide, as well as oxide materials for lining furnaces (zirconium oxide) and even high-temperature superconductors.

Chemistry of organoelement compounds- the science of the structure and transformations of compounds containing chemical bonds “element-carbon”, where “element” is any of the elements of the Periodic Table, with the exception of H, O, S, CI, Br. The main classes of organoelement compounds are organometallic, organosilicon, organoboron, organophosphorus, and organofluorine compounds. Metal-organic compounds (MOCs) contain a metal-carbon (M-C) bond in the molecule. Cyanides, carbides, and in some cases metal carbonyls, also having M-S connection, are considered inorganic compounds. Organic compounds of B, Al, Si and some non-metals are sometimes classified as MOCs. Heme is the most famous and useful natural organometallic compound - an oxygen carrier in the human body.

In the chemistry of living organisms, the role of organoelement compounds is not yet entirely clear, however, we can say with confidence that compounds of silicon, phosphorus and other elements play an important role in the life activity of living organisms standing on high level evolutionary development, in particular of humans.

Researchers are working on the synthesis of polymers with 45 elements of the Periodic Table. It turned out that B, Al, Si, Ti, Sn, Pb, P, As, Sb, Fe in combination with oxygen and nitrogen are capable of forming inorganic chains of polymer molecules with side organic and organosiloxane groups.

Applied aspects of the chemistry of organoelement compounds are aimed at creating new substances and materials for medicine (drugs, materials for prosthetics, suture threads), radio electronics (photo- and light-sensitive materials, semiconductors, ferromagnets), agriculture (plant growth stimulants, pesticides, herbicides) and other industries (catalysts, combustion regulators for motor fuels).

Cytochemistry studies the structure and functions of cells, intracellular structures and their metabolic products using chemical methods.

Electrochemistry studies the properties of systems containing mobile ions, as well as phenomena that arise at the boundary of two phases due to the transfer of charged particles. This is necessary for electrolysis, electroplating, protecting metals from corrosion and creating chemical current sources. Electric batteries, reusable chemical current sources are the everyday embodiment of electrochemistry.

Nuclear chemistry- the boundary line between nuclear physics, radiochemistry and chemical physics. Studies the relationship between the transformations of atomic nuclei and the structure of the electronic shells of atoms and molecules. Sometimes nuclear chemistry is incorrectly identified with radiochemistry. It includes the study of nuclear reactions and the chemical consequences of nuclear transformations, the chemistry of “new atoms” - positronium (Ps), muonium (Mu), the search for new elements and radionuclides, new types of radioactive decay.

The article was written based on the materials of the monograph:
Ablesimov N. E. Synopsis of chemistry: Reference and textbook on general chemistry.
Khabarovsk: Publishing house DVGUPS, 2005.

Perm was invented back in 1906: hairdresser Karl Nessler used the new method on his wife.

This kind of perm is certainly not the most beneficial method for hair, however, the result of perm is very high quality and therefore more and more women and girls are turning to beauty salons to become the owners of such desired curls.

Over the course of its long history, perms have been improved several times. In Soviet times, women were curled in such a way that they looked like lambs. This kind of chemistry looked completely unnatural, and besides, it mercilessly burned the curls. Today the method has been seriously improved.

Not every woman can boast of voluminous curls, but curls, meanwhile, give a woman’s face softness and femininity. For those who want to get a magnificent head of curly strands, a method such as perm has been invented, which helps to radically change the image and hide the imperfections of the oval of the face.

Chemistry is an auxiliary tool during styling, preparing strands for curling. Experts especially recommend it to those women who use curling irons or curlers every day. Among other things, chemistry can eliminate the problem of oily hair.

The curly effect lasts for three to four months. In this case, everything depends on the quality characteristics of the chemical composition and the individual characteristics of the hair.

Today's method perm has undergone major changes. In modern Hairdressing salons use a variety of effective products and preparations that allow them to accomplish almost any task: making curls incredibly small or large.

In fact, only the principle of hair curling, based on the structural change of the hair, has been preserved from the previous chemistry. Methods and methods have improved so much that curls are practically not injured during this procedure.

But how does the process itself happen?

