Dmitri Ivanovich Mendeleev. Periodic law of D. I. Mendeleev And "Fundamentals of chemistry" Mendeleev fundamentals of chemistry 1877

The periodic law was discovered by D.I. Mendeleev in the course of work on the text of the textbook "Fundamentals of Chemistry", when he encountered difficulties in systematizing factual material. By mid-February 1869, pondering the structure of the textbook, the scientist gradually came to the conclusion that the properties of simple substances and the atomic masses of elements are connected by a certain pattern.

The discovery of the periodic table of elements was not done by chance, it was the result of tremendous work, long and painstaking work that was expended both by Dmitry Ivanovich himself and by many chemists from among his predecessors and contemporaries. “When I began to finalize my classification of elements, I wrote on separate cards each element and its compounds, and then, arranging them in the order of groups and rows, I received the first visual table of the periodic law. But this was only the final chord, the result of all the previous work ... ”- said the scientist. Mendeleev emphasized that his discovery was the result that completed twenty years of thinking about the connections between elements, thinking from all sides of the relationship of elements.

On February 17 (March 1), the manuscript of the article, containing a table entitled "Experience of a system of elements based on their atomic weight and chemical similarity," was completed and submitted to the press with notes for typesetters and with the date "February 17, 1869". The announcement of Mendeleev's discovery was made by the editor of the Russian Chemical Society, Professor N.А. Menshutkin at the meeting of the society on February 22 (March 6) 1869. Mendeleev himself was not present at the meeting, since at that time, on the instructions of the Free Economic Society, he examined the cheese dairies of the Tver and Novgorod provinces.

In the first version of the system, the elements were arranged by the scientists in nineteen horizontal rows and six vertical columns. On February 17 (March 1), the opening of the periodic law was by no means completed, but had just begun. Dmitry Ivanovich continued its development and deepening for almost three more years. In 1870, Mendeleev, in his Fundamentals of Chemistry, published the second version of the system (The Natural System of Elements): the horizontal columns of analogous elements turned into eight vertically arranged groups; the six vertical columns of the first variant turned into periods beginning with an alkali metal and ending with a halogen. Each period was divided into two rows; the elements of the different rows included in the group formed subgroups.

The essence of Mendeleev's discovery was that with an increase in the atomic mass of chemical elements, their properties change not monotonically, but periodically. After a certain number of elements of different properties, arranged in increasing atomic weight, the properties begin to repeat. The difference between the work of Mendeleev and the work of his predecessors was that Mendeleev had not one but two bases for the classification of elements - atomic mass and chemical similarity. In order for the periodicity to be fully observed, Mendeleev corrected the atomic masses of some elements, placed several elements in his system, contrary to the ideas accepted at that time about their similarity with others, left empty cells in the table where the elements that had not yet been discovered were to be located.

In 1871, on the basis of these works, Mendeleev formulated the Periodic Law, the form of which was somewhat improved over time.

The periodic table of elements had a great influence on the subsequent development of chemistry. It was not only the first natural classification of chemical elements, which showed that they form a harmonious system and are in close connection with each other, but also became a powerful tool for further research. At the time when Mendeleev compiled his table on the basis of the periodic law he discovered, many elements were not yet known. Over the next 15 years, Mendeleev's predictions were brilliantly confirmed; all three expected elements were discovered (Ga, Sc, Ge), which was the greatest triumph of the periodic law.

ARTICLE "MENDELEEV"

