Why is chemistry a natural science? general chemistry

As a result of studying this chapter, the student should: know

• basic concepts and specifics of the chemical picture of the world;
• the role of alchemy in the development of chemistry as a science;
• historical stages in the development of chemistry as a science;
• the leading principles of the doctrine of the composition and structure of substances;
• the main factors in the course of chemical reactions and the conditions for their control;
• basic principles of evolutionary chemistry and its role in explaining biogenesis; be able to
• reveal the role of the physics of the microworld for understanding the foundations of chemical science;
• conduct a comparative analysis of the main stages in the development of chemistry;
• argued to show the role of chemistry to explain the structural levels of the systemic organization of matter;

own

• the skills of acquiring and applying knowledge to form a chemical picture of the world;
• skills in using the conceptual apparatus of chemistry to characterize chemical processes.

Historical stages in the development of chemical science

There are many definitions of chemistry that characterize it as a science:

• about chemical elements and their compounds;
• substances, their composition and structure;
• processes of qualitative transformation of substances;
• chemical reactions, as well as the laws and regularities that these reactions obey.

Obviously, each of them reflects only one of the aspects of extensive chemical knowledge, and chemistry itself acts as a highly ordered, constantly developing system of knowledge. Here is a definition from a classic textbook: “Chemistry is the science of the transformations of substances. It studies the composition and structure of substances, the dependence of the properties of substances on their composition and structure, the conditions and ways of transformation of one substance into another.

Chemistry is the science of the transformations of substances.

The most important distinguishing feature of chemistry is that it is in many ways independently forms subject of research, creating substances that did not exist in nature. Like no other science, chemistry simultaneously acts both as a science and as a production. Since modern chemistry solves its problems at the atomic-molecular level, it is closely connected with physics, biology, as well as such sciences as geology, mineralogy, etc. The border areas between these sciences are studied by quantum chemistry, chemical physics, physical chemistry, geochemistry, biochemistry and etc.

More than 200 years ago, the great M. V. Lomonosov spoke at a public meeting of the St. Petersburg Academy of Sciences. in the report "A word about the benefits of chemistry" we read prophetic lines: “Chemistry spreads its hands wide in human affairs ... Wherever we look, wherever we look, everywhere we turn before our eyes the successes of its diligence.” Chemistry began to spread its "diligence" even in Egypt - the advanced country of the Ancient World. Such branches of production as metallurgy, ceramics, glass making, dyeing, perfumery, cosmetics reached significant development there long before our era.

Let's compare the name of the science of chemistry in different languages:

All these words contain the root "chem" or " chem”, which is consonant with the words of the ancient Greek language: “himos” or “hyumos” meant “juice”. This name is found in manuscripts containing information on medicine and pharmacy.

There are other points of view. According to Plutarch, the term "chemistry" comes from one of the ancient names of Egypt - Hemi ("drawing earth"). In its original sense, the term meant "Egyptian art". Chemistry as the science of substances and their interactions was considered in Egypt a divine science and was entirely in the hands of the priests.

One of the oldest branches of chemistry is metallurgy. For 4-3 thousand years BC. began to smelt copper from ores, and later to produce an alloy of copper and tin (bronze). In the II millennium BC. learned how to get iron from ores by raw-blowing process. For 1600 years BC. they began to use natural indigo dye for dyeing fabrics, and a little later - purple and alizarin, as well as prepare vinegar, medicines from plant materials and other products, the production of which is associated with chemical processes.

In the Arab East in the V-VI centuries. the term "alchemy" appears by adding the particle "al-" to the Greco-Egyptian "chemistry". The goal of the alchemists was to create a "philosopher's stone" capable of turning all base metals into gold. It was based on a practical order: gold

in Europe was necessary for the development of trade, and there were few known gold deposits.

Fact from the history of science

The oldest discovered chemical texts are now considered ancient Egyptian "Ebers Papyrus"(named after the German Egyptologist who found it) - a collection of recipes for the manufacture of medicines of the 16th century. BC, as well as the “Brugsch Papyrus” found in Memphis with pharmaceutical prescriptions (XIV century BC).

The prerequisites for the formation of chemistry as an independent scientific discipline were formed gradually during the 17th - the first half of the 18th century. At the same time, despite the variety of empirical material, in this science, until the discovery in 1869 of the periodic system of chemical elements by D. I. Mendeleev (1834-1907), there was no general theory that could be used to explain the accumulated actual material.

