The periodic law and the periodic system of chemical elements of D. I. Mendeleev based on ideas about the structure of the atom.
1. formulation of the periodic law
D.I. Mendeleev in the light of the theory of atomic structure.
The discovery of the periodic law and the development of the periodic system of chemical elements by D. I. Mendeleev were the pinnacle of the development of chemistry in the 19th century. A vast amount of knowledge about the properties of 63 elements known at that time was brought into order.
D.I. Mendeleev believed that the main characteristic of elements is their atomic weights, and in 1869 he first formulated the periodic law.
The properties of simple bodies, as well as the forms and properties of compounds of elements, are periodically dependent on the atomic weights of the elements.
Mendeleev divided the entire series of elements, arranged in order of increasing atomic masses, into periods, within which the properties of the elements change sequentially, placing the periods so as to highlight similar elements.
However, despite the enormous significance of such a conclusion, the periodic law and Mendeleev’s system represented only a brilliant generalization of facts, and their physical meaning remained unclear for a long time. Only as a result of the development of physics of the 20th century - the discovery of the electron, radioactivity, the development of the theory of atomic structure - the young, talented English physicist G. Mosle established that the magnitude of the charges of atomic nuclei consistently increases from element to element by one. With this discovery, Mosle confirmed the brilliant guess of Mendeleev, who in three places of the periodic table moved away from the increasing sequence of atomic weights.
Thus, when compiling it, Mendeleev placed 27 Co in front of 28 Ni, 52 Ti in front of 5 J, 18 Ar in front of 19 K, despite the fact that this contradicted the formulation of the periodic law, that is, the arrangement of elements in order of increasing atomic weights.
According to Mosle's law, the charges of nuclei of these elements corresponded to their position in the table.
In connection with the discovery of Mosle's law, the modern formulation of the periodic law is as follows:
the properties of elements, as well as the forms and properties of their compounds, are periodically dependent on the charge of the nucleus of their atoms.
The connection between the periodic law and the periodic system and the structure of atoms.
So, the main characteristic of an atom is not the atomic mass, but the magnitude of the positive charge of the nucleus. This is a more general accurate characteristic of an atom, and therefore an element. All properties of the Element and its position in the periodic table depend on the magnitude of the positive charge of the atomic nucleus. Thus, The serial number of a chemical element numerically coincides with the charge of the nucleus of its atom. The periodic table of elements is a graphic representation of the periodic law and reflects the structure of the atoms of the elements.
The theory of atomic structure explains the periodic changes in the properties of elements. An increase in the positive charge of atomic nuclei from 1 to 110 leads to a periodic repetition of the structural elements of the external energy level in atoms. And since the properties of elements mainly depend on the number of electrons at the outer level; then they repeat periodically. This is the physical meaning of the periodic law.
As an example, consider the change in properties of the first and last elements of periods. Each period in the periodic system begins with elements of atoms, which at the outer level have one s-electron (incomplete outer levels) and therefore exhibit similar properties - they easily give up valence electrons, which determines their metallic character. These are alkali metals - Li, Na, K, Rb, Cs.
The period ends with elements whose atoms at the outer level contain 2 (s 2) electrons (in the first period) or 8 (s 1 p 6) electrons (in all subsequent ones), that is, they have a completed external level. These are noble gases He, Ne, Ar, Kr, Xe, which have inert properties.
It is precisely because of the similarity in the structure of the external energy level that their physical and chemical properties are similar.
In each period, with an increase in the ordinal number of the elements, the metallic properties gradually weaken and non-metallic properties increase, and the period ends with an inert gas. In each period, with an increase in the ordinal number of the elements, the metallic properties gradually weaken and non-metallic properties increase, and the period ends with an inert gas.
In the light of the doctrine of the structure of the atom, the division of all elements into seven periods made by D. I. Mendeleev becomes clear. The period number corresponds to the number of energy levels of the atom, that is, the position of elements in the periodic table is determined by the structure of their atoms. Depending on which sublevel is filled with electrons, all elements are divided into four types.
1. s-elements. The s-sublayer of the outer layer (s 1 - s 2) is filled. This includes the first two elements of each period.
2. p-elements. The p-sublevel of the external level is filled (p 1 -- p 6) - This includes the last six elements of each period, starting from the second.
3. d-elements. The d-sublevel of the last level (d1 - d 10) is filled, and 1 or 2 electrons remain at the last (outer) level. These include elements of plug-in decades (10) of large periods, starting from the 4th, located between the s- and p-elements (they are also called transition elements).
4. f-elements. The f-sublevel of the deep (one third of it outside) level is filled (f 1 -f 14), and the structure of the external electronic level remains unchanged. These are lanthanides and actinides, located in the sixth and seventh periods.
Thus, the number of elements in periods (2-8-18-32) corresponds to the maximum possible number of electrons at the corresponding energy levels: in the first - two, in the second - eight, in the third - eighteen, and in the fourth - thirty-two electrons. The division of groups into subgroups (main and secondary) is based on the difference in the filling of energy levels with electrons. The main subgroup consists s- and p-elements, and a secondary subgroup - d-elements. Each group combines elements whose atoms have a similar structure of the external energy level. In this case, the atoms of the elements of the main subgroups contain at the outer (last) levels a number of electrons equal to the group number. These are the so-called valence electrons.
For elements of side subgroups, the valence electrons are not only the outer ones, but also the penultimate (second outer) levels, which is the main difference in the properties of the elements of the main and side subgroups.
It follows that the group number usually indicates the number of electrons that can participate in the formation of chemical bonds. This is physical meaning of the group number.
From the standpoint of the theory of atomic structure, the increase in the metallic properties of elements in each group with increasing charge of the atomic nucleus is easily explained. Comparing, for example, the distribution of electrons by levels in atoms 9 F (1s 2 2s 2 2р 5) and 53J (1s 2 2s 2 2р 6 3s 2 Зр 6 3d 10 4s 2 4 p 6 4d 10 5s 2 5p 5) it can be noted that they have 7 electrons in the outer level, which indicates similar properties. However, the outer electrons in an iodine atom are further away from the nucleus and are therefore less tightly held. For this reason, iodine atoms can donate electrons or, in other words, exhibit metallic properties, which is not typical for fluorine.
