• Domestic science and medicine in the 19th - early 20th centuries Chemistry of the 19th century in medicine
• What are peptides? Types and types of peptides. All about peptides and anti-aging cosmetics with peptides Additional peptides are not formed
• Toxic effect on humans of hazardous chemicals
• Radioautography Method of autoradiography in cytology
• Identification of bacteria by antigenic structure
• Organic matter in wastewater What are organic compounds in water
• Hydrogen index (pH factor)
• What is the pH of water and why is it important to know it?
• Redox potential Redox systems
• Reversible redox system Reversible redox systems

Matter is what physical bodies are made of.

There are a lot of substances, and they all have different properties. For example, sugar and table salt are white crystalline solids, but they differ in taste and water solubility; water and acetone are colorless liquids, but water is odorless, and acetone, which you know as a good solvent for varnishes and paints, has a characteristic odor; oxygen and hydrogen are colorless gases, but hydrogen is 16 times lighter than oxygen.

One of the tasks of chemistry is to learn to distinguish substances by their physical and chemical properties, and sometimes by their physiological action. For example, a well-known substance - table salt - can be characterized as follows: a white solid, salty taste, brittle, soluble in water, melting point 801 ° C, boiling point 1465 ° C.

Another task of chemistry is to obtain various substances, many of which are not found in nature: plastics, some mineral fertilizers (superphosphate, ammonium nitrate), plant protection products, drugs (aspirin, streptocide), detergents, etc. These substances are obtained by various chemical transformations.

Connection of chemistry with other sciences

Chemistry is one of the branches of natural science, it is closely connected both with other sciences and with all branches of the national economy.

The transformation of one substance into another is accompanied by various physical phenomena, such as the release or absorption of heat. Therefore, chemists need to know physics.

The basis of the existence of wildlife is metabolism. A biologist who is ignorant of the laws of chemistry will not be able to understand and explain this process.

Chemical knowledge is also necessary for a geologist. Using them, he will successfully conduct a search for minerals. A doctor, pharmacist, cosmetologist, metallurgist, culinary specialist, without the appropriate chemical training, will not reach the heights of skill.

Chemistry is an exact science. Before carrying out a chemical experiment and after its completion, a chemist performs the necessary calculations. Their results make it possible to draw correct conclusions. Therefore, the activity of a chemist is impossible without knowledge of mathematics.

The contact of chemistry with other sciences gives rise to specific areas of their mutual penetration. Thus, the areas of transition between chemistry and physics are represented by physical chemistry and chemical physics. Between chemistry and biology, chemistry and geology, special border areas arose - geochemistry, biochemistry, biogeochemistry, molecular biology. The most important laws of chemistry are formulated in mathematical language, and theoretical chemistry cannot develop without mathematics. Chemistry has exerted and is exerting an influence on the development of philosophy, and has itself experienced and is experiencing its influence.

The environment is becoming increasingly polluted due to the introduction of excessive amounts of fertilizers into the soil, the release of vehicle exhaust gases into the air, harmful substances from various industries into water bodies, as well as household waste. All this leads to the destruction of plants, the death of animals, and the deterioration of human health. A serious threat to all living things is chemical weapons - special, extremely toxic substances. Destroying stockpiles of such weapons requires considerable effort, money and time.

The relationship between man and nature is studied by the young natural science of ecology. The problems of environmental protection from pollution are constantly in the field of view of environmental scientists. The preservation of nature for future generations depends on the careful attitude of each of us towards it, on the level of our culture and chemical knowledge.

The emergence of chemistry as a science, the main stages of its development.

The origin of chemistry is associated with the development of chemical processes and crafts, such as metal smelting, brewing, leather tanning and dyeing, which provided practical information about the behavior of substances. The path of its development is long, instructive and interesting.

The main stages in the history of chemical science include:

1st stage. From ancient times to the end of the 18th century. Alchemical period, Works by R. Boyle.

2nd stage. Chemistry as a science. Works by Lomonosov, Dalton, Lavoisier.

3rd stage. XIX and. Atomic-molecular theory, the formation of the fundamental theoretical foundations of chemistry. Discovery by Mendeleev D.I. Periodic Law of 1809.

4th stage. Modern period of successful revival of chemistry. Scientific and practical research in the field of chemistry.

Chemistry plays a huge role in the life of modern society. Chemistry invades all areas of science, technology, production, agriculture, everyday life, introducing revolutionary changes in the usual processes and methods, saving labor, money, time and materials, increasing people's wealth. Now the words of the great Russian scientist M. V. Lomonosov are especially confirmed: "Chemistry spreads its hands wide in human affairs."

In the modern world, there are thousands of different sciences, educational disciplines, sections and other structural links. However, a special place among all is occupied by those that relate directly to a person and everything that surrounds him. This is the system of natural sciences. Of course, all other disciplines are also important. But it is this group that has the most ancient origin, and therefore of particular importance in people's lives.

What is natural sciences?

The answer to this question is simple. These are disciplines that study a person, his health, as well as the entire environment: soil, in general, space, nature, substances that make up all living and inanimate bodies, their transformations.

The study of natural sciences has been interesting to people since antiquity. How to get rid of the disease, what the body consists of from the inside, and what they are, as well as millions of similar questions - this is what interested humanity from the very beginning of its occurrence. The disciplines under consideration give answers to them.

Therefore, to the question of what the natural sciences are, the answer is unequivocal. These are disciplines that study nature and all living things.

Classification

There are several main groups that relate to the natural sciences:

1. Chemical (analytical, organic, inorganic, quantum, organoelement compounds).
2. Biological (anatomy, physiology, botany, zoology, genetics).
3. chemistry, physical and mathematical sciences).
4. Earth sciences (astronomy, astrophysics, cosmology, astrochemistry,
5. Earth shell sciences (hydrology, meteorology, mineralogy, paleontology, physical geography, geology).

Only the basic natural sciences are represented here. However, it should be understood that each of them has its own subsections, branches, subsidiary and child disciplines. And if you combine all of them into a single whole, then you can get a whole natural complex of sciences, numbering in hundreds of units.

At the same time, it can be divided into three large groups of disciplines:

• applied;
• descriptive;
• accurate.

Interaction of disciplines among themselves

Of course, no discipline can exist in isolation from others. All of them are in close harmonious interaction with each other, forming a single complex. So, for example, knowledge of biology would be impossible without the use of technical means designed on the basis of physics.

At the same time, transformations inside living beings cannot be studied without knowledge of chemistry, because each organism is a whole factory of reactions occurring at an enormous speed.

The relationship of the natural sciences has always been traced. Historically, the development of one of them entailed intensive growth and accumulation of knowledge in the other. As soon as new lands began to be developed, islands, land areas were discovered, both zoology and botany immediately developed. After all, new habitats were inhabited (albeit not all) by previously unknown representatives of the human race. Thus, geography and biology were closely linked together.

If we talk about astronomy and related disciplines, it is impossible not to note the fact that they developed thanks to scientific discoveries in the field of physics and chemistry. The design of the telescope largely determined the success in this area.

There are many such examples. All of them illustrate the close relationship between all natural disciplines that make up one huge group. Below we consider the methods of natural sciences.

Research methods

Before dwelling on the research methods used by the sciences in question, it is necessary to identify the objects of their study. They are:

• human;
• life;
• Universe;
• matter;
• Earth.

Each of these objects has its own characteristics, and for their study it is necessary to select one or another method. Among these, as a rule, the following are distinguished:

1. Observation is one of the simplest, most effective and ancient ways to know the world.
2. Experiment is the basis of the chemical sciences, most of the biological and physical disciplines. Allows you to get the result and on it to draw a conclusion about
3. Comparison - this method is based on the use of historically accumulated knowledge on a particular issue and comparing them with the results obtained. Based on the analysis, a conclusion is made about the innovation, quality and other characteristics of the object.
4. Analysis. This method may include mathematical modeling, systematics, generalization, effectiveness. Most often it is final after a number of other studies.
5. Measurement - used to assess the parameters of specific objects of living and inanimate nature.

There are also the latest, modern research methods that are used in physics, chemistry, medicine, biochemistry and genetic engineering, genetics and other important sciences. It:

• electron and laser microscopy;
• centrifugation;
• biochemical analysis;
• x-ray structural analysis;
• spectrometry;
• chromatography and others.

Of course, this is not a complete list. There are many different devices for working in every field of scientific knowledge. Everything requires an individual approach, which means that a set of methods is formed, equipment and equipment are selected.

Modern problems of natural science

The main problems of the natural sciences at the present stage of development are the search for new information, the accumulation of a theoretical knowledge base in a more in-depth, rich format. Until the beginning of the 20th century, the main problem of the disciplines under consideration was opposition to the humanities.

However, today this obstacle is no longer relevant, since humanity has realized the importance of interdisciplinary integration in mastering knowledge about man, nature, space and other things.

Now the disciplines of the natural science cycle face a different task: how to preserve nature and protect it from the impact of man himself and his economic activity? And here are the most pressing issues:

• acid rain;
• Greenhouse effect;
• destruction of the ozone layer;
• extinction of plant and animal species;
• air pollution and others.

Biology

In most cases, in response to the question "What is the natural sciences?" One word comes to mind: biology. This is the opinion of most people who are not connected with science. And this is absolutely correct opinion. After all, what, if not biology, directly and very closely links nature and man?

All disciplines that make up this science are aimed at studying living systems, their interaction with each other and with the environment. Therefore, it is quite normal that biology is considered the founder of the natural sciences.

In addition, it is also one of the oldest. After all, to himself, his body, the surrounding plants and animals was born together with man. Genetics, medicine, botany, zoology, and anatomy are closely related to the same discipline. All these branches make up biology as a whole. They also give us a complete picture of nature, and of man, and of all living systems and organisms.