Attempts to periodize chemical knowledge were made as early as the 19th century. According to the German scientist G. Kopp - the author of a four-volume monograph "History of Chemistry"(1843-1847), the development of chemistry took place under the influence of a certain guiding idea. He identified five stages:

• the era of the accumulation of empirical knowledge without attempts to theoretically explain them (from ancient times to the 4th century AD);
• alchemical period (IV - beginning of the 16th century);
• period of iatrochemistry, i.e. "Chemistry of Healing" (second quarter of the 16th - mid-17th centuries);
• the period of creation and dominance of the first chemical theory - the theory of phlogiston (mid-17th - third quarter of the 18th century);
• period of quantitative research (last quarter of the 18th - 1840s) 1 .

However, according to modern concepts, this classification refers to those stages when chemical science has not yet been constituted as a systemic theoretical knowledge.

Domestic historians of chemistry distinguish four conceptual levels, which are based on a way to solve the central problem of chemistry as a science and as a production (Fig. 13.1).

First conceptual level - study of the structure of a chemical substance. At this level, various properties and transformations of substances were studied depending on their chemical composition.

Rice. 13.1.

It is easy to see the analogy of this concept with the physical concept of atomism. Both physicists and chemists sought to find the original basis by which it would be possible to explain the properties of all simple and complex substances. This concept was formulated quite late - in 1860, at the first International Congress of Chemists in Karlsruhe, Germany. The chemists proceeded from the fact that All substances are made up of molecules and all molecules, in turn are made up of atoms. Both atoms and molecules are in continuous motion, while atoms are the smallest, and then indivisible parts of molecules 1.

The significance of the Congress was clearly expressed by D. I. Mendeleev: G. A.), chemists of all countries accepted the beginning of the unitary system; now it would be a great inconsistency, recognizing the beginning, not recognizing its consequences.

Second conceptual level - study of the structure of chemicals, identification of a specific method of interaction of elements in the composition of specific chemicals. It was found that the properties of substances depend not only on their constituent chemical elements, but also on the relationship and interaction of these elements during a chemical reaction. So, diamond and coal have different properties precisely because of the difference in structures, although their chemical composition is similar.

Third conceptual level Chemistry is generated by the needs of increasing the productivity of chemical industries and explores the internal mechanisms and external conditions for the occurrence of chemical processes: temperature, pressure, reaction rate, etc.

Fourth conceptual level - level of evolutionary chemistry. At this level, the nature of the reagents involved in chemical reactions, the specifics of the action of catalysts, which significantly accelerate their rate, are studied in more depth. It is at this level that the process of origin is comprehended. alive matter from inert matter.

• Glinka II. L. General chemistry. 2b ed. L .: Chemistry: Leningrad branch, 1987. S. 13.
• Cit. Quoted from: Koltun M. World of Chemistry. M .: Children's literature, 1988. S. 7.
• Mendeleev D. I. Op. in 25 vols. L. - M.: Publishing House of the Academy of Sciences of the USSR, 1949. T. 15. S. 171-172.

Lesson #1

Subject: Chemistry is a natural science.

Target: give the concept of chemistry as a science; show the place of chemistry among the natural sciences; to acquaint with the history of the origin of chemistry; consider the importance of chemistry in human life; learn the rules of conduct in the chemistry classroom; to acquaint with scientific methods of knowledge in chemistry; develop the logic of thinking, the ability to observe; to cultivate interest in the subject being studied, perseverance, diligence in studying the subject.

During the classes.

IClass organization.

IIUpdating of basic knowledge.

What natural sciences do you know, study?

Why are they called natural?

IIIThe message of the topic, the objectives of the lesson, the motivation of educational activities.

After reporting the topic and purpose of the lesson, the teacher poses a problematic question.

What do you think chemistry studies? (Students express their assumptions, all of them are written on the board). Then the teacher says that during the lesson we will find out which assumptions are correct.

IIILearning new material.

Before starting our lesson, we must learn the rules of conduct in the chemistry room. Look in front of you on the wall stand on which these rules are written. Every time you enter the office, you must repeat these rules, know them and strictly follow them.

(We read aloud the rules of conduct in the chemistry room.)

Rules of conduct for students in the chemistry classroom.

You can enter the chemistry room only with the permission of the teacher

In the chemistry room you need to walk with a measured step. In no case should you move sharply, as you can overturn the equipment and reagents standing on the tables

During the experimental work in the chemistry room, it is necessary to be in a dressing gown.

When conducting experimental work, you can start work only after the permission of the teacher.

When performing experiments, work calmly, without fuss. Don't push your roommate. Remember! Accuracy is the key to success!

After completing the experiments, it is necessary to put the workplace in order and wash your hands thoroughly with soap and water.