So, the structure of atoms determines two patterns:
a) change in the properties of elements horizontally - in a period, from left to right, metallic properties are weakened and non-metallic properties are enhanced;
b) change in the properties of elements vertically - in a group, with increasing serial number, metallic properties increase and non-metallic properties weaken.
Thus: As the charge of the nucleus of atoms of chemical elements increases, the structure of their electronic shells periodically changes, which is the reason for the periodic change in their properties.
3. Structure periodic Systems of D. I. Mendeleev.
The periodic system of D.I. Mendeleev is divided into seven periods - horizontal sequences of elements arranged in increasing order of atomic number, and eight groups - sequences of elements with the same type of electronic configuration of atoms and similar chemical properties.
The first three periods are called small, the rest - large. The first period includes two elements, the second and third periods - eight each, the fourth and fifth - eighteen each, the sixth - thirty-two, the seventh (incomplete) - twenty-one elements.
Each period (except the first) begins with an alkali metal and ends with a noble gas.
Elements of periods 2 and 3 are called typical.
Small periods consist of one row, large ones - of two rows: even (upper) and odd (lower). Metals are located in even rows of large periods, and the properties of the elements change slightly from left to right. In odd rows of large periods, the properties of the elements change from left to right, as in the elements of periods 2 and 3.
In the periodic system, for each element its symbol and serial number, the name of the element and its relative atomic mass are indicated. The coordinates of the element's position in the system are the period number and the group number.
Elements with serial numbers 58-71, called lanthanides, and elements with numbers 90-103 - actinides - are placed separately at the bottom of the table.
Groups of elements, designated by Roman numerals, are divided into main and secondary subgroups. The main subgroups contain 5 elements (or more). The secondary subgroups include elements of periods starting from the fourth.
The chemical properties of elements are determined by the structure of their atom, or rather the structure of the electron shell of the atoms. Comparison of the structure of electronic shells with the position of elements in the periodic table allows us to establish a number of important patterns:
1. The period number is equal to the total number of energy levels filled with electrons in the atoms of a given element.
2. In small periods and odd series of large periods, as the positive charge of the nuclei increases, the number of electrons in the external energy level increases. This is associated with the weakening of metallic and strengthening of non-metallic properties of elements from left to right.
The group number indicates the number of electrons that can participate in the formation of chemical bonds (valence electrons).
In subgroups, as the positive charge of the nuclei of elemental atoms increases, their metallic properties become stronger and their non-metallic properties weaken.
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On January 31, 1865, Mendeleev defended his dissertation on the topic of combining alcohol with water. Since then, he has been considered the “father” of Russian vodka. But this is not so - the scientist’s scientific work had nothing to do with alcoholic beverages
2014-01-31 08:36
They tell everything about the great Russian scientist Dmitry Ivanovich Mendeleev: the fact that he first saw his famous table in a dream, and the fact that it was he who made vodka with a strength of 40 degrees. But all this, it turns out, is nothing more than myths.
Myth one. Mendeleev Fortress
Many people think that it was Dmitry Ivanovich who set the standard for Russian vodka at 40 degrees. As if in his doctoral dissertation “Discourse on the combination of alcohol with water” it was said that such a ratio is least harmful to human health. The stand at the Vodka Museum in St. Petersburg states that Mendeleev considered the ideal strength of vodka to be 38 degrees, but this number was rounded to 40 to simplify the calculation of the alcohol tax. Moreover, this myth is widely used for advertising purposes - for example, on the labels they sometimes write that this vodka meets the standard of Russian vodka of the highest quality, approved by the tsarist government commission headed by D.I. Mendeleev in 1894. However, this is all a real... myth.
Firstly, in Mendeleev’s dissertation there is not a word about working with an alcohol solution of forty degrees concentration; the scientist explored areas of higher alcohol concentrations - from 70 degrees and above. Moreover, of Dmitry Ivanovich’s published works, there is not a single one that deals specifically with how optimally alcohol should be diluted when making vodka. Secondly, the “forty-degree standard” was established in Russia in 1843, when Mendeleev was only... nine years old, and this was done by the then government without the participation of any scientists or excise commissions.
And this standard was set for this reason: in those days, the excise tax on alcoholic beverages was taken from each degree. Consequently, the strength of the drink in each case had to be measured individually, and the measurement scale was extremely inaccurate. In addition, it turned out that on the way from the manufacturer to consumers during retail trade, vodka tended to reduce its strength: speculators simply diluted it and sold it at the price undiluted.
To stop this, and also to facilitate the procedure for collecting excise taxes, the government issued a decree according to which vodka had to be supplied to the consumer exclusively at 40 degrees. Otherwise, the participants in the process faced criminal liability.
Well, as for the very commission that, headed by Mendeleev, approved the “necessary fortress”, in reality it was formed at the suggestion of S.Yu. Witte not in 1894, but in 1895. Moreover, Mendeleev spoke at its meetings at the very end of the year, and only on the issue of excise taxes, and did not say a word about the “forty-degree standard.” The year 1894 appeared on the label, apparently from an article by historian William Pokhlebkin, who wrote that “30 years after writing his dissertation, the great chemist agrees to join the commission”. PR people added 30 years to the year the dissertation was written, and the result was 1894.
Myth two. Table in a dream
Everyone has come across the periodic table in life, at least in school classes. And almost everyone remembers that the brilliant Russian scientist first saw the table in a dream, and then drew it in reality.
The full version of this story looks like this. At the beginning of 1869, Dmitry Ivanovich was close to discovering one of the fundamental laws of nature - the periodic law of chemical elements. However, at the last stage of his work, things completely went wrong for him - he was unable to place the known chemical elements so that they would reflect the change in their properties due to an increase in atomic weight.
At some point, the exhausted scientist fell asleep right at his desk and... saw in his dream the very table that he could not compile in reality. Waking up, Mendeleev quickly drew it, then analyzed this diagram and realized that this was exactly what he had been trying to create for three days.
This story can be read in many reference books and magazines, including those devoted to the history of science, and also heard from school and college chemistry teachers. And many do not suspect that this is just a beautiful fairy tale. Mendeleev himself never mentioned such a dream either in his diary or in letters to friends. There is, however, a message from his friend, the famous geologist, professor at St. Petersburg University Alexander Inostrantsev, that Dmitry Ivanovich once told him the following: “In my dream I clearly see a table where the elements are arranged as needed. I woke up, immediately wrote it down on a piece of paper and fell asleep again. Only in one place was a correction subsequently necessary.”. It is interesting that Inostrantsev often later cited this story to his students as an example of “the mental impact of increased brain function on the human mind.” Apparently, the first disseminator of this myth was Alexander Alexandrovich, as well as his students.