Immediately before curling, the structure of keratin (hair protein) is dense and closed. Under the influence of chemistry, the bonds between molecules break down and the protein is damaged. The hair scales open up and at this time, by twisting the hair into bobbins, they can be given any shape.

The next step is fixation new form entire hairstyle. For this, a weak solution of hydrogen peroxide is used. When fixed, the hair protein is restored, the scales close, and the hair returns to its natural position.

Fixation must be given special attention: if it is done incorrectly, the curl will be fragile.

When perming, each hair experiences not only chemical, but also physical effects: pressure and tension. The diameter of the bobbins does not in any way affect the speed, but it completely depends on the degree of elasticity of the curls.

In addition, the degree of elasticity depends on:

It should be remembered that each subsequent perm will not be as beautiful and strong as the previous one. Chemical components destroy keratin, forming a new substance in the hair, the so-called meta-keratin, which reacts much weaker to chemicals. After some time, the strands may simply “refuse” to curl, and in this case, the woman will have to wait until they grow up.

There are many types of perms; they are divided both by the type of chemical composition used and by the method of curling. Every year more and more different chemical preparations for curling and new types of bobbins appear.

Root hair perm method

This method allows the hairstyle to look fuller and thicker, and also makes it easier their installation. The root method is especially recommended for women with weak curls or hair that has grown back after a perm, as well as for creating hairstyles with volume at the roots of the hair.

The root perm method involves curling not all hair, but its root parts. The ends of the strands remain untouched.

It is permissible to start this type of curling from any place on the head, you just need to keep in mind that if a woman has already used a perm, the bobbin must be wound, retreating two centimeters from the regrown edge. Let's say, if your hair has grown eight centimeters, the bobbin should be installed ten centimeters from the edge of the strands.

Twist the strands in the shape of a half-eight, holding the end of the strand in your left hand and supporting the bobbin with your right. Having completed the required number of revolutions (strictly towards the roots!), the bobbin is secured with an elastic band.

Having curled the curls, you need to proceed to the main stage: applying a chemical composition to the bobbins. The composition must be applied so that it does not fall on uncurled curls. Let the mixture sit for ten to twenty-five minutes.

Next stage: fixation. This procedure is performed by covering the upper part of the forehead with a napkin so that the fixative does not get into the eyes.

For one fixation you need fifty grams of three percent hydrogen peroxide. Apply the fixer with a sponge or applicator directly to the bobbins, foam it, and leave for about ten minutes.

After the foam settles, the bobbins need to be untwisted and the fixer reapplied for five minutes, then rinsed with warm water. Now you can begin the final work: drying, neutralizing, styling, etc.

Vertical curling - what is it?

Vertical perm appeared more than half a century ago, but still does not lose its relevance. Vertical bobbins allow you to create a hairstyle with light, bouncy and playful curls.

Applicable vertical curl regardless of the length of the hairstyle, but, of course, curls will look much more attractive on long hair.

The hair is twisted in the reverse order - from roots to ends, distributed along the entire length of the bobbin as evenly as possible.

The bobbins used are special, cone-shaped, with holes for pulling strands through. It is best to take wooden or polymer bobbins.

Vertical perm, performed in hairdressing salons, is divided into stages:

• • Hair washing, haircut if necessary.
  • Comb the strands, divide them into squares, starting from the back of the head. The diameter of each square should be equal to the diameter of the bobbin base.
  • Secure the hairstyle with clips.
  • Using a sponge, apply the chemical starting from the ends.
  • Before winding, pull the strands through the holes at the base of the bobbins.
  • Curl your hair starting from the back of your head.
  • Secure the strands with gauze tape soaked in a chemical composition. Wind the tape in the same direction as the hair.
  • Place a rubber clamp ring on each bobbin.
  • Moisten each strand generously with the chemical composition.
  • Steam hair treatment using a special apparatus.
  • Rinse hair.
  • Fixation.

After all the procedures, you get a whole head of large, beautiful curls.

Spiral hair chemistry

This method is performed using special modified bobbins. Strands of hair are twisted into a bundle and wound in a spiral onto a bobbin, placing each turn as close to each other as possible. It should be remembered that the direction of twisting the hair rope and winding the hair onto the bobbin must coincide.

Then all the stages characteristic of a perm are performed: securing the strands, applying the composition, fixing, etc.

Japanese technology...