Chemistry and physics

These fundamental sciences in the development of knowledge about bodies, substances and natural phenomena are no less ancient than biology. They also developed along with the development of man, his formation in the social environment. The main tasks of these sciences are the study of all bodies of inanimate and living nature from the point of view of the processes occurring in them, their connection with the environment.

So, physics considers natural phenomena, mechanisms and causes of their occurrence. Chemistry is based on the knowledge of substances and their mutual transformations into each other.

That's what the natural sciences are.

Earth sciences

And finally, we list the disciplines that allow you to learn more about our home, whose name is Earth. These include:

• geology;
• meteorology;
• climatology;
• geodesy;
• hydrochemistry;
• cartography;
• mineralogy;
• seismology;
• soil science;
• paleontology;
• tectonics and others.

In total there are about 35 different disciplines. Together they study our planet, its structure, properties and features, which is so necessary for the life of people and the development of the economy.

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Chemistry today

The birth of modern chemistry

Periodic Law

Features of modern chemistry

Conclusion

Chemistry today

"Chemistry stretches its hands wide in human affairs," - this catch phrase of Mikhail Lomonosov is especially relevant at the present time. Chemistry today is food and medicine, fuel and clothing, fertilizers and paints, analysis and synthesis, organization of production and quality control of its products, preparation of drinking water and disposal of wastewater, environmental monitoring and the creation of a safe human environment. "To master such a volume of knowledge is impossible!" exclaim the pessimist. "Nothing is impossible for a person who is passionate about his work," we answer. And if you decide to connect your fate with chemistry, we are waiting for you at our faculty. Here you will receive a fundamental university education, which will allow you not only to easily adapt to any workplace, but also to become a professional in your field.

Along with the traditional areas of application of the forces of chemists, chemical expertise is becoming increasingly important in the life of society. Indeed, at present, the number and variety of objects of expertise has noticeably increased: water, air, soil, food and manufactured goods, medicines and waste from various enterprises, and much more. Establishing the type of product, the fact and method of its falsification, monitoring the cleanliness of the environment, forensic examination - this is not a complete list of what an expert chemist should be able to do. The results obtained by specialist experts are a powerful source of search, diagnostic and evidence information, which contributes to the establishment of objective truth in the investigation of emergencies, the implementation of eco-analytical, sanitary-epidemiological and customs control. Specialists of this profile are needed by the internal affairs bodies and the FSB, the Ministry of Justice, the Ministry of Health, the Ministry of Emergency Situations, the customs service, and departments with environmental functions. Meanwhile, specialists of this kind in our country are practically not trained. Therefore, the Faculty of Chemistry of our university begins training specialists in the field of chemical expertise.

Every year, 50 first-year students begin their student life at our faculty, and in total about 250 students study at the faculty. In the junior years, students study, in addition to chemical disciplines, higher mathematics, computer science, physics, socio-economic disciplines, and a foreign language.

After the 3rd year, students voluntarily choose a department where they will receive the appropriate specialization. The faculty has three departments. The Department of Analytical Chemistry and Chemistry of Petroleum, abbreviated AChN, (Head of the Department - Professor V.I. Vershinin) deals with the problems of environmental protection, helps some enterprises of the petrochemical complex to solve production problems. It is the department of the Academy of Chemical Sciences, the only one in the city, that begins the training of chemists in the field of chemical expertise. The department has postgraduate studies in the specialties "analytical chemistry" and "methods of teaching chemistry".

The Department of Inorganic Chemistry is headed by Professor V.F. Borbat. Here you will be introduced to the problems of protecting metals from corrosion, treating heavy metals from wastewater, teaching various electrochemical methods of analysis, and much more. As a result, you will receive a specialization in electrochemistry. In addition, the department begins training specialists in the field of ecology and environmental protection, which is so important for our city. Students who have shown a penchant for scientific work can continue it at the department by enrolling in graduate school in the specialties "physical chemistry" and "electrochemistry".

At the Department of Organic Chemistry, headed by Professor R.S. Sagitullin, lead the synthesis of new organic compounds, develop fundamentally new methods for obtaining drugs, dyes, antioxidants, etc. Students at this department receive a specialization in "organic chemistry". And just like in the other two departments, there is a postgraduate study in the specialty "organic chemistry".

In addition to the above specializations, students can optionally receive one more, additional specialization - "Methods of Teaching Chemistry". This specialization will be especially useful for those students who, after graduation, decide to engage in teaching work in schools, technical schools, and universities.

The theoretical knowledge gained by students in lectures is consolidated in educational laboratories. The faculty has sufficiently large teaching areas, a good fleet of modern devices, and has its own computer class. The finale of education at the faculty is a thesis.

The versatility of the training of our specialists allows them to quickly master any workplace. You will meet graduates of the Faculty of Chemistry at industrial enterprises of the city, in certification laboratories, SES, environmental control, in universities, technical schools, and schools.

We hope to meet you among the applicants of our faculty. And if the time "X" has not yet come for you, or you have not yet decided on the choice of a profession, come to us at the Chemistry School, which operates on the basis of the faculty for students of grades 10-11. Here, under the guidance of experienced teachers, you will get a real opportunity to expand and deepen your knowledge of chemistry, get acquainted with the basics of analysis and synthesis, and perform scientific work on modern equipment.

Modern economic conditions are such that enterprises, in order to withstand competition, must constantly improve their technologies and forms of product quality control, and for this they simply need highly qualified chemists. At the same time, the enterprise should not pollute the environment, because otherwise it will have to pay huge fines, so it’s better to have good analytical chemists on staff who would monitor the content of harmful substances and control their emissions. So there will always be a demand for specialists with a university degree in chemistry. And gradually the air in our city will become cleaner, and the water will be lighter, and the bread will taste better.

The birth of modern chemistry

The ideas of ancient Greek natural philosophers remained the main ideological sources of natural science until the 18th century. Until the beginning of the Renaissance, science was dominated by the ideas of Aristotle. In the future, the influence of atomistic views, first expressed by Leucippus and Democritus, began to grow. Alchemical works relied mainly on the natural philosophical views of Plato and Aristotle. Most of the experimenters of that period were frank charlatans who tried to obtain either gold or the philosopher's stone with the help of primitive chemical reactions - a substance that gives immortality. However, there were real scientists who tried to systematize knowledge. Among them are Avicenna, Paracelsus, Roger Bacon, etc. Some chemists believe that alchemy is a waste of time. However, this is not so: in the process of searching for gold, many chemical compounds were discovered and their properties were studied. Thanks to this knowledge, the first serious chemical theory, the theory of phlogiston, was created at the end of the 17th century.

The phlogiston theory and the Lavoisier system

The creator of the phlogiston theory is Georg Stahl. He believed that phlogiston is contained in all combustible and oxidizable substances. Combustion or oxidation was considered by him as a process in which the body loses phlogiston. Air plays a particularly important role in this. It is necessary for oxidation in order to “absorb” phlogiston into itself. From the air, phlogiston enters the leaves of plants and their wood, from which, when restored, it is again released and returned to the body. Thus, for the first time, a theory describing the combustion processes was formulated. Its features and novelty consisted in the fact that the processes of oxidation and reduction were simultaneously considered in interconnection. The phlogiston theory developed Becher's ideas and atomistic ideas. It made it possible to explain the course of various processes in handicraft chemistry and, first of all, in metallurgy, and had a tremendous influence on the development of chemical crafts and the improvement of the methods of "experimental art" in chemistry. The theory of phlogiston also contributed to the development of the doctrine of the elements. Adherents of the phlogiston theory called metal oxides elements, considering them as metals devoid of phlogiston. Metals, on the other hand, were considered compounds of elements (metal oxides) with phlogiston. All that was required was to put all the provisions of this theory “upside down”. Which was done later. To explain that the mass of oxides is greater than the mass of metals, Stahl suggested (or rather claimed) that phlogiston has a negative weight, i.e. phlogiston, having connected with the element, “pulls” it up. Despite the one-sided, only qualitative characterization of the processes occurring during combustion, the theory of phlogiston was of great importance for explaining and systematizing precisely these transformations. The incorrectness of the phlogiston theory was pointed out by Mikhail Ivanovich Lomonosov. However, Antoine Laurent Lavoisier was able to experimentally prove this. Lavoisier noticed that during the combustion of phosphorus and sulfur, as well as during the calcination of metals, an increase in the weight of the substance occurs. It would seem natural to do this: an increase in the weight of the combusted substance occurs during all combustion processes. However, this conclusion was so contrary to the provisions of the theory of phlogiston that remarkable courage was needed to express it at least in the form of a hypothesis. Lavoisier decided to test the hypotheses put forward earlier by Boyle, Ray, Mayow, and Lomonosov about the role of air in combustion processes. He was interested in whether the amount of air increases if an oxidized body is reduced in it and additional air is released due to this. Lavoisier was able to prove that the amount of air actually increases. Lavoisier called this discovery the most interesting since the work of Stahl. Therefore, in November 1772, he sent a special message to the Paris Academy of Sciences about his results. At the next stage of research, Lavoisier thought to find out what is the nature of the “air” that combines with combustible bodies during their oxidation. However, all attempts to establish the nature of this "air" in 1772-1773. Ended in vain. The fact is that Lavoisier, like Stahl, restored “metal lime” by direct contact with “coal-like matter” and also received carbon dioxide, the composition of which he could not then establish. According to Lavoisier, "coal played a cruel joke on him." However, Lavoisier, like many other chemists, did not come up with the idea that the reduction of metal oxides can be carried out by heating with a burning glass. But in the fall of 1774, Joseph Priestley reported that when mercury oxide was reduced with a burning glass, a new type of air was formed - “dephlogisticated air”. Shortly before this oxygen was discovered by Scheele, but the message about this was published with a great delay. Scheele and Priestley explained the phenomenon of oxygen evolution observed by them from the standpoint of the phlogiston theory. Only Lavoisier was able to use the discovery of oxygen as the main argument against the phlogiston theory. In the spring of 1775, Lavoisier reproduced Priestley's experiment. He wanted to get oxygen and check whether oxygen was the component of air due to which combustion or oxidation of metals occurred. Lavoisier managed not only to isolate oxygen, but also to re-obtain mercury oxide. At the same time, Lavoisier determined the weight ratios of the substances entering into this reaction. The scientist was able to prove that the ratios of the amount of substances involved in the oxidation and reduction reactions remain unchanged. The work of Lavoisier produced in chemistry, perhaps, the same revolution as two and a half centuries before the discovery of Copernicus in astronomy. Substances that were previously considered elements, as shown by Lavoisier, turned out to be compounds, consisting in turn of complex “elements”. The discoveries and views of Lavoisier had a tremendous impact not only on the development of chemical theory, but also on the entire system of chemical knowledge. They so transformed the very basis of chemical knowledge and language that the next generations of chemists, in fact, could not even understand the terminology that was used before Lavoisier. On this basis, later they began to believe that it was impossible to talk about “genuine” chemistry until the discoveries of Lavoisier. At the same time, the continuity of chemical research was forgotten. Only the historians of chemistry began to recreate the really existing laws of the development of chemistry. At the same time, it was found out that Lavoisier's “chemical revolution” would have been impossible without the existence of a certain level of chemical knowledge before him.