However, what’s interesting is that Mendeleev himself never confirmed this when communicating with representatives of the press and other scientists. Moreover, some of his statements directly refute the hypothesis that the table was created simultaneously. For example, when asked by a Petersburg Leaf reporter about how the idea of the periodic system was born, he answered: “...Not a nickel for a line! Not like you! I’ve been thinking about it for maybe twenty-five years, and you think: I was sitting there, and suddenly a nickel for a line, a nickel for a line, and it’s done...!”
Colleagues of Dmitry Ivanovich recalled that the great scientist constantly worked on the table for several years, and that there were several versions of it. By the way, Mendeleev continued to correct it even after the publication of his work on the periodic law. In addition, Mendeleev was not the first to propose such a table. In 1864, the German scientist Julius Lothar Meyer published his table containing 28 elements arranged in six columns according to their valencies.
It turns out that Mendeleev did not invent 40-proof vodka, and he did not see the table in a dream. All these are just myths that almost always accompany the research of brilliant scientists, such as Dmitry Mendeleev, undoubtedly.
A lot has been written about the services of Dmitry Ivanovich Mendeleev (1834-1907) to science and domestic industry. His name has gone down in history forever thanks to the discovery of the periodic law of chemical elements. However, this encyclopedist and public figure wrote works (over 500 in total) not only on chemistry, but also on metrology, aeronautics, meteorology, agriculture, economics, public education, etc. Dmitry Ivanovich was proud that he served Russia in three fields . He considered the first to be scientific activity, the second to be pedagogical, and the third to be “service, to the best of our ability and ability, for the benefit of the growth of Russian industry.”
One of the greatest scientists of our time, the creator of “physical economics” (that is, the economic science of real production), the American Lyndon LaRouche, considers Mendeleev’s ideas to be fundamental, although in the West they are discredited in every possible way (even Mendeleev’s periodic law is simply called the “table of elements” without indicating the name of its creator ).
Scheme of various areas of activity of D. I. MendeleevWe must keep in mind the conditions under which Mendeleev had to defend his views. The main producers of grain for export were landowners. They believed that our country, which has vast territories under cultivation, was destined by its very destiny to be the breadwinner of Europe, where the population is dense and land is scarce. They say that efforts should be made to expand the export of agricultural products, while the necessary industrial products can be purchased abroad using the foreign currency received (except for what is absolutely necessary to equip the armed forces). Therefore, the ideas of Mendeleev, who acted as an ardent champion of the industrial development of Russia, and with the support of the broadest strata of the people, met with sharp opposition, and not only from large landowners. The scientist advocated for the formation of the entire national economic complex necessary for a modern powerful state, and tirelessly emphasized: we must talk not just about the development of industry, but about “whether it will be national or foreign.” It is not surprising, therefore, that Mendeleev’s ideological opponents were, first of all, the heads of the powerful clans of the Nobels, Rothschilds and Rockefellers, their Russian agents of influence, the pro-Western intelligentsia, including the “cream” of the scientific world, who envied the titan of science. Of course, other domestic entrepreneurs, guided by selfish interests, and corrupt officials were not delighted with such bold proposals.
In 1860, Mendeleev carefully examined the Baku fields and oil refining installations, but did not limit himself to this, but outlined a whole program to improve the efficiency of the industry. Among other things, he proposed building the Baku-Batumi pipeline and refineries on the Black Sea coast in order not only to rid Russia of the import of American kerosene, but also to export oil products to Europe.
Mendeleev opposed the tax farming system, since tax farmers were most opposed to deep processing. Later (in 1876) he visited the USA and, having become acquainted with the practice of oil production in Pennsylvania, came to the conclusion that in Russia it could be done no worse, but better. The scientist defined the future prospects for the industry as follows: “We could flood the whole world with oil.” Finance Minister Mikhail Reitern called this forecast "professor's dreams." However, it was the scientist, not the official, who was right. It was Mendeleev’s works that gave a powerful impetus to the development of theory and practice, the rational organization of the entire oil business in the country.
Manual oil extraction in the Baku fields (XIX century)The scientist considered it barbaric that raw materials from which so many valuable products could be obtained were burned in furnaces. The phrase was heard throughout the world: “Oil is not fuel, you can heat it with banknotes.”
Mendeleev saw the defects of the then practice of industrialization of the country. Thus, widespread construction of railways was launched without creating a proper metallurgical base. Rails and rolling stock had to be purchased for gold in the West. “If, along with the construction of roads, proper measures had been taken to establish iron production... Russia would have long ago sold abroad a lot of goods of this kind and the people would have used the cheapest metal tools,” the scientist noted bitterly. He comes to the conclusion: German industry was partly built with our money, and subsequently more than half of Russian factories belonged to foreigners, which, in his opinion, was dangerous both in peacetime and especially in wartime.
Mendeleev calculated the cost of supplying St. Petersburg and Moscow with Polish (from Silesia) and imported English coal, and determined under what conditions Donetsk anthracite would be competitive. He developed proposals for changing customs tariffs and justified the need to build a special coal railway ( Moscow - Donbass, was built in the 1930s.- M.A.), carrying out locking and dredging work on the Donets and Don, developing ports on the coasts of the Azov and Black Seas. When carrying out the measures he planned, Russia could not only refuse to import coal, but also export it itself, first to the Mediterranean, and then to the Baltic countries. Moreover, this task was viewed as not only economic, but also political, as a matter of the prestige of our country. According to Mendeleev, the people of the Mediterranean and Baltic countries, seeing that Russia supplies good coal, would be convinced that it is able to produce and export other high-quality goods.
Not limiting himself to studying the Donbass, Mendeleev drew the attention of the public and industrial circles to deposits in the east. He was the first to raise the question of fundamentally new methods of mining and using coal, in particular, the possibility of its underground gasification. Mendeleev considered fuel economy a very important task. He already wrote then about the need to use alternative energy sources: the sun, wind, sea tides, the internal heat of the Earth, the temperature difference between water layers in the ocean.