Perm using a special lipid-protein complex (LC2) is also called Japanese perm. This type is especially recommended for women with problem hair. The curl is long-lasting, silky, special complex made of lipids and proteins gives the hair elasticity and shine. The curls are of medium hardness and are great for long curls.

When perming a Japanese hairstyle, a cap made of polyethylene is often used, which has holes around the entire perimeter. Hair strands are pulled into these holes using a special device. Then the chemical composition is applied. The scalp is protected from interaction with chemicals, so this technique is suitable for women who have problems with skin heads.

Wet hair chemicals

Wet chemistry allows you to create the effect of elastic, very small curls without the “fluffiness” that is so unpleasant for ladies. After wet chemicals, the strands look beautiful and well-groomed.

This method uses small curlers and chemicals. different classes. To style your hair, use varnish or foam with the effect wet hair. Lasts up to three months, but is not suitable for all women. For example, ladies with coarse hair may waste their money - it will straighten out very quickly. Women with oily hair are not advised to use wet chemicals: in this case, curls with a wet effect will look like unwashed ones.

Light chemistry or carving

Damages hair to a lesser extent than other methods. It is most often used to give hair volume at the very roots. In addition, light chemicals are used for curling curls and long-term styling.

The effect of light chemotherapy lasts approximately eight weeks. Carving is done exclusively in salons experienced craftsmen. When performing the procedure, curlers of different diameters are used.

Hair curling large curls

Today, large silky curls are extremely popular among women. You can control the elasticity of the curl by monitoring the exposure time to the chemical composition. To keep your curls soft, you just need to shorten the exposure time.

In order for large curls to be elastic, it is necessary to use special means for hair care that smooths out damage and unevenness.

The size of the curl depends on the thickness of the bobbin. The volume lasts up to eight weeks.

How to perm short, long, medium hair

Perm for long strands is carried out according to the following method:

• Separate thin rows, starting from the back of the head.
• Wind the strands in a spiral onto the bobbins, distributing the turns evenly along the entire length.
• The first row of bobbins should be on the back of the head; second row - at the temples and to the central part of the back of the head; the third is slightly higher than the second; the fourth row is at the top of the head.
• After screwing, standard operations are performed - applying the composition, rinsing, fixing.

Women with short hair should pay attention to the root method, which allows them to lift their hair. Perm on the ends looks very impressive short hair. An acid perm lasts on short hair for about six months; this look is especially suitable for women with oily hair.

Almost all types of perms are suitable for medium-length hair. You can use the Japanese technique, root, vertical, etc. The average length is essentially universal, which gives the hairdresser the opportunity to experiment.

How to restore hair after this procedure?

Obviously, chemicals are stressful for hair, so after it you need to follow several rules aimed at hair restoration:

• You should wash your hair no more than three times a week, because shampoo removes the protective fat layer from the hair along with dirt. After chem. curl protection is already weak, and frequent washing will lead to excessive dryness hair and even dandruff. It is better to use a mild baby shampoo. Wash your hair with water at a temperature of no more than thirty degrees, while doing a massage.
• It is better to cut the ends, this stimulates hair growth.
• It is imperative to use special masks and balms that restore strength and health to your hair.
• B vitamins should be taken internally.

We should not forget about folk remedies for hair restoration after perm. For example, to improve the nutrition of the scalp, you need to rub pepper tincture into it twice a week.

To strengthen your hair, apply a mask of burdock oil, yolk, onion juice and cognac, leaving for thirty minutes, then washing off.

An egg mask is considered an excellent way to restore curls after a perm. It is prepared from three eggs and three tablespoons of burdock oil. Apply the mask to your hair and cover with a cap. After about half an hour, wash off.

On this page you can see the types of curls in the photo, which illustrate the various options. All proposed types of hair curling in the photo are distinguished by their simplicity and accessibility at home. Almost all types of hair curls are discussed briefly and their pros and cons are suggested. From the article you can find out what types of hair curling there are, and why you should give preference to one method or another. What types of curls are dangerous and not recommended for use - this question also has an answer on this page.

Using curling, you can create bouncy curls or light waves and add additional volume to your hairstyle. To achieve a short-term effect, you can use curlers or hot tongs; permanent curling using chemicals will help make your hair curly for a long time.