Chemistry is a natural science, the place of chemistry among the natural sciences.

The natural sciences include physical geography, astronomy, physics, biology, ecology and others. They study the objects and phenomena of nature.

Let us consider what place chemistry occupies among other sciences. It provides them with substances, materials and modern technologies. And at the same time, he uses the achievements of mathematics, physics, biology, ecology for his own further development. Therefore, chemistry is a central, fundamental science.

The boundaries between chemistry and other natural sciences are increasingly blurred. Physical chemistry and chemical physics arose at the boundary of the study of physical and chemical phenomena. Biochemistry - biological chemistry - studies the chemical composition and structure of compounds found in living organisms.

The history of the origin of chemistry.

The science of substances and their transformations originated in Egypt, the technically most advanced country of the ancient world. Egyptian priests were the first chemists. They held many hitherto unsolved chemical secrets. For example, techniques for embalming the bodies of dead pharaohs and nobles, as well as obtaining some paints.

Such branches of production as pottery, glassmaking, dyeing, perfumery, reached significant development in Egypt long before our era. Chemistry was considered a "divine" science, was entirely in the hands of the priests and was carefully hidden by them from all the uninitiated. However, some information still penetrated beyond Egypt.

Approximately in the 7th century. AD The Arabs adopted the property and methods of work of the Egyptian priests and enriched humanity with new knowledge. The Arabs added the prefix al to the word Hemi, and the leadership in the study of substances, which became known as alchemy, passed to the Arabs. It should be noted that alchemy was not widespread in Rus', although the works of alchemists were known, and even translated into Church Slavonic. Alchemy is a medieval art of obtaining and processing various substances for practical needs. Unlike the ancient Greek philosophers, who only observed the world, and the explanation was based on assumptions and reflections, alchemists acted, experimented, making unexpected discoveries and improving the experimental methodology. Alchemists believed that metals are substances consisting of three main elements: salt - as a symbol of hardness and the ability to dissolve; sulfur - as a substance that can heat up and burn at high temperatures; mercury - as a substance capable of evaporation and possessing brilliance. In this regard, it was assumed that, for example, gold, which was a precious metal, also has exactly the same elements, which means that it can be obtained from any metal! It was believed that obtaining gold from any other metal is associated with the action of the philosopher's stone, which alchemists unsuccessfully tried to find. In addition, they believed that if you drink an elixir made from the philosopher's stone, you will gain eternal youth! But the alchemists failed to find and obtain neither the philosopher's stone nor gold from other metals.

The role of chemistry in human life.

Students list all aspects of the positive impact of chemistry on human life. The teacher helps and guides the thoughts of the students.

Teacher: But is chemistry only useful in society? What problems arise in connection with the use of chemical products?

(Students are trying to find the answer to this question as well.)

Methods of knowledge in chemistry.

A person receives knowledge about nature with the help of such an important method as observation.

Observation- this is the concentration of attention on cognizable objects in order to study them.

With the help of observation, a person accumulates information about the world around him, which he then systematizes, revealing general patterns of observation results. The next important step is to search for reasons that explain the patterns found.

In order for the observation to be fruitful, a number of conditions must be met:

clearly define the subject of observation, i.e., what the observer’s attention will be drawn to - a specific substance, its properties or the transformation of some substances into others, the conditions for the implementation of these transformations, etc.;

to formulate the purpose of the observation, the observer must know why he conducts the observation;

develop an observation plan to achieve the goal. To do this, it is better to put forward an assumption, that is, a hypothesis (from the Greek. Hypothesis - foundation, assumption) about how the observed phenomenon will occur. A hypothesis can also be put forward as a result of observation, that is, when a result is obtained that needs to be explained.

Scientific observation is different from observation in the everyday sense of the word. As a rule, scientific observation is carried out under strictly controlled conditions, and these conditions can be changed at the request of the observer. Most often, such observation is carried out in a special room - a laboratory.

Experiment- scientific reproduction of a phenomenon for the purpose of its study, testing under certain conditions.

Experiment (from lat. experimentum - experience, test) allows you to confirm or refute the hypothesis that arose during the observation, and formulate a conclusion.

Let's conduct a small experiment to study the structure of the flame.

Light a candle and carefully examine the flame. It is heterogeneous in color, has three zones. The dark zone (1) is at the bottom of the flame. She is the coldest among the others. The dark zone is bordered by the bright part of the flame (2), the temperature of which is higher than in the dark zone. However, the highest temperature is in the upper colorless part of the flame (zone 3).