At that time, industrialists themselves, and even more so economists, considered such a development normal when light industry was first created, which did not require large investments. Its products - consumer goods - sell out quickly, therefore, the invested capital soon pays off. And only when substantial funds have been accumulated thanks to light industry, will it be possible to build metallurgical and machine-building plants. Mendeleev resolutely opposed such a formulation of the issue, in which, in his opinion, Russia was doomed to the position of a raw material appendage of the West. No, it is necessary to begin industrialization precisely with the creation of heavy industry, and, moreover, on the basis of the most advanced technology, with the task (as it was formulated after the revolution) to “catch up and overtake”, or rather, “bypass without catching up” the most developed in this regard countries. Mendeleev foresaw that Russia would have to compete not with any European power, but with the United States. In order for the country to become the richest and strongest in the world in 20 years, it was necessary to invest 700 million rubles annually in industrial development, twice the level reached then. At the same time, the country’s industrial potential cannot be based only on the factories of the center and a few other centers of industry in the European part of the country - a powerful shift of industry is needed to the East, to Siberia, access to the shores of the Pacific Ocean, to Sakhalin. In 1899, Mendeleev, accompanied by specialists in various industries mining goes to the Urals. This trip not only helped solve the problem of boosting industry in the region, but gave the scientist another reason to be confident in the future of Russia. Mendeleev defined the immediate prospects for the development of ferrous metallurgy in the Urals as follows: 300 million pounds per year can be produced using charcoal alone. And in order to reduce the cost of metal, it is necessary to build factories with new technology, based “primarily on independent scientific development, and not on imitation of models.” Enterprises need to be provided with new personnel. There is a need to create a “special higher polytechnic school” in the Urals, teaching mainly metallurgical sciences.
Mendeleev’s work “The Explanatory Tariff”, which contemporaries called “the bible of Russian protectionism,” caused a great resonance. The scientist proposed establishing duties on imported and exported goods, taking into account their impact on the development of Russia’s productive forces, promoting the growth of gross product or counteracting it. If, for example, some imported product does not enter our country at all, but its domestic production develops, then there will be no customs income, but the treasury will receive much more in the form of taxes from Russian enterprises. Approved by Alexander III, these proposals played an important role in protecting the young Russian industry from unfair foreign competition, when foreign capital resorted to selling goods to us at dumping prices in order to conquer the market, and after achieving this goal, inflated them above world prices.
To make it easier to overcome the numerous obstacles standing in the way of Russia's industrialization, especially those generated by the inconsistency of the interests of the treasury and private owners, Mendeleev proposed creating a fundamentally new body for state management of the economy - the Ministry of Industry. It would not represent an ordinary link in the bureaucratic apparatus, but would combine government and social principles and therefore find solutions so that “industrial business would be carried out in the common interest of the state, capitalists, workers and consumers... so that there would be no room for the arbitrariness of administrative persons... so that could not take root here... (as it happened in Western Europe) the ulcer of hostility between the interests of knowledge, capital and work.” Mendeleev also proposes to create several Russian banks to encourage the most important industries for the country, to practice the formation of partnerships more widely, etc. Standing for evolution and invariably emphasizing his loyalty to the autocracy, Mendeleev called on the tsar and the government to break the “narrow and self-interested” interests of factory owners who resist true rationalization production, expressed the hope that in the near future mineral reserves will become public, state property, and there will be no super-rich people and no poor people.
G. Colpey Medal, which was awarded to D. I. Mendeleev by the Royal Society of London in 1905The idea of the need for a harmonious combination of large and small enterprises, which found wide recognition in the West only in the third quarter of the twentieth century, was expressed by Mendeleev more than a hundred years ago. He was often considered a dreamer, an armchair thinker, as a professor should be. And he put forward one practical project after another, and over time the scientist himself or his followers could note with satisfaction: Mendeleev was not mistaken.
Mendeleev approached projects for the reorganization of social relations with the same strict standards of science and practicality. In his opinion, there are three ways to fight capitalism, greedy for big profits, “and all of them, more or less, already have application in practice... We will call these three methods: share capital, state-monopoly enterprises and artel-cooperative enterprises.. Ideally, one can imagine factories and factories based on pooled capital received from the workers and consumers themselves, operating in the same or other factories and factories" ( so-called people's enterprises are now widespread in the West.- M.A.)
Mendeleev’s proposal surprisingly resonates with our day: to transfer unprofitable enterprises “with proper control to the artel-cooperative economy, and not to close them, as is done in Western Europe, dooming workers to unemployment.” But this must be done “openly and competitively.”
Equally modern is the proposal for workers to share in profits. Mendeleev loved enterprising people, connecting with them the main hope for Russia’s breakthrough into the future, and he saw the ideal in an enterprise where the owner was a participant in all aspects of its activities, knew every employee and everyone would be interested in the overall results.
Recalling the names of domestic scientists, engineers and inventors who made discoveries of world significance and created perfect samples of technology, Mendeleev expresses confidence that a stage will come “in which our own Polzunovs, Petrovs, Schillings, Yablochkovs, Lodygins will not disappear, but will become the head of the Russian and worldwide industrial success." And descendants will see the Nizhny Novgorod Fair as a World Exhibition that will show the whole planet the power of our genius. To do this, it is necessary to open the road to the heights of education for Russian people from all classes and estates. And Mendeleev wrote popular works on economics, developed a project for a fundamentally new educational institution, and drew up cost estimates for its construction and maintenance.
Mendeleev made a prophetic prediction of the path of future development of economic science. He was one of the first to realize that in production not only cost and monetary indicators are important, but also physical indicators (for example, in agriculture it is necessary to maintain an optimal ratio of arable land, meadows and forest areas, as well as livestock and the productivity of forage land), “and Therefore, only the political economy that comes from natural science can hope to cover the subject it examines with due completeness and understand how values are created and why national wealth is formed or disappears.” With this approach, political economy can no longer be reduced to a set of combinations of three letters (c+v+m is Marx’s formula of value), but will have to resort to a specific analysis of situations, which will require economists of a completely different type than those who worked in this field then (and, alas, today); We will need people who understand the main problems of people's life and are able to solve them correctly.
It should be noted that Mendeleev understood industry not only in a narrow sense, as the production of goods and services, but also in a broad sense, including supply, sales, trade, and transport. The scientist thought about how to create a national economy that would ensure not only welfare, but also the moral health of society. He drew attention to the difference between work and labor, which is conscious and spiritual, therefore the future belongs to it.