What types of hair curls are there: braiding and curlers?

First, let's look at the simplest method and tell you about the types of hair curling by braiding. Dry clean hair with a towel and wait until it is half dry. Divide them into equal strands, comb each one carefully, simultaneously distributing a styling product (gel or mousse) along the entire length of the hair, and then braid it tightly. Secure the end with tape or curl it with curlers. Leave your hair braided until the morning. Then undo the braids and give the hair the desired shape using your fingers and a hairdryer with cold air. Fix the hairstyle with hairspray.

Every woman has tried curling her hair with curlers at least once in her life. This is one of the simplest and most common ways to create stylish styling, add volume to your hair and change your look. The answer to the question of what kind of hair curls exist depends only on the arsenal of curlers that a fashionista has in her arsenal.

If your hair is thin, you should not use large-diameter curlers for curling. The effect of small and medium-sized curlers will be more noticeable on such hair.

On a note

Thermal and electric curlers do not differ in principle from conventional ones, but they allow you to achieve the desired effect faster due to the additional thermal effect on the hair.

Hair, washed and conditioned, should be dried with a towel and wait until it is half dry. Then divide them into equal strands, comb each one carefully, simultaneously distributing a styling product (gel or mousse) along the entire length, and then wind each strand with curlers. After a few hours (to achieve the greatest effect, the curlers should be left overnight), remove them and carefully comb your hair, at the same time styling with your fingers. Fix the hairstyle with hairspray.

Curling using hot curling irons. Before curling your hair with a hot curling iron, you need to wash it with shampoo and conditioner, dry it without using a hair dryer and comb it carefully. Apply styling gel or wax with protective properties to them, distribute the product along the entire length of the strands using a thin comb.

You should curl strands 1-2 cm thick. Carefully wind each one onto a hot curling iron, starting from the ends of the hair, evenly distributing them over the entire surface of the curling iron at a slight angle. Hold for 20 seconds, then carefully remove the strand from the curling iron, if possible without unwinding it.

After curling, style your hair in the desired way and secure the hairstyle with hairspray.

You can style the curls only after they have completely cooled, otherwise the durability of the curl will be significantly reduced.

Hot tongs can also be used to add volume to short strands. To do this, each one must be lifted at the roots with a thin wooden comb, screwed onto a curling iron, held for 5-10 seconds, then removed from it.

Finally shape the hairstyle with your hands, highlighting and fixing the strands with gel or styling wax.

What types of hair perm are there (with photo)

Types of hair perm are deservedly popular. After all, depending on the type of hair perm, the result can last for several months. Next, you can read about what types of perm there are and what their proposed methods are best to choose.

It is also suggested to look at the types of hair perm in the photo, which illustrate the result:

Permanent wave. Permanent hair perm is carried out using chemicals, the composition of which determines how effective and gentle the procedure will be.

Acid perm. The acidic base of the curling composition ensures its durability, but is quite damaging to the hair.

Alkaline perm. The alkaline base has a gentler effect on the hair, but is less durable (lasts no more than 3 months) and is not suitable for all hair types.

Neutral curl. A neutral base is suitable for any hair type and does not harm the hair, but does not provide a long-term effect.

Depending on the additional devices used to create curls, the following types of permanent perm are distinguished:

Curling with horizontal curlers. Using curlers of various lengths and diameters for perm, you can create the effect of naturally curly hair.

Spiral curl. The result of this curling is small elastic curls. Best suited for long hair.

Curling by braiding. With this method of curling, the hair is braided into thin, tight braids, and their ends are wound on small-diameter curlers, after which the hair is treated with a chemical composition.

To avoid contact of the chemical composition with the scalp, some salons perform so-called safe perms. During this procedure, a plastic cap is put on the head, the strands are pulled out through the holes in it, and only after that they are treated with a special chemical composition for curling.

Curling with hairpins. As a result of this curling, chaotically curly hair is obtained, forming a voluminous hairstyle. The effect is achieved by winding thin strands onto non-metallic hairpins.

Curl at the roots. It is used to give hair volume from the roots, as well as in cases where hair that was previously permed has grown back. After perm, hair becomes more sensitive to various negative factors, so it requires special care. So, to wash them, you should choose a special shampoo for hair with permanent curling or a mild detergent for weakened and damaged hair. After each hair wash, you must use a nourishing balm, and apply restorative masks at least 2 times a week. Additional attention should be paid to the prevention of split ends.