To make sure that different zones of the flame have different temperatures, you can conduct such an experiment. Let's place a splinter or match in the flame so that it crosses all three zones. You will see that the splinter is charred in zones 2 and 3. This means that the temperature of the flame is the highest there.

The question arises whether the flame of an alcohol lamp or dry fuel will have the same structure as the flame of a candle? The answer to this question can be two assumptions - hypotheses: 1) the structure of the flame will be the same as the flame of a candle, because it is based on the same process - combustion; 2) the structure of the flame will be different, since it arises as a result of the combustion of various substances. In order to confirm or refute one of these hypotheses, let us turn to the experiment - we will conduct an experiment.

We investigate with the help of a match or a splinter the structure of the flame of an alcohol lamp.

Despite the differences in shape, size and even color, in both cases the flame has the same structure - the same three zones: the inner dark (coldest), the middle luminous (hot) and the outer colorless (hottest).

Therefore, on the basis of the experiment, we can conclude that the structure of any flame is the same. The practical significance of this conclusion is as follows: in order to heat any object in a flame, it must be brought into the upper, i.e., the hottest, part of the flame.

It is customary to draw up experimental data in a special laboratory journal, for which an ordinary notebook is suitable, but strictly defined entries are made in it. They note the date of the experiment, its name, the course of the experiment, which is often drawn up in the form of a table.

Try to describe an experiment on the structure of a flame in this way.

All natural sciences are experimental. And to set up an experiment, special equipment is often required. For example, in biology, optical instruments are widely used, which allow you to magnify the image of the observed object many times over: a magnifying glass, a microscope.

Physicists in the study of electrical circuits use instruments to measure voltage, current, and electrical resistance.

Scientists-geographers are armed with special instruments - from the simplest (compass, meteorological probes) to research ships, unique space orbital stations.

Chemists also use special equipment in their research. The simplest of them is, for example, a heating device already familiar to you - an alcohol lamp and various chemical utensils in which transformations of substances are carried out, that is, chemical reactions.

IV Generalization and systematization of acquired knowledge.

So what does chemistry study? (During the lesson, the teacher paid attention to the correctness or incorrectness of the children's assumptions about the subject of chemistry. And now the time has come to summarize and give the final answer. We derive the definition of chemistry).

What role does chemistry play in human life and society?

What methods of knowledge in chemistry do you now know.

What is observation? What conditions must be met in order for the observation to be effective?

What is the difference between a hypothesis and a conclusion?

What is an experiment?

What is the structure of a flame?

How should the heating be done?

V Reflection, summing up the lesson, grading.

VI Communication of homework, briefing on its implementation.

Teacher: You must:

Learn the base notes for this lesson.

Describe the experiment to study the structure of the flame using the table below.

Chemistry as a science

Chemistry- a science that studies the structure of substances and their transformations, accompanied by a change in composition and (or) structure. Modern chemistry faces three main tasks:

• Firstly, the fundamental direction in the development of chemistry is the study of the structure of matter, the development of the theory of the structure and properties of molecules and materials. It is important to establish a connection between the structure and various properties of substances and, on this basis, to construct theories of the reactivity of a substance, the kinetics and mechanism of chemical reactions and catalytic phenomena. The implementation of chemical transformations in one direction or another is determined by the composition and structure of molecules, ions, radicals, and other short-lived formations. Knowing this makes it possible to find ways to obtain new products that have qualitatively or quantitatively different properties than the existing ones.
• secondly, the implementation of a directed synthesis of new substances with desired properties. Here it is also important to find new reactions and catalysts for a more efficient synthesis of already known and commercially important compounds.
• third - analysis. This traditional problem of chemistry has taken on special significance. It is associated both with an increase in the number of chemical objects and studied properties, and with the need to determine and reduce the consequences of human impact on nature.

The chemical properties of substances are determined mainly by the state of the outer electron shells of the atoms and molecules that form substances; states of nuclei and internal electrons in chemical processes almost do not change. The object of chemical research is chemical elements and their combinations, i.e. atoms, simple (single-element) and complex (molecules, ions, radical ions, carbees, free radicals) chemical compounds, their associations (associates, clusters, solvates, clathrates, etc.), materials, etc.