Mendeleev defeated all his persecutors and distorters. His contribution to our national identity was so great that soon after the death of this great scientist, the thoughts he expressed seemed to be floating in the air. When, with the establishment of Soviet power, a planned economic management system and the GOELRO program appeared in the country, industrialization began, this was not plagiarism. Mendeleev's ideas were perceived by the leading figures of the Fatherland as something self-evident.
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Our information: Mendeleev's works, amounting to approximately 200 printed sheets, are devoted to economic issues. This is a tenth of all published works of the scientist.
DI. Mendeleev on public education
He constantly pursued the idea that the school is a huge force that determines the destinies of peoples and states, and believed that without expanding public education, the very development of Russia is impossible.
In articles and speeches on the state and development of education in Russia, D. I. Mendeleev expressed the following fundamental considerations: public education is the duty of the state to the lower classes. Meanwhile, the country does not even have basic general education for the majority of the child population, especially in villages. A national plan for the development of a network of schools must be developed and a special monetary fund must be available for the implementation of this plan; The fundamental principles of the organization of public education are its universality, compulsoryness and freeness.
Mendeleev was a spontaneous materialist, a revolutionary in science, fought against scholasticism, metaphysics, ignorance and called himself a realist. Dmitry Ivanovich believed that education should be based on “life realism” instead of classicism, and was an advocate of expanding the course of natural sciences at the expense of ancient languages. In his opinion, the basis of general education should be the Russian language, mathematics and natural science. D.I. Mendeleev argued that it is necessary to teach not for personal, but for public purposes. He constantly repeated: “The scientific sowing will come up for the people’s harvest.”
Back in 1871, D.I. Mendeleev wrote that educational institutions can bring the greatest benefit only if there is continuity of education: “By this I mean the opportunity for talented students of lower schools to have an unhindered transition to higher institutions.” He formulated two principles of continuity in training and education: firstly, independence and stability of the content of education at each stage; secondly, the close relationship between primary, secondary and higher education.
D.I. Mendeleev insisted on the introduction of compulsory primary education and state funding of education. Could he have imagined that secondary education would be compulsory these days?
D.I. Mendeleev believed that education should be accessible to all classes.
DI. Mendeleev about secondary school
DI. Mendeleev believed that the main task of secondary education is the development of students’ personality, a conscious attitude towards the environment, hard work, observation, and the ability to discuss important issues. He was a supporter of a strictly thought-out plan of study in secondary school and demanded a certain system of classes and a constant schedule.
The scientist sought to expel from secondary school all manifestations of formalism, rote learning, dead languages (Latin and Greek), and inclusion of vital subjects in the curriculum. Mendeleev believed that teaching should be based on the study of the surrounding reality through experience, observation, analysis and generalization, that is, he advocated intensifying the learning process. D. I. Mendeleev emphasized that reasoning without experimental verification always leads to self-deception and illusions, to a discrepancy between words and deeds, to careerist egoism, which the state does not need at all and leads a lot of people to daydreaming and inactivity, and sometimes to disappointment and despair .
Dmitry Ivanovich’s attitude towards exams in high school is interesting. In the article “Exams” he wrote “... oral, mass exams during training should be abolished, and entrance exams should be looked at only as an inevitable necessity determined by the relationship between demand and supply.”
“...exams, especially oral ones, are always more or less a lottery...it’s time to end this”
Mendeleev was especially outraged by the assessment of teachers' work based on the exam results of their students. He emphasized that testing of teachers is, of course, necessary, but it should, first of all, be carried out when choosing teachers. Teachers should be tested not during exams, but during teaching.
D.I. Mendeleev, highly appreciating the work of the teacher, made the most serious demands on him. He believed that a candidate for a teacher position must have thorough knowledge of the methods of teaching chemistry, and proposed establishing a department of pedagogy at every university. Now every educational institution has a methodological commission on chemistry. “The true work of a teacher,” wrote Mendeleev, “is done exclusively by nerves... dry reasoning alone - even with complete conscientiousness - nothing can be done in teaching, you won’t leave a good word, the work of nerves is needed...”
Dmitry Ivanovich called teachers lamps and educators, insisted that they follow science, be directly involved in it,
because only that teacher can fruitfully influence his students, replenish their knowledge, who is himself strong in science.
D.I. Mendeleev especially emphasized the educational role of the teacher, that he must know each student, his abilities, inclinations and character in order to comprehensively develop his existing inclinations. In his personal life, a teacher should be an example for students. Trust in the teacher is the basis of all education.
“Often what is important is not the truth itself, but its illumination and the strength of the argument developed in its favor. It is also important that a brilliant scientist shares his thoughts, who told the whole world that he is capable of creating great things, finding the key to the innermost secrets of nature. In this case, Mendeleev’s position perhaps resembles that taken by the great artists Shakespeare or Tolstoy. The truths presented in their works are as old as the world, but those artistic images in which these truths are clothed will remain young forever.”
L. A. Chugaev
“A brilliant chemist, a first-class physicist, a fruitful researcher in the field of hydrodynamics, meteorology, geology, in various departments of chemical technology and other disciplines related to chemistry and physics, a deep expert in the chemical industry and industry in general, especially Russian, an original thinker in the field of the study of national economy , a statesman who, unfortunately, was not destined to become a statesman, but who saw and understood the tasks and future of Russia better than the representatives of our official government.” This assessment of Mendeleev is given by Lev Aleksandrovich Chugaev.
Dmitry Mendeleev was born on January 27 (February 8), 1834 in Tobolsk, the seventeenth and last child in the family of Ivan Pavlovich Mendeleev, who at that time held the position of director of the Tobolsk gymnasium and schools of the Tobolsk district. In the same year, Mendeleev's father went blind and soon lost his job (died in 1847). All care for the family then passed to Mendeleev’s mother, Maria Dmitrievna, née Kornilieva, a woman of outstanding intelligence and energy. She managed to simultaneously manage a small glass factory, which provided (along with a meager pension) a more than modest livelihood, and take care of the children, whom she gave an excellent education for that time. She paid a lot of attention to her youngest son, in whom she was able to discern his extraordinary abilities. However, Mendeleev did not study well at the Tobolsk gymnasium. Not all subjects were to his liking. He willingly studied only mathematics and physics. His aversion to the classical school remained throughout his life.