Since the beginning of time, people have been interested in the composition, structure and interaction of everything that surrounds them. This knowledge is combined into a single science - chemistry. In the article we will consider what it is, sections of chemistry and the need to study it.

and why study it?

Chemistry is one of several branches of natural science, the science of substances. She is studying:

• structure and composition of substances;
• properties of elements of the surrounding world;
• transformations of substances that depend on their properties;
• changes in the composition of a substance during a chemical reaction;
• laws and patterns of changes in substances.

Chemistry considers all elements from the point of view of atomic and molecular composition. It is closely related to biology and physics. There are also many areas of science that are borderline, that is, they are studied, for example, by both chemistry and physics. These include: biochemistry, quantum chemistry, chemical physics, geochemistry, physical chemistry and others.

The main branches of chemistry in the literature are:

1. Organic chemistry.
2. Inorganic chemistry.
3. Biochemistry.
4. Physical chemistry.
5. Analytical chemistry.

Organic chemistry

Chemistry can be classified based on the substances being studied into:

• inorganic;
• organic.

We will consider the first area of ​​study in the next paragraph. Why was organic chemistry separated into a separate section? Because she studies carbon compounds and the substances that contain them. Today, about 8 million such compounds are known.

Carbon can combine with most elements, but most often interacts with:

• oxygen;
• carbon;
• nitrogen;
• gray;
• manganese;
• potassium

The element is also distinguished by its ability to form long chains. Such connections provide a variety of organic compounds that are important for the existence of a living organism.

Objectives and methods followed by the subject of organic chemistry:

• isolation of individual individual and special substances from plant and living organisms, as well as from fossil raw materials.
• purification and synthesis;
• determination of the structure of matter in nature;
• study of the course of a chemical reaction, its mechanisms, features, and results;
• determination of relationships and dependencies between the structure of organic matter and its properties.

Sections of organic chemistry include:

Inorganic chemistry

The branch of inorganic chemistry deals with the study of the composition, structure and interactions of all substances that do not contain carbon. Today there are more than 400 thousand inorganic substances. Thanks to this particular branch of science, the creation of materials for modern technology is ensured.

Research and study of substances in inorganic chemistry is based on the periodic law, as well as the periodic system of D. I. Mendeleev. Science studies:

• simple substances (metals and non-metals);
• complex substances (oxides, salts, acids, nitrites, hydrides and others).

Objectives of science:

Physical chemistry

Physical chemistry is the most extensive branch of chemistry. She studies the general laws and transformations of substances using physics methods. For this purpose, theoretical and experimental ones are used.

Physical chemistry includes knowledge about:

• structure of molecules;
• chemical thermodynamics;
• chemical kinetics;
• catalysis.

The sections of physical chemistry are as follows:

Analytical chemistry

Analytical chemistry is a branch of chemistry that develops the theoretical basis of chemical analysis. Science is concerned with developing methods for identifying, separating, detecting and determining chemical compounds and establishing the chemical composition of materials.

Analytical chemistry can be classified depending on the problems being solved into:

• Qualitative analysis- determines what substances are in the sample, their form and essence.
• Quantitative Analysis- determines the content (concentration) of components in the test sample.

If you need to analyze an unknown sample, then qualitative analysis is used first, and then quantitative. They are carried out using chemical, instrumental and biological methods.

Biochemistry

Biochemistry is a branch of chemistry that studies the chemical composition of living cells and organisms, as well as their basic life functions. Science is quite young and is at the intersection of biology and chemistry.

Biochemistry studies the following compounds:

• carbohydrates;
• lipids;
• proteins;
• nucleic acids.

Sections of biochemistry:

Chemical Technology

Chemical technology is a branch of chemistry that studies economical and environmentally sound methods of processing natural materials for consumption and use in production.

Science is divided into:

• Organic chemical technology, which processes fossil fuels and produces synthetic polymers, medicines and other substances.
• Inorganic chemical technology, which processes mineral raw materials (except metal ore), produces acids, mineral fertilizers and alkalis.