Lavoisier crowned the development of chemical knowledge with the creation of a new system, which included the most important achievements of chemistry of past centuries. This system, however, in a significantly expanded and corrected form, became the basis of scientific chemistry. In the 80s. 18th century The new system of Lavoisier was recognized by the leading French naturalists - C. Berthollet, A. De Fourcroix and L. Guiton de Morvo. They supported Lavoisier's innovative ideas and, together with him, developed a new chemical nomenclature and terminology. In 1789, Lavoisier outlined the foundations of the system of knowledge he had developed in the textbook "Introductory Course in Chemistry, presented in a new form on the basis of the latest discoveries." Lavoisier divided elements into metals and non-metals, and compounds into binary and ternary. Double compounds formed by metals with oxygen, he attributed to bases, and compounds of non-metals with oxygen - to acids. Ternary compounds obtained by the interaction of acids and bases, he called salts. Lavoisier's system was based on precise qualitative and quantitative research. He used this rather new type of argumentation when studying many controversial problems of chemistry - questions of the theory of combustion, problems of the mutual transformation of elements, which were very relevant during the formation of scientific chemistry. So, to test the idea of ​​the possibility of mutual transformation of elements, Lavoisier heated water in a sealed vessel for several days. As a result, he found an insignificant amount of “earth” in the water, while establishing that the change in the total weight of the vessel along with the water does not occur. Lavoisier explained the formation of “lands” not as a result of their separation from water, but due to the destruction of the walls of the reaction vessel. To answer this question, the Swedish chemist and pharmacist K. Scheele at the same time used qualitative methods of proof, establishing the identity of the allocated “lands” and the material of the vessel. Lavoisier, like Lomonosov, took into account the observations that existed from antiquity on the conservation of the weight of substances and systematically studied the weight ratios of substances participating in a chemical reaction. He drew attention to the fact that, for example, during the combustion of sulfur or the formation of rust on iron, an increase in the weight of the starting substances occurs. This contradicted the phlogiston theory, according to which the hypothetical phlogiston should have been released during combustion. Lavoisier considered the explanation according to which phlogiston had a negative weight to be erroneous, and finally abandoned this idea. Other chemists, such as M. V. Lomonosov or J. Mayow tried to explain the oxidation of elements and the formation of metal oxides (or, as they said then, “lime”) as a process in which air particles combine with some substance. This air can be "pulled back" by recovery. In 1772, Lavoisier collected this air, but could not establish its nature. Priestley was the first to report the discovery of oxygen. In 1775, he succeeded in proving that it is oxygen that combines with the metal and is again released from it when it is reduced, as, for example, when mercury “lime” is formed and reduced. By systematic weighing, it was found that the weight of the metal involved in these transformations does not change. Today, this fact, it would seem, convincingly proves the validity of Lavoisier's assumptions, but then most chemists were skeptical about it. One of the reasons for this attitude was that Lavoisier could not explain the combustion of hydrogen. In 1783, he learned that, using an electric arc, Cavendish proved the formation of water when a mixture of hydrogen and oxygen is burned in a closed vessel. Repeating this experiment, Lavoisier found that the weight of water corresponds to the weight of the starting materials. He then conducted an experiment in which he passed water vapor through iron shavings placed in a highly heated copper tube. The oxygen was combined with the iron shavings, and the hydrogen was collected at the end of the tube. Thus, using the transformations of substances, Lavoisier was able to explain the combustion process both qualitatively and quantitatively, and for this he no longer needed the theory of phlogiston. Priestley and Scheele, who, having discovered oxygen, actually created the basic prerequisites for the emergence of Lavoisier's oxygen theory, themselves firmly adhered to the positions of the phlogiston theory. Cavendish, Priestley, Scheele and some other chemists believed that the discrepancies between the results of experiments and the provisions of the theory of phlogiston could be eliminated by creating additional hypotheses. Reliability and completeness of experimental data, clarity of argumentation and simplicity of presentation contributed to the rapid spread of Lavoisier's system in England, Holland, Germany, Sweden, and Italy. In Germany, Lavoisier's ideas were expounded in two works by Dr. Girtanner, New Chemical Nomenclature in German (1791) and Fundamentals of Antiphlogistic Chemistry (1792). Thanks to Girtanner, the German designations of substances appeared for the first time, corresponding to the new nomenclature, for example, oxygen, hydrogen, nitrogen. Hermbstedt, who worked in Berlin, published in 1792 Lavoisier's textbook translated into German, and M. Klaproth, after he repeated Lavoisier's experiments, recognized the new teaching; Lavoisier's views were also shared by the famous naturalist A. Humboldt.

In the 1790s, Lavoisier's works were published more than once in Germany. Most of the well-known chemists in England, Holland, Sweden, and the waist shared the views of Lavoisier. Often in the historical and scientific literature one can read that it took chemists quite a long time to recognize Lavoisier's theory. However, compared with 200 years of non-recognition of the views of Copernicus by astronomers, the 10-15-year period of discussions in chemistry is not so long. In the last third of the XVIII century. one of the most important was the problem that interested scientists for many centuries: chemists wanted to understand why and in what proportions substances combine with each other. Even Greek philosophers showed interest in this problem, and during the Renaissance, scientists put forward the idea of ​​the affinity of substances and even built series of substances by affinity. Paracelsus wrote that mercury forms amalgams with metals, and for different metals at different rates and in the following sequence: the fastest with gold, then with silver, lead, tin, copper, and finally, the slowest with iron. Paracelsus believed that the reason for this series of chemical affinity is not only the “hatred” and “love” of substances for each other. In accordance with his ideas, metals contain sulfur, and the lower its content, the purer the metals, and the purity of substances largely determines their affinity for each other. G. Stahl explained a number of metal deposition as a result of different content of phlogiston in them. Until the last third of the XVIII century. numerous studies have been directed at arranging substances according to their "affinity", and many chemists have compiled tables accordingly. To explain the different chemical affinity of substances, atomistic ideas were also put forward, and after the end of the 18th - beginning of the 19th centuries. Scientists began to understand the influence of electricity on the course of certain chemical processes, and for the same purpose they tried to use ideas about electricity. Based on them, Berzelius created a dualistic theory of the composition of substances, in accordance with, for example, salts consist of positively and negatively charged “bases” and “acids”: during electrolysis, they are attracted to oppositely charged electrodes and can decompose into elements due to the neutralization of charges . From the second half of the XVIII century. scientists began to pay especially much attention to the question: in what quantitative ratios do substances interact with each other in chemical reactions? It has long been known that acids and bases can neutralize each other. Attempts have also been made to determine the content of acids and bases in salts. T. Bergman and R. Kirwan found that, for example, in the double exchange reaction between chemically neutral potassium sulfate and sodium nitrate, new salts are formed - sodium sulfate and potassium nitrate, which are also chemically neutral. But none of the researchers drew a general conclusion from this observation. In 1767, Cavendish discovered that the same amount of nitric and sulfuric acids, which neutralize the same amount of potassium carbonate, also neutralize the same amount of calcium carbonate. I. Richter was the first to formulate the law of equivalents, the explanation of which was found later from the standpoint of Dalton's atomistic theory.

Richter found that the solution obtained by mixing solutions of two chemically neutral salts is also neutral. He carried out numerous determinations of the amounts of bases and acids, which, when combined, give chemically neutral salts. Richter made the following conclusion: if the same amount of any acid is neutralized by different, strictly defined amounts of different bases, then these amounts of bases are equivalent and neutralized by the same amount of another acid. In modern terms, if, for example, a solution of barium nitrate is added to a solution of potassium sulfate until barium sulfate is completely precipitated, then the solution containing potassium nitrate will also be neutral:

K2SO4 + Ba(NO3)2 = 2KNO3 + BaSO4

Therefore, in the formation of a neutral salt, the following quantities are equivalent to each other: 2K, 1Ba, 1SO4 and 2NO3. Pauling summarized and formulated in its modern form this law of conjunctive weights”: “Weight amounts of two elements (or their integer multiples), which, reacting with the same amount of the third element, react with each other in the same amounts.” At first, Richter's work almost did not attract the attention of researchers, since he still used the terminology of the phlogiston theory. In addition, the series of equivalent weights obtained by the scientist were not clear enough, and the choice of relative amounts of bases he proposed did not have serious evidence. The situation was corrected by E.Fischer, who, among the equivalent weights, Richter chose the equivalent of sulfuric acid as a standard, taking it equal to 100, and, based on this, compiled a table of “relative weights” (equivalents) of compounds. But Fischer's table of equivalents became known only thanks to Bertholla, who, criticizing Fischer, cited these data in his book "Experience in chemical statics" (1803). Berthollet doubted that the composition of chemical compounds is constant. He had reason to. Substances that at the beginning of the XIX century. were considered pure, in fact they were either mixtures or equilibrium systems of various substances, and the quantitative composition of chemical compounds largely depended on the amounts of substances involved in the reactions of their formation.