Maria Dmitrievna Mendeleeva died in 1850. Dmitry Ivanovich Mendeleev retained a grateful memory of her until the end of his days. This is what he wrote many years later, dedicating his essay “Study of Aqueous Solutions by Specific Gravity” to the memory of his mother: “This study is dedicated to the memory of the mother by her last child. She could grow it only with her labor, running a factory; She raised her by example, corrected her with love, and in order to give to science, she took her out of Siberia, spending her last resources and strength. Dying, she bequeathed: to avoid Latin self-delusion, to insist on work, not words, and to patiently seek divine or scientific truth, because she understood how often dialectics deceives, how much still needs to be learned, and how, with the help of science, without violence, lovingly, but prejudices and errors are firmly eliminated, and the following are achieved: protection of the acquired truth, freedom of further development, common good and internal well-being. D. Mendeleev considers his mother’s covenants sacred.”
Mendeleev found favorable soil for the development of his abilities only at the Main Pedagogical Institute in St. Petersburg. Here he met outstanding teachers who knew how to instill in the souls of their listeners a deep interest in science. Among them were the best scientific forces of that time, academicians and professors of St. Petersburg University. The very environment of the institute, with all the strictness of the regime of a closed educational institution, thanks to the small number of students, the extremely caring attitude towards them and their close connection with the professors, provided ample opportunity for the development of individual inclinations.
Mendeleev's student research related to analytical chemistry: studying the composition of the minerals orthite and pyroxene. Subsequently, he did not actually engage in chemical analysis, but always considered it as a very important tool for clarifying various research results. Meanwhile, it was the analyzes of orthite and pyroxene that became the impetus for choosing the topic of his diploma work (dissertation): “Isomorphism in connection with other relationships of crystalline form to composition.” It began with these words: “The laws of mineralogy, like other natural sciences, relate to three categories that determine the objects of the visible world - form, content and properties. The laws of forms are subject to crystallography, the laws of properties and content are governed by the laws of physics and chemistry.”
The concept of isomorphism played a significant role here. This phenomenon has been studied by Western European scientists for several decades. In Russia, Mendeleev was essentially the first in this field. The detailed review he compiled of factual data and observations and the conclusions formulated on its basis would have done credit to any scientist specially dealing with the problems of isomorphism. As Mendeleev later recalled, “the preparation of this dissertation involved me in the study of chemical relations most of all. This determined a lot." He would later call the study of isomorphism one of the “precursors” that contributed to the discovery of the Periodic Law.
After completing the course at the institute, Mendeleev worked as a teacher, first in Simferopol, then in Odessa, where he used Pirogov’s advice. In 1856, he returned to St. Petersburg, where he defended his dissertation for a master's degree in chemistry, “On Specific Volumes.” At the age of 23, he became an associate professor at St. Petersburg University, where he first taught theoretical, then organic chemistry.
In 1859, Mendeleev was sent on a two-year business trip abroad. If many of his other compatriots-chemists were sent abroad mainly “to improve education”, without having their own research programs, then Mendeleev, in contrast to them, had a clearly developed program. He went to Heidelberg, where the names of Bunsen, Kirchhoff and Kopp attracted him, and there he worked in a laboratory organized by himself, mainly studying the phenomena of capillarity and surface tension of liquids, and spent his leisure hours in the circle of young Russian scientists: S. P. Botkin, I. M. Sechenov, I. A. Vyshnegradsky, A. P. Borodin and others.
In Heidelberg, Mendeleev made a significant experimental discovery: he established the existence of an “absolute boiling point” (critical temperature), upon reaching which, under certain conditions, a liquid instantly turns into steam. Soon a similar observation was made by the Irish chemist T. Andrews. Mendeleev worked in the Heidelberg laboratory primarily as an experimental physicist, and not a chemist. He failed to solve the task - to establish “the true measure for the adhesion of liquids and find its dependence on the weight of the particles.” More precisely, he did not have time to do this - his business trip expired.
At the end of his stay in Heidelberg, Mendeleev wrote: “The main subject of my studies is physical chemistry. Newton was also convinced that the cause of chemical reactions lies in simple molecular attraction, which determines cohesion and is similar to the phenomena of mechanics. The brilliance of purely chemical discoveries has made modern chemistry a completely special science, separating it from physics and mechanics, but, undoubtedly, the time must come when chemical affinity will be considered as a mechanical phenomenon... I have chosen as my specialty those questions whose solution this time can bring closer "
This handwritten document was preserved in Mendeleev’s archive; in it, he essentially expressed his “cherished thoughts” regarding the directions of knowledge of the deep essence of chemical phenomena.
In 1861, Mendeleev returned to St. Petersburg, where he resumed lecturing on organic chemistry at the university and published works entirely devoted to organic chemistry. One of them, purely theoretical, is called “An Experience in the Theory of the Limits of Organic Compounds.” In it he develops original ideas about their limiting forms in individual homological series. Thus, Mendeleev turns out to be one of the first theorists in the field of organic chemistry in Russia. He published a textbook, remarkable for that time, “Organic Chemistry” - the first Russian textbook in which the idea that unites the entire set of organic compounds is the theory of limits, originally and comprehensively developed. The first edition quickly sold out, and the student was reprinted the following year. For his work, the scientist was awarded the Demidov Prize, the highest scientific award in Russia at that time. After some time, A. M. Butlerov characterizes it this way: “This is the only and excellent original Russian work on organic chemistry, only because it is unknown in Western Europe because a translator has not yet been found for it.”
Nevertheless, organic chemistry did not become any noticeable area of Mendeleev’s activity. In 1863, the Faculty of Physics and Mathematics of St. Petersburg University elected him as a professor in the department of technology, but due to his lack of a master’s degree in technology, he was confirmed in the position only in 1865. Before that, in 1864, Mendeleev was also elected professor of the St. Petersburg University Institute of Technology
In 1865, he defended his thesis “On compounds of alcohol with water” for the degree of Doctor of Chemistry, and in 1867 he received the department of inorganic (general) chemistry at the university, which he held for 23 years. Having started preparing lectures, he discovered that neither in Russia nor abroad there was a course in general chemistry worthy of being recommended to students. And then he decided to write it himself. This fundamental work, called “Fundamentals of Chemistry,” was published in separate issues over several years. The first issue, containing an introduction, a discussion of general issues of chemistry, and a description of the properties of hydrogen, oxygen and nitrogen, was completed relatively quickly - it appeared in the summer of 1868. But while working on the second issue, Mendeleev encountered great difficulties associated with the systematization and consistency of presentation material describing chemical elements. At first, Dmitry Ivanovich Mendeleev wanted to group all the elements he described by valence, but then he chose a different method and combined them into separate groups, based on the similarity of properties and atomic weight. Reflection on this question brought Mendeleev closely to the main discovery of his life, which was called Mendeleev's Periodic Table.