There are many processes going on (periodic or continuous). They are divided into main groups:

The occurrence of certain chemical processes and the properties of individual substances arouse unusual interest among people.

Here are some of them:

1. Gallium. This is an interesting material that tends to melt at room temperature. Looks like aluminum. If a gallium spoon is placed in a liquid at a temperature above 28 degrees Celsius, it will melt and lose its shape.
2. Molybdenum. This material was discovered during the First World War. Studies of its properties have shown the high strength of the substance. Later, the legendary Big Bertha cannon was made from it. Its barrel did not deform from overheating when firing, which simplified the use of the gun.
3. Water. It is known that water in its pure form, H 2 O, does not occur in nature. Thanks to its properties, it absorbs everything that comes its way. Therefore, a truly pure liquid can only be obtained in the laboratory.
4. Another special property of water is also known - its reaction to changes in the surrounding world. Studies have shown that water from the same source changes its structure under different influences (magnetic, with music on, near people).
5. Mercaptan. It is a combination of sweet, bitter and sour tastes that was discovered after studying grapefruit. It has been established that a person notices this taste at a concentration of 0.02 ng/l. That is, it is enough to add 2 mg of mercaptan for a volume of water of 100 thousand tons.

We can say that chemistry is an integral part of the scientific knowledge of mankind. She is interesting and multifaceted. It is thanks to chemistry that people have the opportunity to use many objects of the modern world around them.

Beautiful curls of any shape and size that last for several months are the result of a procedure known as perm. It has been in fashion for several decades in a row. During this time, the quality of the compositions has changed, new types of curlers and methods of curling strands have been added. And yet, despite serious innovations, chemicals are still considered harmful to hair. We will not convince you otherwise, but instead we will tell you how to protect your curls from damage and restore their structure after curling. Find out how to safely carry out the procedure at home and whether it is possible to get rid of curls without disastrous consequences if the experiment with hair was unsuccessful.

Description of the procedure

The main feature of perm is changing the hair structure using special solutions. The strands need to be wound on curlers of the chosen shape and diameter, treated with the composition, and after a while, washed off. In 10–30 minutes, the active components penetrate into the curls, providing a lasting curling result.

Chemical solutions are produced by many cosmetic companies. You need to choose the right product taking into account the type and condition of your hair. The corresponding marks are always on the packages or bottles.

By the way. The first experiments with chemical hair styling date back to the beginning of the 20th century. These were tedious procedures that lasted 5–10 hours. Cold way, without the use of electrical appliances, appeared a little later. It became the basis of modern chemistry.

Kinds

There are several classifications of perm, in which the main criterion is:

• type of curlers - boomerangs, bobbins or others;
• method of winding strands - vertical, horizontal, circular, combined;
• sequence of actions (you can first treat your hair with a solution and then curl it with curlers);
• variety chemical preparation. Compositions can be acidic, alkaline, neutral and others. All of them have clear indications for use.

An alkaline product may not form curls on thick, coarse hair, while an acidic product can severely damage soft, pliable strands. To avoid becoming the main character in a story about chemistry gone wrong, Before the procedure, you should consult with an experienced hairdresser.

We also organized a kind of educational program and described in detail the features different types solutions, including examples of products from popular brands. With these recommendations, you can easily select a safe composition for your hair.

Price

The price of a classic perm in a salon is from 2 thousand rubles. In a small city you can find it cheaper, but in a metropolis you will have to pay even more. The cost is also influenced by the chosen composition and hair length. If you buy chemical preparations for independent experiments, you can spend 1 thousand rubles.

For some solutions from well-known cosmetic companies you will have to pay a little more, up to 2 thousand rubles. There are ready-made kits with everything you need at prices ranging from 300 to 1200 rubles, or individual bottles with activators and fixatives, each of which costs about 200–900 rubles.

Advantages and disadvantages

The main advantages of perm:

• changes her hairstyle, and with it her entire image;
• lasts for a long time;
• suitable for hair of any length;
• has many variations;
• reduces daily styling time - with minimal effort, the hairstyle looks great.

Disadvantages of the procedure:

• has a damaging effect on hair. Depending on the composition, it may be more or less obvious, but the structure of the curls still suffers;
• may dry out strands and slightly change their color;
• has contraindications and restrictions;
• requires special care aimed at hair restoration;
• not recommended for frequent repetition. You need to give your curls a chance to rest.