Modern chemistry has reached such a level of development that there are a number of its special sections, which are independent sciences. Depending on the atomic nature of the substance under study, the types of chemical bonds between atoms, inorganic, organic and organoelement chemistry are distinguished. The object of inorganic chemistry are all chemical elements and their compounds, other substances based on them. Organic chemistry studies the properties of a vast class of compounds formed through the chemical bonds of carbon with carbon and other organogenic elements: hydrogen, nitrogen, oxygen, sulfur, chlorine, bromine, and iodine. Organoelement chemistry is at the interface between inorganic and organic chemistry. This "third" chemistry refers to compounds involving the chemical bonds of carbon with the rest of the non-organogen elements in the Periodic Table. The molecular structure, the degree of aggregation (association) of atoms in the composition of molecules and large molecules - macromolecules bring their own characteristic features to the chemical form of the motion of matter. Therefore, there are chemistry of macromolecular compounds, crystal chemistry, geochemistry, biochemistry and other sciences. They study large associations of atoms and giant polymer formations of various nature. Everywhere the central question for chemistry is the question of chemical properties. The subject of study is also the physical, physicochemical and biochemical properties of substances. Therefore, not only are their own methods intensively developed, but other sciences are also involved in the study of substances. So important components of chemistry are physical chemistry and chemical physics, which study chemical objects, processes and accompanying phenomena with the help of the calculation apparatus of physics and physical experimental methods. Today, these sciences combine a number of others: quantum chemistry, chemical thermodynamics (thermochemistry), chemical kinetics, electrochemistry, photochemistry, high-energy chemistry, computer chemistry, etc. its impact on our daily lives. There are many directions in the development of applied chemistry, designed to solve specific problems of human practical activity. Chemical science has reached such a level of development that it began to generate new industries and technologies.

Chemistry as a system of knowledge

Chemistry as a system of knowledge about substances and their transformations is contained in a stock of facts - reliably established and verified information about chemical elements and compounds, their reactions and behavior in natural and artificial environments. Criteria for the reliability of facts and ways to systematize them are constantly evolving. Large generalizations that reliably connect large sets of facts become scientific laws, the formulation of which opens up new stages in chemistry (for example, the laws of conservation of mass and energy, Dalton's laws, Mendeleev's periodic law). Theories, using specific concepts, explain and predict the facts of a more particular subject area. In fact, experiential knowledge becomes a fact only when it receives a theoretical interpretation. So, the first chemical theory - the theory of phlogiston, being incorrect, contributed to the formation of chemistry, because. connected facts into a system and allowed the formulation of new questions. Structural theory (Butlerov, Kekule) streamlined and explained the vast material of organic chemistry and led to the rapid development of chemical synthesis and the study of the structure of organic compounds.

Chemistry as knowledge is a very dynamic system. The evolutionary accumulation of knowledge is interrupted by revolutions - a deep restructuring of the system of facts, theories and methods, with the emergence of a new set of concepts or even a new style of thinking. Thus, the revolution was caused by the works of Lavoisier (the materialistic theory of oxidation, the introduction of quantities, experimental methods, the development of chemical nomenclature), the discovery of Mendeleev's periodic law, the creation of new analytical methods at the beginning of the 20th century (microanalysis, chromatography). The emergence of new areas that develop a new vision of the subject of chemistry and influence all its areas (for example, the emergence of physical chemistry based on chemical thermodynamics and chemical kinetics) can also be considered a revolution.

Chemistry as an academic discipline

Chemistry is a general theoretical discipline. It is designed to give students a modern scientific understanding of matter as one of the types of moving matter, about the ways, mechanisms and methods of transforming one substance into another. Knowledge of the basic chemical laws, knowledge of the technique of chemical calculations, understanding of the opportunities provided by chemistry with the help of other specialists working in its individual and narrow areas, significantly accelerate the receipt of the desired result in various fields of engineering and scientific activity. Chemistry acquaints the future specialist with specific manifestations of a substance, makes it possible to “feel” a substance with the help of a laboratory experiment, to learn its new types and properties. A feature of chemistry as a discipline for students of non-chemical specialties is that in a small course it is necessary to have information from almost all branches of chemistry that have taken shape as independent sciences and are studied by chemists and chemist-technologists in special disciplines. In addition, the diversity of interests of representatives of different specialties often leads to the creation of specialized courses in chemistry. With all the positive aspects of such an orientation, there is also a serious drawback - the specialist's worldview narrows, the freedom of his orientation in the properties of the substance and the methods of its production and application decreases. Therefore, a chemistry course for future specialists not in the field of chemistry and chemical technology should be broad enough and, to the extent necessary, thorough to give a holistic view of the possibilities of chemistry as a science, as a branch of industry, as the basis for scientific and technological progress. The theoretical foundations for understanding the diverse and complex picture of chemical phenomena are laid by general chemistry. The chemistry of elements introduces into the concrete world of substances formed by chemical elements. A modern engineer who does not have special chemical training needs to understand the properties of various types of materials, compositions and compounds. Often, in one way or another, he has to deal with fuels, oils, lubricants, detergents, binders, ceramic, structural, electrical materials, fibers, fabrics, biological objects, mineral fertilizers, and many others. Other courses may not always give a first impression of this. This gap needs to be filled. This section belongs to the most dynamically changing part of chemistry and, of course, quickly becomes obsolete. Therefore, the timely and careful selection of material here is essential for the regular renewal of the discipline. All this leads to the expediency of introducing a separate section of applied chemistry into the course of chemistry for students of non-chemical specialties.