The fact that some chemical elements exhibit obvious similarities was no secret to chemists of those years. The similarities between lithium, sodium and potassium, between chlorine, bromine and iodine, or between calcium, strontium and barium were striking. In 1857, the Swedish scientist Lensen combined several “triads” by chemical similarity: ruthenium - rhodium - palladium; osmium - platinum - iridium; manganese - iron - cobalt. Even attempts have been made to compile tables of the elements. The Mendeleev library contained a book by the German chemist Gmelin, who published such a table in 1843. In 1857, the English chemist Odling proposed his own version. However, none of the proposed systems covered the entire set of known chemical elements. Although the existence of separate groups and separate families could be considered an established fact, the connection between these groups remained unclear.
Mendeleev managed to find it by arranging all the elements in order of increasing atomic mass. Establishing a periodic pattern required an enormous amount of thought from him. Having written the elements with their atomic weights and fundamental properties on separate cards, Mendeleev began to arrange them in various combinations, rearranging and changing places. The matter was complicated by the fact that many elements had not yet been discovered at that time, and the atomic weights of those already known were determined with great inaccuracies. Nevertheless, the desired pattern was soon discovered. Mendeleev himself spoke in this way about his discovery of the Periodic Law: “Having suspected the existence of a relationship between elements back in my student years, I never tired of thinking about this problem from all sides, collecting materials, comparing and contrasting figures. Finally the time came when the problem was ripe, when the solution seemed about to take shape in my head. As has always happened in my life, the premonition of an imminent resolution of the question that was tormenting me led me into an excited state. For several weeks I slept in fits and starts, trying to find that magical principle that would immediately put in order the entire pile of material accumulated over 15 years. And then one fine morning, having spent a sleepless night and despairing of finding a solution, I lay down on the sofa in the office without undressing and fell asleep. And in a dream I saw a table quite clearly. I immediately woke up and sketched out the table I saw in my dream on the first piece of paper that came to hand.”
Thus, Mendeleev himself came up with the legend that he dreamed of the periodic table in a dream, for persistent fans of science who do not understand what insight is.
Mendeleev, being a chemist, took the chemical properties of elements as the basis for his system, deciding to arrange chemically similar elements below each other, while observing the principle of increasing atomic weights. It didn't work out! Then the scientist simply took and arbitrarily changed the atomic weights of several elements (for example, he assigned uranium an atomic weight of 240 instead of the accepted 60, i.e., he quadrupled it!), rearranged cobalt and nickel, tellurium and iodine, put three empty cards, predicting the existence of three unknown elements. Having published the first version of his table in 1869, he discovered the law that “the properties of elements are periodically dependent on their atomic weight.”
This was the most important thing in Mendeleev’s discovery, which made it possible to connect together all the groups of elements that had previously seemed disparate. Mendeleev quite correctly explained the unexpected disruptions in this periodic series by the fact that not all chemical elements are known to science. In his table, he left blank cells, but predicted the atomic weight and chemical properties of the proposed elements. He also corrected a number of inaccurately determined atomic masses of elements, and further research completely confirmed his correctness.
The first, still imperfect draft of the table was reconstructed in the following years. Already in 1869, Mendeleev placed the halogens and alkali metals not in the center of the table, as before, but along its edges (as is done now). In the following years, Mendeleev corrected the atomic weights of eleven elements and changed the location of twenty. As a result, in 1871, the article “Periodic Law for Chemical Elements” appeared, in which the periodic table took on a completely modern form. The article was translated into German and copies of it were sent to many famous European chemists. But, alas, no one appreciated the importance of the discovery made. The attitude towards the Periodic Law changed only in 1875, when F. Lecocde Boisbaudran discovered a new element - gallium, the properties of which strikingly coincided with the predictions of Mendeleev (he called this still unknown element eka-aluminium). Mendeleev's new triumph was the discovery of scandium in 1879, and germanium in 1886, the properties of which also fully corresponded to Mendeleev's descriptions.
Until the end of his life, he continued to develop and improve the doctrine of periodicity. The discoveries in the 1890s of the phenomena of radioactivity and noble gases presented the periodic table with serious difficulties. The problem of placing helium, argon and their analogues in the table was successfully resolved only in 1900: they were placed in an independent zero group. Further discoveries helped link the abundance of radioelements to the structure of the system.
Mendeleev himself considered the main flaw of the Periodic Law and the periodic system to be the lack of a strict physical explanation for them. It was impossible until the model of the atom was developed. However, he firmly believed that “according to the periodic law, the future does not threaten destruction, but only promises superstructures and development” (diary entry dated July 10, 1905), and the 20th century provided many confirmations of this confidence of Mendeleev.
The ideas of the Periodic Law, which were finally formed during the work on the textbook, determined the structure of the “Fundamentals of Chemistry” (the last edition of the course with the Periodic Table attached to it was published in 1871) and gave this work amazing harmony and fundamentality. All the vast factual material accumulated by this time on various branches of chemistry was presented here for the first time in the form of a coherent scientific system. “Fundamentals of Chemistry” went through eight editions and was translated into major European languages.
While working on the publication of “Fundamentals,” Mendeleev was actively engaged in research in the field of inorganic chemistry. In particular, he wanted to find the elements he predicted in natural minerals, and also to clarify the problem of “Rare Earths,” which were extremely similar in properties and did not fit well into the table. However, such research was unlikely to be within the power of one scientist. Mendeleev could not waste his time, and at the end of 1871 he turned to a completely new topic - the study of gases.
Experiments with gases acquired a very specific character - these were purely physical studies. Mendeleev can rightfully be considered one of the largest among the few experimental physicists in Russia in the second half of the 19th century. As in Heidelberg, he was engaged in the design and manufacture of various physical instruments.
Mendeleev studied the compressibility of gases and the thermal coefficient of their expansion in a wide range of pressures. He was not able to fully carry out the planned work, however, what he managed to do became a noticeable contribution to the physics of gases.