Some historians of chemistry believe that, like Wenzel, Berthollet also anticipated the main provisions of the law of mass action, which analytically expressed the influence of the quantities interacting on the rate of transformation. The German chemist K. Wenzel in 1777 showed that the rate of dissolution of a metal in acid, measured by the amount of metal dissolved in a certain time, is proportional to the “strength” of the acid. Berthollet did a lot to take into account the influence of the masses of reagents on the course of the transformation. However, between the works of Wenzel and even Berthollet, on the one hand, and the exact formulation of the law of mass action, on the other, there is a qualitative difference. Berthollet's negative attitude towards Richter's neutralization law could not last long, since Proust vigorously opposed Berthollet's provisions. Having done during the years 1799-1807. A lot of analyses, Proust proved that Berthollet made his conclusions about the different composition of the same substances by analyzing mixtures, and not individual substances, that he, for example, did not take into account the water content in some oxides. Proust convincingly proved the constancy of the composition of pure chemical compounds and completed his struggle against the views of Berthollet by establishing the law of the constancy of the composition of substances: the composition of the same substances, regardless of the method of preparation, is the same (constant).

Periodic Law

Considering the history of chemistry, I cannot but mention the discovery of the periodic law. Already in the early stages of the development of chemistry, it was discovered that various elements have special properties. Initially, elements were divided into only two types - metals and non-metals. In 1829, the German chemist Johann Döbereiner discovered the existence of several groups of three elements (triads) with similar chemical properties. Debereiner discovered only 5 triads, these are:

This discovery of the properties of the elements prompted further research by chemists who tried to find rational ways to classify the elements.

In 1865, the English chemist John Newlands (1839-1898) became interested in the problem of periodic repetition of the properties of elements. He arranged the known elements in ascending order of their atomic masses as follows: H Li Be B C N O F Na Mg Al Si P S Cl K Ca Cr Ti Mn Fe

Newlands noticed that in this sequence the eighth element (fluorine) resembles the first (hydrogen), the ninth element resembles the second, and so on. Thus, the properties were repeated every eight elements. However, there were many things wrong with this system of elements:

1) There was no place for new elements in the table.

2) The table did not open the possibility of a scientific approach to the determination of atomic masses and did not allow a choice between their probable best values.

3) Some elements seemed to be badly placed in the table. For example, iron was compared with sulfur (!) etc.

Despite many shortcomings, Newlands' attempt was a step in the right direction. We know that the discovery of the periodic law belongs to Dmitry Ivanovich Mendeleev. Let's look at the history of its discovery. In 1869 N.A. Menshutkin presented to the members of the Russian Chemical Society a small work by D.I. Mendeleev “The relationship of properties with the atomic weight of elements”. (D.I.Mendeleev himself was not present at the meeting.) At this meeting, the work of D.I.Mendeleev was not taken seriously. Paul Walden later wrote: “Big events too often meet with an insignificant response, and the day that should have been a significant day for the young Russian Chemical Society, but in reality turned out to be an everyday day.” DIMendeleev loved bold ideas. The pattern he discovered was that the chemical and physical properties of elements and their compounds are in a periodic dependence on the atomic weights of the elements. Like his predecessors, D.I. Mendeleev singled out the most typical elements. However, he assumed the presence of gaps in the table and dared to argue that they should be filled with elements that have not yet been discovered. At the same time as Mendeleev, Lothar Meyer worked on the same problem and published his work in 1870. However, the priority in the discovery of the periodical deservedly remains with Dmitry Ivanovich Mendeleev, since. even L. Meyer himself did not think of denying the outstanding role of D. I. Mendeleev in the discovery of the periodic law. In his memoirs, L. Meyer indicated that he used the abstract of an article by D. I. Mendeleev when writing his work. In 1870, Mendeleev made some changes to the table: like any pattern based on the bepm` idea, the new system turned out to be viable, since it provided for the possibility of refinements. As I said, the genius of Mendeleev's theory was that he left blanks in his table. Thus, he suggested (or rather was sure) that not all elements were discovered yet. However, Dmitry Ivanovich did not stop there. With the help of the periodic law, he even described the chemical and physical properties of yet undiscovered chemical elements, for example: gallium, germanium, scandium, which were fully confirmed. After that, most scientists were convinced of the correctness of the theory of D.I. Mendeleev. In our time, the periodic law is of great importance. It is used to predict the properties of chemical compounds, reaction products. With the help of the periodic law, and in our time, the properties of the elements are predicted - these are elements that cannot be obtained in significant quantities.

After the works of Lavoisier, Proust, Lomonosov and Mendeleev, many important discoveries in the field of chemistry and physics have already been made in our century. These are works on thermodynamics, the structure of the atom and molecules, electrochemistry - this list can be continued indefinitely. However, the discoveries of Lavoisier and D.I. Mendeleev remain the foundation of chemical knowledge.

Features of modern chemistry

I have divided into sections the features of modern chemistry, I bring them to your attention:

1) The atomic-molecular concept, structural and electronic representations are the basis of modern chemistry.

2) Widespread use - mathematics and computers, - complex physical methods, - classical and quantum mechanics.

3) The special role of theoretical chemistry, computer modeling and computer experiments. Chemistry on paper. Chemistry on display.

4) The dominant role of biochemical and environmental problems.

Conclusion

The unified approach to the structure of very different objects presented in this abstract facilitates a joint comparative discussion of the structure of ordered and disordered phases. The practical importance of such a discussion is due to the fact that while for crystalline substances X-ray diffraction analysis and other diffraction methods provide reliable structural information, for liquid crystals and, especially, liquids, accurate information about the structure (especially about the total structure) is practically inaccessible. Therefore, the interpolation of crystal structure information to other phase states of chemical compounds is of particular importance.

A similar situation arises when the rigorous mathematical approaches developed in the framework of crystallography are extended to objects that are not crystals. In this regard, Bernal and Carlyle introduced the concept of "generalized crystallography". Later similar considerations were expressed by McKay and Finney. Comparative analysis of the structure of various condensed phases can be called "generalized crystal chemistry". An important role in this area will be played by the conservatism of structural fragments (in particular, molecular associates and agglomerates), which was discussed above.

List of used literature

1. Chemical encyclopedic dictionary. M.: Soviet Encyclopedia, 1983.

2. Physical encyclopedic dictionary. M.: Soviet Encyclopedia, 1983.

3. Gordon A., Ford R. Chemist's Companion. M.: Mir, 1976.

4. Afanasiev V.A., Zaikov G.E. Physical methods in chemistry. Moscow: Nauka, 1984. (Series "History of science and technology").

5. Drago R. Physical methods in chemistry. T. 1, 2. M.: Mir, 1981.

6. Vilkov L.V., Pentin Yu.A. Physical methods of research in chemistry. Structural methods and optical spectroscopy. M: Higher School, 1987.

7. Vilkov L.V., Pentin Yu.A. Physical methods of research in chemistry. Resonance and electro-optical methods. Moscow: Higher school, 1989.

8. Journal of the All-Union Chemical Society. DI. Mendeleev. 1985. T. 30. N 2.

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The need for interdisciplinary connections in teaching is undeniable. Their consistent and systematic implementation significantly enhances the effectiveness of the educational process, forms a dialectical way of thinking of students. In addition, interdisciplinary connections are an indispensable didactic condition for the development of students' interest in knowledge of the foundations of the sciences, including the natural ones.

This is what the analysis of the lessons of physics, chemistry and biology showed: in most cases, teachers are limited to only fragmentary inclusion of interdisciplinary connections (ILC). In other words, they only resemble facts, phenomena or patterns from related subjects.

Teachers rarely include students in independent work on the application of interdisciplinary knowledge and skills in the study of program material, as well as in the process of independently transferring previously acquired knowledge to a new situation. The consequence is the inability of the children to carry out the transfer and synthesis of knowledge from related subjects. There is no continuity in education. Thus, biology teachers continuously "run ahead", introducing students to various physical and chemical processes occurring in living organisms, without relying on physical and chemical concepts, which does little to consciously master biological knowledge.

A general analysis of the textbooks allows us to note that many facts and concepts are presented in them repeatedly in different disciplines, and their repeated presentation practically adds little to the students' knowledge. Moreover, often the same concept is interpreted differently by different authors, thereby complicating the process of their assimilation. Often, textbooks use terms that are little known to students, and there are few tasks of an interdisciplinary nature. Many authors almost do not mention that some phenomena, concepts have already been studied in the courses of related subjects, do not indicate that these concepts will be considered in more detail when studying another subject. An analysis of the current programs in natural disciplines allows us to conclude that interdisciplinary connections are not given due attention. Only in general biology programs for grades 10-11 (V.B. Zakharov); “Man” (V.I. Sivoglazov) has special sections “Intersubject communications” with an indication of physical and chemical concepts, laws and theories that are the foundation for the formation of biological concepts. There are no such sections in physics and chemistry curricula, and teachers themselves have to set the necessary MPS. And this is a difficult task - to coordinate the material of related subjects in such a way as to ensure unity in the interpretation of concepts.

Interdisciplinary connections of physics, chemistry and biology could be established much more often and more efficiently. The study of processes occurring at the molecular level is possible only if the knowledge of molecular biophysics, biochemistry, biological thermodynamics, elements of cybernetics that complement each other is involved. This information is dispersed throughout the courses of physics and chemistry, but only in the course of biology does it become possible to consider issues that are difficult for students, using interdisciplinary connections. In addition, it becomes possible to work out concepts common to the cycle of natural disciplines, such as matter, interaction, energy, discreteness, etc.