Chemistry as a social system

Chemistry as a social system is the largest part of the entire community of scientists. The formation of a chemist as a type of scientist was influenced by the features of the object of his science and the mode of activity (chemical experiment). The difficulties of mathematical formalization of the object (in comparison with physics) and at the same time the variety of sensory manifestations (smell, color, biological and other activity) from the very beginning limited the dominance of mechanism in the thinking of the chemist and left, therefore, a field for intuition and artistry. In addition, the chemist has always used an instrument of non-mechanical nature - fire. On the other hand, unlike the biologist's stable objects given by nature, the chemist's world has an inexhaustible and rapidly growing diversity. The irremovable mystery of the new substance gave the chemist's attitude to the world responsibility and caution (as a social type, a chemist is conservative). The chemical laboratory has developed a rigid mechanism of "natural selection", rejection of presumptuous and error-prone people. This gives originality not only to the style of thinking, but also to the spiritual and moral organization of the chemist.

The community of chemists consists of people who are professionally involved in chemistry and who identify themselves with this field. Approximately half of them work, however, in other areas, providing them with chemical knowledge. In addition, many scientists and technologists adjoin them - to a large extent chemists, although they no longer consider themselves chemists (mastering the skills and abilities of a chemist by scientists in other areas is difficult due to the above features of the subject).

Like any other close-knit community, chemists have their own professional language, system of personnel reproduction, communication system [journals, congresses, etc.], their own history, their own cultural norms and style of behavior.

Chemistry as an industry

The modern standard of living of mankind is simply impossible without the products and methods of chemistry. They decisively determine the modern face of the world around us. So many products of chemistry are required that in developed countries there are chemical industries. The chemical industry is one of the most important industries in our country. The chemical compounds produced by it, various compositions and materials are used everywhere: in mechanical engineering, metallurgy, agriculture, construction, electrical and electronic industries, communications, transport, space technology, medicine, everyday life, etc. About a thousand different chemical compounds, and in total for practical needs the industry produces more than a million substances. The economic well-being and defense capability of the country largely depends on chemistry. Therefore, in order not to hinder the development of other industries and to provide them with new compounds and materials with the required set of properties in a timely manner, chemical science and the chemical industry must develop at a faster pace, expanding the range of products, improving their quality and increasing production volumes. In our country there are:

• inorganic production of basic chemistry, producing acids, alkalis, salts and other compounds, fertilizers;
• petrochemical production: production of fuel, oils, solvents, monomers of organic chemistry (hydrocarbons, alcohols, aldehydes, acids), various polymers and materials based on them, synthetic rubber, chemical fibers, plant protection products, feed and feed additives, household goods chemistry;
• small chemistry, when the volumes of products produced are small, but its range is very wide. Such products include auxiliaries for the production of polymeric materials (catalysts, stabilizers, plasticizers, flame retardants), dyes, drugs, disinfectants and other sanitation and hygiene products, agricultural chemicals - herbicides, insecticides, fungicides, defoliants, etc.

The main directions of development of the modern chemical industry are: the production of new compounds and materials and increasing the efficiency of existing industries. To do this, it is important to find new reactions and catalysts, to elucidate the mechanisms of ongoing processes. This determines the chemical approach in solving engineering problems of increasing production efficiency. A typical feature of the chemical industry is a relatively small number of employees and high requirements for their qualifications, and the relative number of chemical specialists is small, and there are more representatives of other specialties (mechanics, heat power engineers, specialists in production automation, etc.). Characterized by large amounts of energy and water consumption, high environmental requirements for production. In non-chemical industries, many technological operations are associated with the preparation and cleaning of raw materials and materials, painting, gluing, and other chemical processes.