First of all, this includes the derivation of the equation of state of an ideal gas containing the universal gas constant. It was the introduction of this quantity that played a crucial role in the development of gas physics and thermodynamics. When describing the properties of real gases, he was also not far from the truth.
The physical “component” of Mendeleev’s creativity clearly manifests itself in the 1870-1880s. Of the almost two hundred works he published during this period, at least two thirds were devoted to studies of the elasticity of gases, various issues of meteorology, in particular measuring the temperature of the upper layers of the atmosphere, clarifying the patterns of dependence of atmospheric pressure on altitude, for which he developed designs of aircraft that would allow observing temperature, pressure and humidity at high altitudes.
Mendeleev's scientific works constitute only a small part of his creative heritage. As one of the biographers rightly noted, “science and industry, agriculture, public education, social and government issues, the world of art - everything attracted his attention, and everywhere he showed his powerful individuality.”
In 1890, Mendeleev left St. Petersburg University in protest against the infringement of university autonomy and devoted all his energies to practical problems. Back in the 1860s, Dmitry Ivanovich began to deal with the problems of specific industries and entire industries, and studied the conditions for the economic development of individual regions. As the material accumulates, he proceeds to develop his own program for the socio-economic development of the country, which he sets out in numerous publications. The government involves him in the development of practical economic issues, primarily on customs tariffs.
A consistent supporter of protectionism, Mendeleev played an outstanding role in the formation and implementation of Russia's customs and tariff policy in the late 19th and early 20th centuries. With his active participation, in 1890, a draft of a new customs tariff was created, in which a protective system was consistently implemented, and in 1891, a wonderful book, “The Explanatory Tariff,” was published, which provides a commentary on this project and, at the same time, a deeply thought-out overview of Russian industry indicating its needs and future prospects. This major work became a kind of economic encyclopedia of post-reform Russia. Mendeleev himself considered it a priority and dealt with it enthusiastically. “What kind of chemist I am, I am a political economist; “The Fundamentals” [of chemistry], but the “Sensible Tariff” is a different matter,” he said. A feature of Mendeleev’s creative method was complete “immersion” in the topic of interest to him, when for some time the work was carried out continuously, often almost around the clock. As a result, he created scientific works of impressive volume in an amazingly short time.
The naval and military ministries entrusted Mendeleev (1891) with the development of the issue of smokeless gunpowder, and he (after a trip abroad) in 1892 brilliantly completed this task. The “pyrocollodium” he proposed turned out to be an excellent type of smokeless gunpowder, moreover, universal and easily adaptable to any firearm. (Subsequently, Russia purchased “Mendeleev’s” gunpowder from the Americans who acquired the patent).
In 1893, Mendeleev was appointed manager of the Main Chamber of Weights and Measures, which had just been transformed on his instructions, and remained in this post until the end of his life. There Mendeleev organized a number of works on metrology. In 1899 he made a trip to the Ural factories. The result was an extensive and highly informative monograph on the state of Ural industry.
The total volume of Mendeleev's works on economic topics amounts to hundreds of printed sheets, and the scientist himself considered his work one of the three main directions of service to the Motherland, along with work in the field of natural science and teaching. Mendeleev advocated the industrial path of development of Russia: “I have not been and will not be a manufacturer, a breeder, or a trader, but I know that without them, without giving them important and significant significance, it is impossible to think about the sustainable development of the well-being of Russia.”
His works and performances were distinguished by a bright and figurative language, an emotional and interested manner of presenting the material, i.e., by what was characteristic of the unique “Mendeleev style”, “the natural wildness of the Siberian”, which never succumbed to any gloss,” which made an indelible impression on contemporaries.
Mendeleev remained at the forefront of the struggle for the economic development of the country for many years. He had to refute accusations that his activities in promoting the ideas of industrialization were due to personal interest. In a diary entry dated July 10, 1905, the scientist also noted that he saw his task in attracting capital to industry, “without getting dirty with contact with them... Let me be judged here, as and who wants, I have nothing to repent of, for neither I did not serve capital, nor brute force, nor my wealth one iota, but only tried and, as long as I can, I will try to give a fruitful, industrially real business to my country... Science and industry - these are my dreams.”
While caring about the development of domestic industry, Mendeleev could not ignore the problems of environmental protection. Already in 1859, the 25-year-old scientist published an article “On the origin and destruction of smoke” in the first issue of the Moscow magazine “Bulletin of Industry”. The author points out the great harm that untreated exhaust gases cause: “Smoke darkens the day, penetrates into homes, dirty the facades of buildings and public monuments and causes many inconveniences and ill health.” Mendeleev calculates the theoretically required amount of air for complete combustion of fuel, analyzes the composition of various types of fuel, and the combustion process. He especially emphasizes the harmful effects of sulfur and nitrogen contained in coals. This remark of Mendeleev is especially relevant today, when in various industrial installations and in transport, in addition to coal, a lot of diesel fuel and fuel oil, which have a high sulfur content, are burned.
In 1888, Mendeleev developed a project for clearing the Don and Seversky Donets, which was discussed with representatives of the city authorities. In the 1890s, the scientist took part in the publication of the Brockhaus and Efron encyclopedic dictionary, where he published a number of articles on the topics of nature conservation and resources. In the article “Waste Water,” he examines in detail the natural treatment of wastewater, using a number of examples to show how wastewater from industrial enterprises can be purified. In the article “Waste or Residues (Technical),” Mendeleev gives many examples of useful recycling of waste, especially industrial waste. “Recycling of waste,” he writes, “generally speaking, is the transformation of useless goods into goods of valuable properties, and this constitutes one of the most important achievements of modern technology.”
The breadth of Mendeleev’s work on the conservation of natural resources is characterized by his research in the field of forestry during a trip to the Urals in 1899. Mendeleev carefully studied the growth of various varieties of trees (pine, spruce, fir, birch, larch, etc.) on a huge area of the Ural region and Tobolsk province. The scientist insisted that “the annual consumption should be equal to the annual increase, because then the descendants will have as much left as we received.”
The emergence of a powerful figure of a scientist, encyclopedist and thinker was a response to the needs of developing Russia. The creative genius of Mendeleev was in demand by time. Reflecting on the results of his many years of scientific activity and accepting the challenges of the time, Mendeleev increasingly turned to socio-economic issues, explored the patterns of the historical process, and clarified the essence and features of his contemporary era. It is noteworthy that this direction of thought is one of the characteristic intellectual traditions of Russian science.