When studying the basics of cytology, interdisciplinary connections are established with the elements of knowledge of biophysics, biochemistry, and biocybernetics. So, for example, a cell can be represented as a mechanical system, and in this case its mechanical parameters are considered: density, elasticity, viscosity, etc. The physicochemical characteristics of a cell allow us to consider it as a dispersed system, a set of electrolytes, semipermeable membranes. Without combining "such images" it is hardly possible to form the concept of a cell as a complex biological system. In the "Fundamentals of Genetics and Breeding" section, the MPS is established between organic chemistry (proteins, nucleic acids) and physics (fundamentals of molecular-kinetic theory, discreteness of electric charge, etc.).

The teacher must plan in advance the possibility of implementing both previous and future connections of biology with the corresponding branches of physics. Information on mechanics (properties of tissues, movement, elastic properties of blood vessels and the heart, etc.) makes it possible to consider physiological processes; about the electromagnetic field of the biosphere - to explain the physiological functions of organisms. Many questions of biochemistry are of the same importance. The study of complex biological systems (biogeocenoses, biosphere) is associated with the need to acquire knowledge about the ways of exchanging information between individuals (chemical, optical, sound), but for this, again, it is necessary to use knowledge of physics and chemistry.

The use of interdisciplinary connections is one of the most difficult methodological tasks of a chemistry teacher. It requires knowledge of the content of programs and textbooks in other subjects. The implementation of interdisciplinary connections in the practice of teaching involves the cooperation of a chemistry teacher with teachers of other subjects.

A chemistry teacher develops an individual plan for the implementation of interdisciplinary connections in a chemistry course. The method of creative work of the teacher in this regard goes through the following stages:

• 1. Studying the program in chemistry, its section "Intersubject communications", programs and textbooks in other subjects, additional scientific, popular science and methodological literature;
• 2. Lesson planning of interdisciplinary connections using course and thematic plans;
• 3. Development of means and methods for implementing interdisciplinary connections in specific lessons (formulation of interdisciplinary cognitive tasks, homework, selection of additional literature for students, preparation of necessary textbooks and visual aids in other subjects, development of methodological methods for their use);
• 4. Development of a methodology for the preparation and conduct of complex forms of organization of education (generalizing lessons with interdisciplinary connections, complex seminars, excursions, circle classes, electives on interdisciplinary topics, etc.);
• 5. Development of methods for monitoring and evaluating the results of the implementation of interdisciplinary connections in education (questions and tasks to identify students' skills to establish interdisciplinary connections).

Planning interdisciplinary connections allows the teacher to successfully implement their methodological, educational, developmental, educational and constructive functions; provide for all the variety of their types in the classroom, in the home and extracurricular work of students.

To establish interdisciplinary connections, it is necessary to select materials, that is, to identify those topics of chemistry that are closely intertwined with topics from courses of other subjects.

Course planning involves a brief analysis of the content of each educational topic of the course, taking into account intra-subject and inter-subject communications.

For the successful implementation of interdisciplinary connections, a teacher of chemistry, biology and physics must know and be able to:

cognitive component

• the content and structure of related courses;
• · coordinate the study of related subjects in time;
• Theoretical foundations of the problem of MPS (types of classifications of MPS, methods for their implementation, functions of MPS, main components of MPS, etc.);
• ensure continuity in the formation of general concepts, the study of laws and theories; use common approaches to the formation of skills and abilities of educational work among students, continuity in their development;
• reveal the relationship of phenomena of different nature, studied by related subjects;
• · to formulate specific teaching and educational tasks based on the goals of the MPS of physics, chemistry, biology;
• · to analyze educational information of related disciplines; the level of formation of interdisciplinary knowledge and skills of students; the effectiveness of the applied teaching methods, forms of training sessions, teaching aids based on the MPS.

structural component

• · to form a system of goals and objectives that contribute to the implementation of the MPS;
• · to plan teaching and educational work aimed at the implementation of the MPS; identify the educational and developmental opportunities of the MPS;
• · design the content of interdisciplinary and integrative lessons, comprehensive seminars, etc. Anticipate the difficulties and errors that students may encounter in the formation of interdisciplinary knowledge and skills;
• · to design methodological equipment of lessons, to choose the most rational forms and methods of teaching on the basis of MPS;
• plan various forms of organization of educational and cognitive activities; design didactic equipment for training sessions. Organizational Component
• organize educational and cognitive activities of students depending on the goals and objectives, on their individual characteristics;
• · to form the cognitive interest of students in the subjects of the natural cycle on the basis of MPS;
• organize and manage the work of intersubject circles and electives; master the skills of NOT; methods of managing students' activities.

Communicative component

• The psychology of communication psychological and pedagogical foundations for the formation of interdisciplinary knowledge and skills; psychological characteristics of students;
• to navigate in psychological situations in the student team; establish interpersonal relationships in the classroom;
• · establish interpersonal relationships with teachers of related disciplines in the joint implementation of the MPS.

Orientation Component

• · theoretical bases of activity on establishment of MPS at studying of subjects of a natural cycle;
• · navigate the educational material of related disciplines; in the system of methods and forms of training that contribute to the successful implementation of the MPS.

Mobilization component

• · adapt pedagogical technologies for the implementation of the MPS of physics, chemistry, biology; offer the author's or choose the most appropriate methodology for the formation of interdisciplinary knowledge and skills in the process of teaching physics, chemistry, biology;
• · develop author's or adapt traditional methods of solving problems of interdisciplinary content;
• · master the methodology of conducting complex forms of training sessions; be able to organize self-educational activities to master the technology of implementing MPS in teaching physics, chemistry and biology.

Research component

• · to analyze and summarize the experience of their work on the implementation of the MPS; generalize and implement the experience of their colleagues; conduct a pedagogical experiment, analyze their results;
• · to organize work on the methodological theme of the IPU.

This professiogram can be considered both as a basis for building the process of preparing teachers of physics, chemistry and biology for the implementation of the MPS, and as a criterion for assessing the quality of their training.

The use of interdisciplinary connections in the study of chemistry allows students to get acquainted from the first year with the subjects that they will study in senior courses: electrical engineering, management, economics, materials science, machine parts, industrial ecology, etc. By pointing out in chemistry lessons why and in what subjects students will need this or that knowledge, the teacher motivates the memorization of the material not only for one lesson, to get an assessment, but also changes the personal interests of students of non-chemical specialties.

Relationship between chemistry and physics

Along with the processes of differentiation of chemical science itself, chemistry is currently undergoing integration processes with other branches of natural science. The interrelations between physics and chemistry are developing especially intensively. This process is accompanied by the emergence of more and more related physical and chemical branches of knowledge.

The whole history of the interaction of chemistry and physics is full of examples of the exchange of ideas, objects and methods of research. At different stages of its development, physics supplied chemistry with concepts and theoretical concepts that had a strong impact on the development of chemistry. At the same time, the more complicated chemical research became, the more the equipment and calculation methods of physics penetrated into chemistry. The need to measure the thermal effects of a reaction, the development of spectral and X-ray diffraction analysis, the study of isotopes and radioactive chemical elements, the crystal lattices of matter, molecular structures required the creation and led to the use of the most complex physical instruments - spectroscopes, mass spectrographs, diffraction gratings, electron microscopes, etc.

The development of modern science has confirmed the deep connection between physics and chemistry. This connection is of a genetic nature, that is, the formation of atoms of chemical elements, their combination into molecules of matter occurred at a certain stage in the development of the inorganic world. Also, this connection is based on the commonality of the structure of specific types of matter, including the molecules of substances, which ultimately consist of the same chemical elements, atoms and elementary particles. The emergence of the chemical form of motion in nature caused the further development of ideas about the electromagnetic interaction studied by physics. On the basis of the periodic law, progress is now being made not only in chemistry, but also in nuclear physics, on the border of which such mixed physico-chemical theories as the chemistry of isotopes and radiation chemistry arose.

Chemistry and physics study almost the same objects, but only each of them sees its own side in these objects, its own subject of study. So, the molecule is the subject of study not only of chemistry, but also of molecular physics. If the former studies it from the point of view of the laws of formation, composition, chemical properties, bonds, conditions for its dissociation into constituent atoms, then the latter statistically studies the behavior of the masses of molecules, which determines thermal phenomena, various states of aggregation, transitions from gaseous to liquid and solid phases and vice versa , phenomena not associated with a change in the composition of molecules and their internal chemical structure. The accompaniment of each chemical reaction by the mechanical movement of masses of reactant molecules, the release or absorption of heat due to the breaking or formation of bonds in new molecules convincingly testify to the close connection between chemical and physical phenomena. Thus, the energy of chemical processes is closely related to the laws of thermodynamics. Chemical reactions that release energy, usually in the form of heat and light, are called exothermic. There are also endothermic reactions that absorb energy. All of the above does not contradict the laws of thermodynamics: in the case of combustion, energy is released simultaneously with a decrease in the internal energy of the system. In endothermic reactions, the internal energy of the system increases due to the influx of heat. By measuring the amount of energy released during a reaction (the heat effect of a chemical reaction), one can judge the change in the internal energy of the system. It is measured in kilojoules per mole (kJ/mol).

One more example. Hess' law is a special case of the first law of thermodynamics. It states that the thermal effect of a reaction depends only on the initial and final states of the substances and does not depend on the intermediate stages of the process. Hess's law makes it possible to calculate the thermal effect of a reaction in cases where its direct measurement is for some reason impossible.

With the advent of the theory of relativity, quantum mechanics and the theory of elementary particles, even deeper connections between physics and chemistry were revealed. It turned out that the key to explaining the essence of the properties of chemical compounds, the very mechanism of the transformation of substances lies in the structure of atoms, in the quantum mechanical processes of its elementary particles and especially the electrons of the outer shell. molecules of organic and inorganic compounds, etc.