Contraindications

The main list of prohibitions and restrictions concerns the following situations:

1. Modified hormonal background. You should not get a perm during pregnancy, lactation, during menstruation or menopause. Disputes are still ongoing about whether active reagents harm an expectant or nursing mother and her baby. If that doesn't stop you, here's another good reason: due to hormonal changes, curls may not form properly.
2. Taking antibiotics or other strong drugs (including hormones).
3. Allergy to the components of the solution. This factor must be excluded before the procedure.
4. Abrasions, wounds, cracks on the scalp, as well as itching, flaking, and dandruff.
5. Severe hair loss, brittle hair. It doesn’t matter what it’s connected with: vitamin deficiency, depression, or a course of oncology procedures. With chemicals you will weaken the strands even more.
6. Stressful conditions.
7. Exacerbation of chronic ailments.
8. Acute infectious diseases complicated by elevated body temperature.
9. Hair coloring, after which less than 2–3 weeks have passed.
10. Some external factors: visiting the hairdresser on an empty stomach, cold indoors also negatively affect the quality of curls.

Types of curlers and methods of curling

If the perm composition affects how well the curls come out, then curlers determine the appearance of the hairstyle as a whole.

Much depends on the thickness of the strands and the method of winding. Lush curls that look very natural are the result of circular curling of hair on curlers. If you need to get voluminous curls, a horizontal option for placing rollers on your head is suitable. It is often used at home - for beginners it is simpler and more understandable than other methods.

To create beautiful flowing curls you will have to master the vertical method. It is often combined with horizontal, but such installation should only be entrusted to an experienced professional. This option is one of the most suitable for long hair.

If you want to become the owner of a voluminous hairstyle, buy large-diameter curling irons for perming.

Choose boomerangs or cone products. Olivia Garden curlers can provide beautiful, almost natural waves. The chemistry using these rollers is called American. Large curls will decorate hair of almost any length, so we have collected tips and tricks for you on how to create such curls at home. Plastic curlers are considered the most suitable for any perm.

They are convenient to use and easy to wash off traces of the drug. Using plastic bobbins (sticks) of different diameters, you can simulate beautiful vertical curls from the roots. The installation may take a lot of time, but the result is worth it. When deciding on the size of the products, consider the condition of your hair.

Find out what else should determine the choice of bobbins for vertical perm. The second type is intended for spiral chemistry. The process of winding on such bobbins requires a lot of patience and attention. Doing it on your own is quite difficult. You should only do this type of perm if you have enlisted the help of your mother, sister or friend, and also watched a training video beforehand.

For the bravest girls, we have prepared a complete set of information on performing spiral chemistry at home.

The same bobbins will be useful for women who want to perm their hair with the effect of wet hair. In addition to them, you can use hair curlers, American or Japanese sticks. Any of these curlers will help achieve the effect of always-wet hair.

Properly selected bobbins, the optimal composition for your hair type and step-by-step instructions for the procedure - all this will be the key to a good result. We will explain in detail how to perform wet chemicals on your own hair without compromising the health of the strands and the quality of the curls.

By the way. Pay attention to the original curlers for perming hair: pins, wave-shaped plates, coils with clamps and others.

Can it be done on thin, colored strands?

Dyeing, supplemented with perm, is a serious test for hair. However, many girls successfully combine a new color of strands and long-term styling of curls. The main recommendation in this case is to maintain an interval between procedures: it is advisable that at least 2–3 weeks pass. If your hair has been bleached several times in a row, it is better to avoid chemicals.

As a result of constant dyeing, hair partially loses its elasticity and becomes more vulnerable, so additional exposure to aggressive drugs can further undermine its health. We will reveal the main secrets of successful perm of colored strands and explain what compositions can be used in this case.

If your hair is naturally strong, strong and has not been dyed frequently, this is a significant bonus when undergoing chemical treatments.

Quite often, girls choose perms to add extra volume to their hair. In this case, you don’t need to use aggressive drugs along the entire length of the curls. An alternative to full-fledged chemistry is root treatment. It makes thin, sparse hair look fuller, corrects overgrown strands that have been artificially curled, and also creates volume on naturally curly hair. Like any other type of perm, root styling has its own nuances, which we will discuss in detail in the review material with photos, videos and step-by-step instructions for the procedure.