Chemistry is the basis of scientific and technological progress

Compounds, compositions and materials created by chemistry play a crucial role in increasing labor productivity, reducing energy costs for the production of necessary products, and mastering new technologies and equipment. There are many examples of the successful influence of chemistry on the methods of machine-building technology, methods of operating machines and devices, the development of the electronics industry, space technology and jet aviation, and many other areas of scientific and technological progress:

• the introduction of chemical and electrochemical methods of metal processing dramatically reduces the amount of waste that is inevitable in metal cutting. At the same time, restrictions on the strength and hardness of metals and alloys, the shape of the part are removed, high surface cleanliness and dimensional accuracy of parts are achieved.
• Materials such as synthetic graphite (which is stronger than metals at high temperatures), corundum (alumina-based) and quartz (silica-based) ceramics, synthetic polymer materials, and glass can exhibit unique properties.
• crystallized glasses (sitalls) are obtained by introducing substances into molten glass that promote the emergence of crystallization centers and the subsequent growth of crystals. Such glass-ceramic as "pyroceram" is nine times stronger than rolled glass, harder than high-carbon steel, lighter than aluminum and close to quartz in terms of heat resistance.
• modern lubricants can significantly reduce the coefficient of friction and increase the wear resistance of materials. The use of oils and lubricants containing molybdenum disulfide increases the service life of vehicle components and parts by 1.5 times, individual parts - up to two times, while the friction coefficient can be reduced by more than 5 times.
• organoelement substances - polyorganosiloxanes are characterized by flexibility and a spiral structure of molecules that form coils as the temperature decreases. Thus, they retain slightly varying viscosity over a wide temperature range. This allows them to be used as a hydraulic fluid in a wide variety of conditions.
• The protection of metals from corrosion has acquired a purposefulness of action after the creation of the electrochemical theory of corrosion and makes it possible to avoid significant economic costs for the renewal of metal products.

At present, chemistry, together with other sciences, technology and industry, faces many urgent and complex tasks. The synthesis and practical application of suitable high-temperature and, further, hot superconductors will significantly change the methods of energy storage and transmission. New materials are needed, among which metal-based materials, polymers, ceramics and composites stand out. So the problem of creating an environmentally friendly engine, which is based on the reaction of hydrogen combustion in oxygen, is to create materials or processes that prevent the penetration of hydrogen through the walls of hydrogen storage tanks. The creation of new chemical technologies is also an important area of ​​scientific and technological progress. Thus, the task is to provide new types of liquid and gaseous fuels obtained during the processing of coal, shale, peat, and wood. This is possible on the basis of new catalytic processes.

The whole diverse world around us is matter which appears in two forms: substances and fields. Substance is made up of particles that have their own mass. Field- a form of existence of matter, which is characterized by energy.

The property of matter is movement. Forms of matter movement are studied by various natural sciences: physics, chemistry, biology, etc.

It should not be assumed that there is an unambiguous strict correspondence between the sciences on the one hand, and the forms of motion of matter on the other. It must be borne in mind that in general there is no such form of motion of matter that would exist in its pure form, separately from other forms. All this emphasizes the difficulty of classifying the sciences.

X imyu can be defined as a science that studies the chemical form of the movement of matter, which is understood as a qualitative change in substances: Chemistry studies the structure, properties and transformations of substances.

TO chemical phenomena refers to phenomena in which one substance is converted into another. Chemical phenomena are otherwise known as chemical reactions. Physical phenomena are not accompanied by the transformation of one substance into another.

At the heart of every science is some set of prior beliefs, fundamental philosophies, and answers to the question about the nature of reality and human knowledge. This set of beliefs, values ​​shared by members of a given scientific community is called paradigms.

The main paradigms of modern chemistry:

1. Atomic and molecular structure of matter

2. Law of conservation of matter

3. Electronic nature of the chemical bond

4. Unambiguous relationship between the structure of matter and its chemical properties (periodic law)

Chemistry, physics, biology only at first glance may seem to be sciences far from each other. Although the laboratories of a physicist, a chemist and a biologist are very different, all these researchers deal with natural (natural) objects. This distinguishes the natural sciences from mathematics, history, economics and many other sciences that study what is not created by nature, but primarily by man himself.

Ecology is close to the natural sciences. It should not be thought that ecology is "good" chemistry, in contrast to the classical "bad" chemistry that pollutes the environment. There is no "bad" chemistry or "bad" nuclear physics - there is scientific and technological progress or its lack in some field of activity. The task of the ecologist is to use the new achievements of the natural sciences in order to minimize the risk of disturbing the habitat of living beings with the maximum benefit. The balance of "risk-benefit" is the subject of study of ecologists.