In the field of contact between physics and chemistry, such a relatively young section of the main sections of chemistry as physical chemistry arose and is successfully developing, which took shape at the end of the 19th century. as a result of successful attempts to quantitatively study the physical properties of chemicals and mixtures, the theoretical explanation of molecular structures. The experimental and theoretical basis for this was the work of D.I. Mendeleev (the discovery of the Periodic Law), Van't Hoff (the thermodynamics of chemical processes), S. Arrhenius (the theory of electrolytic dissociation), etc. The subject of its study was general theoretical questions concerning the structure and properties of the molecules of chemical compounds, the processes of transformation of substances in connection with the mutual dependence of their physical properties, the study of the conditions for the occurrence of chemical reactions and the physical phenomena that take place in this case. Now physical chemistry is a diversified science that closely links physics and chemistry.

In physical chemistry itself, by now, electrochemistry, the study of solutions, photochemistry, and crystal chemistry have stood out and fully developed as independent sections with their own special methods and objects of study. At the beginning of the XX century. Colloidal chemistry, which grew up in the depths of physical chemistry, also stood out as an independent science. Since the second half of the XX century. In connection with the intensive development of the problems of nuclear energy, the latest branches of physical chemistry arose and received great development - high-energy chemistry, radiation chemistry (the subject of its study are reactions occurring under the action of ionizing radiation), and isotope chemistry.

Physical chemistry is now regarded as the broadest general theoretical foundation of all chemical science. Many of her teachings and theories are of great importance for the development of inorganic and especially organic chemistry. With the advent of physical chemistry, the study of matter began to be carried out not only by traditional chemical methods of research, not only from the point of view of its composition and properties, but also from the side of the structure, thermodynamics and kinetics of the chemical process, as well as from the side of the connection and dependence of the latter on the impact of phenomena inherent in other forms of movement (light and radiation exposure, light and heat exposure, etc.).

It is noteworthy that in the first half of the XX century. there was a boundary between chemistry and new branches of physics (quantum mechanics, electronic theory of atoms and molecules) science, which later became known as chemical physics. She widely applied the theoretical and experimental methods of the latest physics to the study of the structure of chemical elements and compounds, and especially the mechanism of reactions. Chemical physics studies the interconnection and mutual transition of the chemical and subatomic forms of the motion of matter.

In the hierarchy of basic sciences given by F. Engels, chemistry is directly adjacent to physics. This neighborhood provided the speed and depth with which many branches of physics fruitfully wedged into chemistry. Chemistry borders, on the one hand, with macroscopic physics - thermodynamics, physics of continuous media, and on the other hand - with microphysics - static physics, quantum mechanics.

It is well known how fruitful these contacts were for chemistry. Thermodynamics gave rise to chemical thermodynamics - the study of chemical equilibrium. Static physics formed the basis of chemical kinetics - the study of the rates of chemical transformations. Quantum mechanics revealed the essence of Mendeleev's Periodic Law. The modern theory of chemical structure and reactivity is quantum chemistry, i.e. application of the principles of quantum mechanics to the study of molecules and "X transformations".

Another evidence of the fruitful influence of physics on chemical science is the ever-expanding use of physical methods in chemical research. The striking progress in this area is especially clearly seen in the example of spectroscopic methods. More recently, from the infinite range of electromagnetic radiation, chemists used only a narrow region of the visible and adjacent areas of the infrared and ultraviolet ranges. The discovery by physicists of the phenomenon of magnetic resonance absorption led to the emergence of nuclear magnetic resonance spectroscopy, the most informative modern analytical method and method for studying the electronic structure of molecules, and electron paramagnetic resonance spectroscopy, a unique method for studying unstable intermediate particles - free radicals. In the short-wavelength region of electromagnetic radiation, X-ray and gamma-ray resonance spectroscopy arose, which owes its appearance to the discovery of Mössbauer. The development of synchrotron radiation has opened up new prospects for the development of this high-energy branch of spectroscopy.

It would seem that the entire electromagnetic range has been mastered, and it is difficult to expect further progress in this area. However, lasers appeared - sources unique in their spectral intensity - and along with them fundamentally new analytical possibilities. Among them is laser magnetic resonance, a rapidly developing highly sensitive method for detecting radicals in a gas. Another truly fantastic possibility is the piece registration of atoms with a laser - a technique based on selective excitation, which makes it possible to register only a few atoms of a foreign impurity in a cell. Striking opportunities for studying the mechanisms of radical reactions were provided by the discovery of the phenomenon of chemical polarization of nuclei.

Now it is difficult to name an area of ​​modern physics that would not directly or indirectly influence chemistry. Take, for example, the physics of unstable elementary particles, which is far from the world of molecules built from nuclei and electrons. It may seem surprising that special international conferences discuss the chemical behavior of atoms containing a positron or muon, which, in principle, cannot give stable compounds. However, the unique information about ultrafast reactions, which such atoms allow to obtain, fully justifies this interest.

Looking back at the history of the relationship between physics and chemistry, we see that physics has played an important, sometimes decisive role in the development of theoretical concepts and research methods in chemistry. The degree of recognition of this role can be assessed by viewing, for example, the list of Nobel Prize winners in chemistry. Not less than a third of this list are the authors of the largest achievements in the field of physical chemistry. Among them are those who discovered radioactivity and isotopes (Rutherford, M. Curie, Soddy, Aston, Joliot-Curie, etc.), laid the foundations of quantum chemistry (Pauling and Mulliken) and modern chemical kinetics (Hinshelwood and Semenov), developed new physical methods (Debye, Geyerovsky, Eigen, Norrish and Porter, Herzberg).

Finally, one should keep in mind the decisive importance that the productivity of the scientist's labor begins to play in the development of science. Physical methods have played and continue to play a revolutionary role in chemistry in this respect. It suffices to compare, for example, the time that an organic chemist spent on establishing the structure of a synthesized compound by chemical means and that he spends now, owning an arsenal of physical methods. Undoubtedly, this reserve of applying the achievements of physics is far from being used sufficiently.

Let's sum up some results. We see that physics on an ever larger scale, and more and more fruitfully intrudes into chemistry. Physics reveals the essence of qualitative chemical regularities, supplies chemistry with perfect research tools. The relative volume of physical chemistry is growing, and there are no reasons that can slow down this growth.

Relationship between chemistry and biology

It is well known that for a long time chemistry and biology went their own way, although the long-standing dream of chemists was the creation of a living organism in the laboratory.

A sharp strengthening of the relationship between chemistry and biology occurred as a result of the creation of A.M. Butlerov's theory of the chemical structure of organic compounds. Guided by this theory, organic chemists entered into competition with nature. Subsequent generations of chemists showed great ingenuity, work, imagination and creative search for a directed synthesis of matter. Their intention was not only to imitate nature, they wanted to surpass it. And today we can confidently state that in many cases this has been achieved.

The progressive development of science in the 19th century, which led to the discovery of the structure of the atom and a detailed knowledge of the structure and composition of the cell, opened up practical possibilities for chemists and biologists to work together on the chemical problems of the theory of the cell, on questions about the nature of chemical processes in living tissues, and on the conditionality of biological functions. chemical reactions.

If you look at the metabolism in the body from a purely chemical point of view, as A.I. Oparin, we will see a set of a large number of relatively simple and uniform chemical reactions that combine with each other in time, do not occur randomly, but in strict sequence, resulting in the formation of long chains of reactions. And this order is naturally directed towards constant self-preservation and self-reproduction of the entire living system as a whole in given environmental conditions.

In a word, such specific properties of living things as growth, reproduction, mobility, excitability, the ability to respond to changes in the external environment, are associated with certain complexes of chemical transformations.

The significance of chemistry among the sciences that study life is exceptionally great. It was chemistry that revealed the most important role of chlorophyll as the chemical basis of photosynthesis, hemoglobin as the basis of the respiration process, the chemical nature of the transmission of nervous excitation was established, the structure of nucleic acids was determined, etc. But the main thing is that, objectively, chemical mechanisms lie at the very basis of biological processes, the functions of living things. All the functions and processes occurring in a living organism can be expressed in the language of chemistry, in the form of specific chemical processes.

Of course, it would be wrong to reduce the phenomena of life to chemical processes. This would be a gross mechanistic simplification. And a clear evidence of this is the specificity of chemical processes in living systems in comparison with non-living ones. The study of this specificity reveals the unity and interrelation of the chemical and biological forms of the motion of matter. Other sciences that arose at the intersection of biology, chemistry and physics speak of the same: biochemistry is the science of metabolism and chemical processes in living organisms; bioorganic chemistry - the science of the structure, functions and ways of synthesis of compounds that make up living organisms; physical and chemical biology as a science of the functioning of complex information transmission systems and regulation of biological processes at the molecular level, as well as biophysics, biophysical chemistry and radiation biology.

The major achievements of this process were the determination of chemical products of cellular metabolism (metabolism in plants, animals, microorganisms), the establishment of biological pathways and cycles of biosynthesis of these products; their artificial synthesis was implemented, the discovery of the material foundations of the regulatory and hereditary molecular mechanism was made, and the significance of chemical processes was clarified to a large extent in the energy processes of the cell and living organisms in general.

Nowadays, for chemistry, the application of biological principles is becoming especially important, in which the experience of adapting living organisms to the conditions of the Earth over many millions of years, the experience of creating the most advanced mechanisms and processes is concentrated. There are already certain achievements along this path.

More than a century ago, scientists realized that the basis of the exceptional efficiency of biological processes is biocatalysis. Therefore, chemists set themselves the goal of creating a new chemistry based on the catalytic experience of living nature. A new control of chemical processes will appear in it, where the principles of the synthesis of similar molecules will be applied, catalysts with such a variety of qualities will be created on the principle of enzymes that will far surpass those existing in our industry.

Despite the fact that enzymes have common properties inherent in all catalysts, however, they are not identical to the latter, since they function within living systems. Therefore, all attempts to use the experience of living nature to accelerate chemical processes in the inorganic world face serious limitations. So far, we can only talk about modeling some of the functions of enzymes and using these models for the theoretical analysis of the activity of living systems, as well as the partial practical application of isolated enzymes to speed up some chemical reactions.