Features related to the length of curls

Curls will become a worthy decoration of your appearance if you choose the right size and shape. Large curls are undesirable on thin, sparse hair - it is better to choose small ones. A round face should be framed with curls, the diameter of which gradually decreases from roots to tips, and a square or rectangular face with voluminous horizontal curls. The length of the strands is important when choosing the size and type of curlers.

Advice. A perm done on graduated hair or a cascade haircut looks good.

Long

On hair that goes down below the middle of the back, curls of any shape and size are appropriate. Long hair will show all the beauty of a skillfully done perm. Indeed, in this case it will be especially labor-intensive. For the first time, you can perform chemistry only on the ends or from the middle of the curls. If you don’t like the result, you can simply cut off the curls. We will tell you in detail about other nuances of performing the procedure on long hair and will help you decide whether it is worth experimenting at home.

Average

Such strands are also good for various types of curlers and curling methods. Perm only in the root zone or at the ends, with boomerangs or bobbins, horizontal, vertical, combined and other methods - medium-length hair does not limit your imagination and possibilities. At the same time, remember that some types of chemicals can visually shorten your hair: the curls curl tightly and become elastic, like a spring. Our tips will help you avoid all sorts of surprises when getting a perm.

Short

Despite the short length, curling such hair with your own hands is quite difficult. Depending on the haircut and the thickness of the strands, the method of curling the curlers can be checkerboard, rectangular, or vertical.

The shape and diameter of the curlers, as well as the quality of the solution, are also important. We will tell you about all the nuances of the procedure for short hair, and also explain how to care for your hair after chemical treatment performed in the salon or at home.

Procedure at home Preparation of strands for perm begins several weeks before the procedure. Pay special attention to caring for your curls: pamper your hair nourishing masks

, give her a break from curling irons, hair dryers, and ironing. Update your haircut, if necessary, color your hair in advance. Read reviews about performing chemistry at home, select the composition, curlers, and all other related tools and materials.

So that you don’t forget anything, we have prepared a detailed list of what you will need for a perm, and have carefully outlined all the stages of the procedure. Step-by-step instructions with tips and life hacks will be a good help on the path to transformation.

Effect duration and correction Using a perm will not make your hair curly forever. Despite the rapid development of modern technologies, such a method has not yet been invented. On average, the effect of chemistry lasts from 2 to 6 months, sometimes up to 9.

The duration of the result is influenced by the selected composition (acidic or alkaline), the type and structure of the strands (thin, thick, sparse, hard), their length (the shorter the curls, the better the curls hold), the size of the curl (volumetric ones unwind faster), the individual characteristics of each hair. With chemical styling, unlike bio-curling, the boundary between regrown and curled hair is more noticeable. That's why After a few weeks, the hairstyle may require correction.

In this case, it is better to do a root perm. It is recommended to repeat the chemical treatment along the entire length of the curls no more than 1-2 times a year.

Installation and further care The first few days, curled hair needs rest.

Gels, foams, sprays and other products will give your curls a beautiful, shaped look. We have collected in one review a description of popular products and recommendations on how to use them to create voluminous, classic or wet styling.

Taking care of the attractive appearance of your hair should be accompanied by proper care after them. Restoration and nutrition of the structure of curls is the main thing that needs to be paid attention to. If the solution dries out the strands, add moisturizers to your main cosmetics.

Preparations intended for damaged, weakened hair are very useful. We'll tell you how to care for your hair after chemical styling and explain why you'll most likely need to change your comb.

Not every chemical treatment brings excitement about a new hairstyle. There are times when, for some reason, the curls do not curl as you expected. Sometimes the procedure provokes increased hair loss, fragility of strands, or causes an allergic reaction on the skin, tightening and drying it. A less dramatic version of events is also possible - you didn’t like the styling at all or got tired of it. In all these situations, advice on how to get rid of chemicals from professional and folk ways

outlined in our article. No matter how much they talk about the dangers of perm for hair, this does not stop girls who dream of curls. If you choose a high-quality composition, follow the procedure according to all the rules, and then provide your curls with decent care, there is every chance of maintaining the health of your hair. Just don't forget about contraindications.