There are no strict boundaries between the natural sciences. For example, the discovery and study of the properties of new types of atoms was once considered the task of chemists. However, it turned out that of the currently known types of atoms, some were discovered by chemists, and some - by physicists. This is just one of many examples of "open boundaries" between physics and chemistry.

Life is a complex chain of chemical transformations. All living organisms absorb some substances from the environment and release others. This means that a serious biologist (botanist, zoologist, doctor) cannot do without knowledge of chemistry.

Later we will see that there is no absolutely precise boundary between physical and chemical transformations. Nature is one, so we must always remember that it is impossible to understand the structure of the world around us, delving into only one of the areas of human knowledge.

The discipline "Chemistry" is connected with other natural science disciplines by interdisciplinary connections: the previous ones - with mathematics, physics, biology, geology and other disciplines.

Modern chemistry is a branched system of many sciences: inorganic, organic, physical, analytical chemistry, electrochemistry, biochemistry, which are mastered by students in subsequent courses.

Knowledge of the course of chemistry is necessary for the successful study of other general scientific and special disciplines.

Figure 1.2.1 - The place of chemistry in the system of natural sciences

The improvement of research methods, primarily experimental technology, led to the division of science into ever narrower areas. As a result, the quantity and "quality", i.e. the reliability of information has increased. However, the impossibility for one person to have complete knowledge even for related scientific fields has created new problems. Just as in military strategy the weakest points of defense and offensive are at the junction of fronts, in science the areas that cannot be unambiguously classified remain the least developed. Among other reasons, one can also note the difficulty in obtaining the appropriate qualification level (academic degree) for scientists working in the areas of the “junction of sciences”. But the main discoveries of our time are also being made there.

Chemistry is a natural science. Chemistry in the environment. Brief information from the history of chemistry

Chemistry belongs to the natural sciences. Chemistry is the science of substances, their properties and transformations. The subject of chemistry is the chemical elements and their compounds, as well as the patterns by which chemical reactions proceed. Modern chemistry is very diverse both in terms of objects and methods of their study, therefore many of its sections are independent sciences. Now the main branches of chemistry are inorganic chemistry, organic chemistry and physical chemistry. At the same time, significant sections of chemistry arose on the border with other sciences. Thus, the interaction of chemistry and physics gave, in addition to physical chemistry, chemical physics. One of the advanced areas of chemistry is biochemistry - a science that studies the chemical foundations of life. Almost every scientific study requires the use of physical methods to establish the structure of matter and mathematical methods to analyze the results.

Chemistry plays an important role in scientific and technological progress. It has found application in all branches of science, technology and production. Chemistry ensures the processing of minerals into valuable products. Chemistry has a significant impact on the productivity of agricultural production. Equally significant is the role of chemistry in the production of plastics, paints, building materials, synthetic fabrics, synthetic detergents, perfumes and pharmaceuticals. The study of chemistry helps a person not only to increase general erudition, but also to know himself and the world around him.

The term "chemistry" first appeared in a treatise by the Egyptian Greek Zosimus in 400 AD, in which Zosimus says that "chemistry" was taught to people by demons who descended to earth from heaven. The name "chemistry" comes from the word "Khemi" or "Humana", which the ancient Egyptians called their country, as well as the Nile black soil.

The first chemists were the Egyptian priests. Significant experimental material had already been collected and described in the third century BC. In the well-known library of Alexandria, there were about seven hundred handwritten books, many works on chemistry were kept. The Greek philosopher Democritus, who lived in the fifth century BC, first suggested that all bodies are made up of small, invisible, indivisible particles of solid matter that move. He called these particles "atoms". From the third century AD, the period of alchemy began in the history of chemistry, the purpose of which was to find ways to turn base metals into noble ones (silver and gold) using the philosopher's stone. In Rus', alchemy was not widespread, although the treatises of alchemists were known. At the beginning of the sixth century, alchemists began to apply their knowledge to the needs of production and treatment. During the period of the seventeenth and eighteenth centuries, experimental methods began to be used in chemical research.

The first theory of scientific chemistry was the theory of phlogiston (a weightless substance that is released from a substance during combustion of substances), proposed by G. Stahl in the eighteenth century. This theory turned out to be erroneous, although it lasted for almost a century. The French chemist A. Lavoisier and the Russian chemist M. V. Lomonosov used precise measurements in the study of chemical reactions, refuted the theory of phlogiston, and formulated the law of conservation of mass. From 1789 to 1860, the period of quantitative chemical laws (atomic and molecular science) continued. The modern stage in the development of chemical science, which began in the twentieth century, continues to the present day. Any progress in practical chemistry today is based on the achievements of fundamental science.