Here, the most promising direction, obviously, is research focused on the application of the principles of biocatalysis in chemistry and chemical technology, for which it is necessary to study the entire catalytic experience of living nature, including the experience of the formation of the enzyme itself, the cell, and even the organism.

The theory of self-development of elementary open catalytic systems, put forward in the most general form by Professor A.P. Rudenko in 1964, is a general theory of chemical evolution and biogenesis. It solves questions about the driving forces and mechanisms of the evolutionary process, that is, about the laws of chemical evolution, about the selection of elements and structures and their causation, about the height of chemical organization and the hierarchy of chemical systems as a consequence of evolution.

The theoretical core of this theory is the position that chemical evolution is a self-development of catalytic systems and, therefore, catalysts are the evolving substance. In the course of the reaction, there is a natural selection of those catalytic centers that have the greatest activity. Self-development, self-organization and self-complication of catalytic systems occurs due to the constant influx of transformable energy. And since the main source of energy is the basic reaction, the catalytic systems developing on the basis of exothermic reactions receive the maximum evolutionary advantages. Hence, the basic reaction is not only a source of energy, but also a tool for selecting the most progressive evolutionary changes in catalysts.

Developing these views, A.P. Rudenko formulated the basic law of chemical evolution, according to which those paths of evolutionary changes of the catalyst are formed with the greatest speed and probability, on which the maximum increase in its absolute activity occurs.

A practical consequence of the theory of self-development of open catalytic systems is the so-called "non-stationary technology", that is, technology with changing reaction conditions. Today, researchers come to the conclusion that the stationary regime, the reliable stabilization of which seemed to be the key to the high efficiency of the industrial process, is only a special case of the non-stationary regime. At the same time, many non-stationary regimes were found that contribute to the intensification of the reaction.

At present, the prospects for the emergence and development of new chemistry are already visible, on the basis of which low-waste, waste-free and energy-saving industrial technologies will be created.

Today, chemists have come to the conclusion that, using the same principles on which the chemistry of organisms is built, in the future (without exactly repeating nature) it will be possible to build a fundamentally new chemistry, a new control of chemical processes, where the principles of synthesis of similar molecules will be applied. It is envisaged to create converters that use sunlight with high efficiency, converting it into chemical and electrical energy, as well as chemical energy into light of great intensity.

Conclusion

Modern chemistry is represented by many different directions in the development of knowledge about the nature of matter and methods of its transformation. At the same time, chemistry is not just a sum of knowledge about substances, but a highly ordered, constantly evolving system of knowledge that has its place among other natural sciences.

Chemistry studies the qualitative diversity of material carriers of chemical phenomena, the chemical form of the motion of matter. Although structurally it intersects in certain areas with physics, biology, and other natural sciences, it retains its specificity.

One of the most significant objective grounds for singling out chemistry as an independent natural science discipline is the recognition of the specificity of the chemistry of the relationship of substances, which manifests itself primarily in a complex of forces and various types of interactions that determine the existence of two and polyatomic compounds. This complex is usually characterized as a chemical bond that arises or breaks during the interaction of particles of the atomic level of the organization of matter. The occurrence of a chemical bond is characterized by a significant redistribution of the electron density in comparison with the simple position of the electron density of unbound atoms or atomic fragments that are close to the bond distance. This feature most accurately separates the chemical bond from various manifestations of intermolecular interactions.

The ongoing steady increase in the role of chemistry as a science within natural science is accompanied by the rapid development of fundamental, complex and applied research, the accelerated development of new materials with desired properties and new processes in the field of production technology and processing of substances.

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1. Natural science as a science about Nature. Basic natural sciences and their relationship

2. Quantum physics and its basic principles. The world of particles and antiparticles

3. Mechanics. Basic laws of classical mechanics

1. Natural science as a science about Nature. Basic natural sciences and their relationship

natural science the science of nature . In the modern world, natural science is a system of natural sciences, or the so-called natural sciences, taken in mutual connection and based, as a rule, on mathematical methods of describing objects of study.

Natural Science:

One of the three main areas of scientific knowledge about nature, society and thought;

Is the theoretical basis of industrial and agricultural technology and medicine

It is the natural scientific foundation of the picture of the world.

Being the foundation for the formation of a scientific picture of the world, natural science is a certain system of views on one or another understanding of natural phenomena or processes. And if such a system of views takes on a single, defining character, then, as a rule, it is called a concept. Over time, new empirical facts and generalizations appear, and the system of views on the understanding of processes changes, new concepts appear.

If we consider the subject area of ​​natural science as broadly as possible, then it includes:

Various forms of motion of matter in nature;

Their material carriers, which form a "ladder" of levels of the structural organization of matter;

Their relationship, internal structure and genesis.

But it was not always so. The problems of the device, the origin of the organization of everything that is in the Universe (Cosmos), in the 4th-6th centuries belonged to "physics". And Aristotle called those who dealt with these problems simply "physicists" or "physiologists", because. the ancient Greek word "physics" is equal to the word "nature".

In modern natural science, nature is considered not in the abstract, outside of human activity, but concretely, as being under the influence of man, because its knowledge is achieved not only by speculative, theoretical, but also by the practical production activity of people.

Thus, natural science as a reflection of nature in human consciousness is being improved in the process of its active transformation in the interests of society.

The goals of natural science follow from this:

Revealing the essence of natural phenomena, their laws, and on this basis, the prediction or creation of new phenomena;

The ability to use in practice the known laws, forces and substances of nature.

It follows that if society is interested in training highly qualified specialists who are able to productively use their knowledge, then the goal of studying the concepts of modern natural science is not to study physics, chemistry, biology, etc., but to reveal those hidden connections that create the organic unity of physical , chemical, biological phenomena.

The natural sciences are:

Sciences about space, its structure and evolution (astronomy, cosmology, astrophysics, cosmochemistry, etc.);

Physical sciences (physics) - sciences about the deepest laws of natural objects and at the same time - about the simplest forms of their changes;

Chemical sciences (chemistry) - sciences about substances and their transformations

Biological sciences (biology) - life sciences;

Earth sciences (geonomy) - this includes: geology (the science of the structure of the earth's crust), geography (the science of the size and shape of the earth's surface), etc.

The listed sciences do not exhaust the whole of natural science, because. man and human society are inseparable from nature, they are part of it.

A person's desire for knowledge of the surrounding world is expressed in various forms, methods and directions of his research activities. Each of the main parts of the objective world - nature, society and man - is studied by its own separate sciences. The totality of scientific knowledge about nature is formed by natural science, that is, knowledge about nature ("nature" - nature - and "knowledge").

Natural science is a set of natural sciences that have as the subject of their research various phenomena and processes of nature, the laws of their evolution. In addition, natural science is a separate independent science of nature as a whole. It allows you to study any object of the world around us more deeply than any one of the natural sciences can do. Therefore, natural science, along with the sciences of society and thinking, is the most important part of human knowledge. It includes both the activity of obtaining knowledge and its results, i.e., the system of scientific knowledge about natural processes and phenomena.

The specificity of the subject of natural science is that it studies the same natural phenomena from the standpoint of several sciences at once, revealing the most general patterns and trends, considering Nature as if from above. This is the only way to present Nature as a single integral system, to reveal the foundations on which the whole variety of objects and phenomena of the surrounding world is built. The result of such studies is the formulation of the basic laws that connect the micro-, macro- and mega-worlds, the Earth and the Cosmos, physical and chemical phenomena with life and mind in the Universe. The main objective of this course is the understanding of Nature as a single integrity, the search for deeper relationships between physical, chemical and biological phenomena, as well as the identification of hidden connections that create the organic unity of these phenomena.

The structure of natural science is a complex branched system of knowledge, all parts of which are in relation to hierarchical subordination. This means that the system of natural sciences can be represented as a kind of ladder, each step of which is the foundation for the science that follows it, and in turn is based on the data of the previous science.

So, the basis, the foundation of all natural sciences is physics, the subject of which is bodies, their movements, transformations and forms of manifestation at various levels.

The next step in the hierarchy is chemistry, which studies chemical elements, their properties, transformations and compounds.

In turn, chemistry underlies biology - the science of the living, which studies the cell and everything derived from it. Biology is based on knowledge about matter, chemical elements.

Earth sciences (geology, geography, ecology, etc.) are the next degree of the structure of natural science. They consider the structure and development of our planet, which is a complex combination of physical, chemical and biological phenomena and processes.

This grandiose pyramid of knowledge about Nature is completed by cosmology, which studies the Universe as a whole. Part of this knowledge is astronomy and cosmogony, which study the structure and origin of planets, stars, galaxies, etc. At this level, there is a new return to physics. This allows us to talk about the cyclical, closed nature of natural science, which obviously reflects one of the most important properties of Nature itself.

The most complicated processes of differentiation and integration of scientific knowledge are going on in science. The differentiation of science is the allocation within any science of narrower, private areas of research, their transformation into independent sciences. So, within physics, solid-state physics and plasma physics stood out.

The integration of science is the emergence of new sciences at the junctions of the old ones, the manifestation of the processes of unification of scientific knowledge. An example of this kind of sciences are: physical chemistry, chemical physics, biophysics, biochemistry, geochemistry, biogeochemistry, astrobiology, etc.

Natural science is a set of natural sciences that have as the subject of their research various phenomena and processes of nature, the laws of their evolution.

Metaphysics (Greek meta ta physika - after physics) is a philosophical doctrine of supersensitive (inaccessible to experience) principles of being.

Naturphilosophy is a speculative interpretation of nature, the perception of it as a whole.

The system approach is the idea of ​​the world as a set of multi-level systems connected by relations of hierarchical subordination.

2. Quantum physics and its main applicationsincipi. The world of particles and antiparticles

In 1900 the German physicist M. Planck demonstrated by his research that the radiation of energy occurs discretely, in certain portions - quanta, the energy of which depends on the frequency of the light wave. The theory of M. Planck did not need the concept of ether and overcame the contradictions and difficulties of J. Maxwell's electrodynamics. The experiments of M. Planck led to the recognition of the dual nature of light, which has both corpuscular and wave properties. It is clear that such a conclusion was incompatible with the ideas of classical physics. The theory of M. Planck marked the beginning of a new quantum physics, which describes the processes occurring in the microcosm.

Based on the ideas of M. Planck, A. Einstein proposed the photon theory of light, according to which light is a stream of moving quanta. The quantum theory of light (photon theory) considers light as a wave with a discontinuous structure. Light is a stream of indivisible light quanta - photons. A. Einstein's hypothesis made it possible to explain the phenomenon of the photoelectric effect - the knocking out of electrons from a substance under the influence of electromagnetic waves. It became clear that an electron is knocked out by a photon only if the photon energy is sufficient to overcome the force of interaction of electrons with the atomic nucleus. In 1922, A. Einstein received the Nobel Prize for the creation of the quantum theory of light.

The explanation of the process of the photoelectric effect was based, in addition to the quantum hypothesis of M. Planck, also on new ideas about the structure of the atom. In 1911 English physicist E. Rutherford proposed a planetary model of the atom. The model represented an atom as a positively charged nucleus around which negatively charged electrons revolve. The force arising from the movement of electrons in orbits is balanced by the attraction between the positively charged nucleus and the negatively charged electrons. The total charge of an atom is zero because the charges of the nucleus and electrons are equal to each other. Almost the entire mass of an atom is concentrated in its nucleus, and the mass of electrons is negligible. Using the planetary model of the atom, the phenomenon of deflection of alpha particles when passing through the atom was explained. Since the size of the atom is large compared to the size of the electrons and the nucleus, the alpha particle passes through it without obstacles. The deflection is observed only when the alpha particle passes close to the nucleus, in which case the electrical repulsion causes it to veer sharply from its original path. In 1913 Danish physicist N. Bohr proposed a more perfect model of the atom, supplementing the ideas of E. Rutherford with new hypotheses. The postulates of N. Bohr were as follows:

1. Postulate of stationary states. An electron makes stable orbital motions in stationary orbits in an atom, neither emitting nor absorbing energy.

2. Rule of frequencies. An electron is able to move from one stationary orbit to another, while emitting or absorbing energy. Since the energies of the orbits are discrete and constant, when moving from one of them to another, a certain portion of energy is always emitted or absorbed.

The first postulate made it possible to answer the question: why do electrons, when moving in circular orbits around the nucleus, do not fall on it, i.e. Why does an atom remain stable?

The second postulate explained the discontinuity of the electron radiation spectrum. The quantum postulates of N. Bohr meant the rejection of classical physical concepts, which until that time were considered absolutely true.

Despite the rapid recognition, N. Bohr's theory still did not give answers to many questions. In particular, scientists have not been able to accurately describe multi-electron atoms. It turned out that this is due to the wave nature of electrons, which are erroneous to represent as solid particles moving in certain orbits.

In reality, the states of an electron can change. N. Bohr suggested that microparticles are neither a wave nor a corpuscle. With one type of measuring instruments, they behave like a continuous field, with another - like discrete material particles. It turned out that the idea of ​​the exact orbits of the movement of electrons is also erroneous. Due to their wave nature, the electrons are rather "smeared" over the atom, and rather unevenly. At certain points, their charge density reaches a maximum. The curve connecting the points of maximum electron charge density is its "orbit".

In the 20-30s. W. Heisenberg and L. de Broglie laid the foundations of a new theory - quantum mechanics. In 1924 in "Light and Matter"

L. de Broglie suggested the universality of wave-particle duality, according to which all micro-objects can behave both as waves and as particles. Based on the already established dual (corpuscular and wave) nature of light, he expressed the idea of ​​the wave properties of any material particles. So, for example, an electron behaves like a particle when it moves in an electromagnetic field, and like a wave when it passes through a crystal. This idea is called corpuscular-wave dualism. The principle of corpuscular-wave dualism establishes the unity of discreteness and continuity of matter.

In 1926 E. Schrödinger, based on the ideas of L. de Broglie, built wave mechanics. In his opinion, quantum processes are wave processes, therefore the classical image of a material point occupying a certain place in space is adequate only for macroprocesses and is completely wrong for the microworld. In the microcosm, a particle exists both as a wave and as a corpuscle. In quantum mechanics, an electron can be thought of as a wave whose length depends on its speed. E. Schrödinger's equation describes the motion of microparticles in force fields and takes into account their wave properties.

Based on these ideas in 1927. the principle of complementarity was formulated, according to which wave and corpuscular descriptions of processes in the microcosm do not exclude, but complement each other, and only in unity give a complete description. When accurately measuring one of the additional quantities, the other undergoes an uncontrolled change. The concepts of particle and wave not only complement each other, but at the same time contradict each other. They are complementary pictures of what is happening. The statement of corpuscular-wave dualism became the basis of quantum physics.

In 1927 German physicist W. Heisenberg came to the conclusion that it is impossible to simultaneously, accurately measure the coordinates of a particle and its momentum, which depends on the speed, we can determine these quantities only with a certain degree of probability. In classical physics, it is assumed that the coordinates of a moving object can be determined with absolute accuracy. Quantum mechanics severely limits this possibility. W. Heisenberg in his work "Physics of the Atomic Nucleus" outlined his ideas.

W. Heisenberg's conclusion is called the principle of the uncertainty relation, which underlies the physical interpretation of quantum mechanics. Its essence is as follows: it is impossible to simultaneously have exact values ​​of different physical characteristics of a microparticle - coordinate and momentum. If we get the exact value of one quantity, then the other remains completely uncertain, there are fundamental limitations on the measurement of physical quantities that characterize the behavior of a micro-object.

Thus, W. Heisenberg concluded, reality differs depending on whether we observe it or not. "Quantum theory no longer allows a completely objective description of nature," he wrote. The measuring device influences the measurement results, i.e. in a scientific experiment, the influence of a person turns out to be irremovable. In the situation of the experiment, we are faced with the subject-object unity of the measuring device and the reality under study.

It is important to note that this circumstance is not related to the imperfection of measuring instruments, but is a consequence of the objective, corpuscular-wave properties of micro-objects. As the physicist M. Born stated, waves and particles are only "projections" of physical reality onto the experimental situation.

Two fundamental principles of quantum physics - the principle of the uncertainty relation and the principle of complementarity - indicate that science refuses to describe only dynamic laws. The laws of quantum physics are statistical. As V. Heisenberg writes, “in experiments with atomic processes, we are dealing with things and facts that are as real as any phenomena of everyday life are real. But atoms or elementary particles are not real to that extent. They rather form a world of tendencies or possibilities than the world of things and facts." Subsequently, quantum theory became the basis for nuclear physics, and in 1928. P. Dirac laid the foundations of relativistic quantum mechanics.

3. Mechanics. Mainth laws of classical mechanics

natural science science mechanics quantum

Classical mechanics is a physical theory that establishes the laws of motion of macroscopic bodies with velocities much less than the speed of light in vacuum.

Classical mechanics is subdivided into:

Statics (which considers the equilibrium of bodies)

Kinematics (which studies the geometric property of motion without considering its causes)

Dynamics (which considers the movement of bodies).

Newton's three laws form the basis of classical mechanics:

Newton's first law postulates the existence of special frames of reference, called intercial ones, in which any body maintains a state of rest or uniform rectilinear motion until forces from other bodies act on it (the law of inertia).

Newton's second law states that in inertial reference frames, the acceleration of any body is proportional to the sum of the forces acting on it and inversely proportional to the body's mass (F = ma).

Newton's third law states that when any two bodies interact, they experience forces from each other that are equal in magnitude and opposite in direction (action is equal to reaction).

In order to calculate the motion of physical bodies on the basis of these basic laws of Newtonian mechanics, they must be supplemented with a description of the forces that arise between bodies in various ways of interaction. In modern physics, many different forces are considered: gravity, friction, pressure, tension, Archimedes, lift, Coulomb (electrostatic), Lorentz (magnetic), etc. All these forces depend on the relative position and speed of interacting bodies.

Classical mechanics is a kind of mechanics (a branch of physics that studies the laws of change in the positions of bodies and the causes that cause it), based on Newton's 3 laws and Galileo's principle of relativity. Therefore, it is often called "Newtonian mechanics". An important place in classical mechanics is occupied by the existence of inertial systems. Classical mechanics is divided into statics (which considers the equilibrium of bodies) and dynamics (which considers the movement of bodies). Classical mechanics gives very accurate results within everyday experience. But for systems moving at high speeds approaching the speed of light, relativistic mechanics gives more accurate results, for systems of microscopic dimensions - quantum mechanics, and for systems with both characteristics - quantum field theory. Nevertheless, classical mechanics retains its value because it is much easier to understand and use than other theories, and in a wide range it approximates reality quite well. Classical mechanics can be used to describe the motion of objects such as tops and baseballs, many astronomical objects (such as planets and galaxies), and even many microscopic objects such as organic molecules. Although classical mechanics is broadly compatible with other "classical theories" such as classical electrodynamics and thermodynamics, inconsistencies were found in the late 19th century that could only be resolved within more modern physical theories. In particular, classical electrodynamics predicts that the speed of light is constant for all observers, which is difficult to reconcile with classical mechanics, and which led to the creation of a special theory of relativity. When considered together with classical thermodynamics, classical mechanics leads to the Gibbs paradox in which it is impossible to accurately determine the amount of entropy and to the ultraviolet catastrophe in which a blackbody must radiate an infinite amount of energy. Attempts to solve these problems led to the development of quantum mechanics.

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