Mendeleev (Dmitry Ivanovich) - prof., B. in Tobolsk, January 27, 1834). His father, Ivan Pavlovich, director of the Tobolsk gymnasium, soon became blind and died. Mendeleev, a ten-year-old boy, remained in the care of his mother, Maria Dmitrievna, nee Kornilieva, a woman of outstanding intelligence and general respect in the local intelligent society. M.'s childhood and school years pass in an environment favorable for the education of an original and independent character: his mother was a supporter of the free awakening of a natural vocation. The love of reading and study was clearly expressed in M. only after the end of the gymnasium course, when the mother, deciding to send her son to science, took him as a 15-year-old boy from Siberia, first to Moscow, and then a year later to Petersburg, where she was placed in the pedagogical institute ... The institute began a real, all-consuming study of all branches of positive science ... After completing the course at the institute, due to failing health, he left for the Crimea and was appointed a gymnasium teacher, first in Simferopol, then in Odessa. But already in 1856. he again returned to St. Petersburg, entered the assistant professor in St. Petersburg. univ. and defended his thesis "On specific volumes" for a master's degree in chemistry and physics ... In 1859, M. was sent abroad ... In 1861, M. again entered as a privat-docent in St. Petersburg. university. Soon afterwards he published a course on "Organic Chemistry" and an article "On the limit of СnН2n + hydrocarbons". In 1863 M. was appointed professor of St. Petersburg. Institute of Technology and for several years he was engaged in technical issues: he traveled to the Caucasus to study oil near Baku, made agricultural experiments Imp. Free Economic Society, published technical manuals, etc. In 1865, he carried out research on alcohol solutions by their specific gravity, which was the subject of his doctoral dissertation, which he defended the following year. Professor of St. Petersburg. univ. at the Department of Chemistry M. was elected and determined in 1866.Since then, his scientific activity has assumed such dimensions and variety that in brief outline only the most important works can be pointed out. In 1868 - 1870 he writes his "Fundamentals of Chemistry", where for the first time the principle of his periodic system of elements is carried out, which made it possible to foresee the existence of new, still undiscovered elements and accurately predict the properties of both themselves and their various compounds. In 1871 - 1875. studies the elasticity and expansion of gases and publishes his essay "On the elasticity of gases." In 1876, on behalf of the government, he went to Pennsylvania to inspect American oil fields and then several times to the Caucasus to study the economic conditions of oil production and the conditions of oil production, which led to the widespread development of the oil industry in Russia; He himself is engaged in the study of petroleum hydrocarbons, publishes several works on everything and in them examines the question of the origin of oil. Around the same time, he was engaged in issues related to aeronautics and fluid resistance, accompanying his studies with the publication of individual works. In the 80s. he again turned to the study of solutions, the result of which was Op. "Investigation of aqueous solutions by specific gravity", the conclusions of which have found so many followers among chemists of all countries. In 1887, during the complete solar eclipse, one rises in a balloon in Klin, he makes a risky adjustment of the valves, makes the balloon obedient and records in the annals of this phenomenon everything that he managed to notice. In 1888 he studied the economic conditions of the Donetsk coal region on the spot. In 1890, Mr .. M. stopped reading his course in inorganic chemistry in St. Petersburg. university. From this time on, other extensive economic and state tasks began to occupy him especially. Appointed as a member of the Council of Trade and Manufactures, he takes an active part in the development and systematic implementation of a tariff that is patronizing for the Russian manufacturing industry and publishes the essay "Explanatory Tariff of 1890", which explains in all respects why Russia needed such protection. At the same time, he was involved by the military and naval ministries on the issue of rearmament of the Russian army and navy to develop a type of smokeless gunpowder, and after a trip to England and France, which already had their own gunpowder, he was appointed in 1891 as a consultant to the governing naval ministry on gunpowder issues and, working together with employees (his former students) in the scientific and technical laboratory of the naval department, opened specifically for the purpose of studying this issue, already at the very beginning of 1892 indicates the required type of smokeless powder, called pyrocollodion, universal and easily adaptable to all kinds of firearms. With the opening in the Ministry of Finance of the Chamber of Weights and Measures, in 1893, it is determined by the scientist custodian of weights and measures and begins the publication of the "Vremennik", which publishes all measuring research carried out in the Chamber. Sensitive and responsive to all scientific issues of paramount importance, M. was also keenly interested in other phenomena of current Russian social life, and wherever possible, he said his word ... etc., and in 1894 he was elected a full member of the Imperial Academy of Arts ... Of paramount importance, the various scientific issues that were the subject of M.'s study, due to their number, cannot be listed here. He has written up to 140 works, articles and books. But the time has not yet come to assess the historical significance of these works, and M., hopefully, will not stop exploring and expressing his powerful word on the newly emerging issues of both science and life for a long time ...

RUSSIAN CHEMICAL SOCIETY

The Russian Chemical Society is a scientific organization founded at St. Petersburg University in 1868 and was a voluntary association of Russian chemists.

The need to create the Society was announced at the 1st Congress of Russian Naturalists and Physicians, held in St. Petersburg at the end of December 1867 - early January 1868. At the Congress, the decision of the participants of the Chemical Section was announced:

“The Chemical Section has declared a unanimous desire to unite in the Chemical Society to communicate with the already established forces of Russian chemists. The section believes that this society will have members in all cities of Russia, and that its publication will include the works of all Russian chemists, printed in Russian. "

By this time, chemical societies had already been established in several European countries: the London Chemical Society (1841), the Chemical Society of France (1857), the German Chemical Society (1867); The American Chemical Society was founded in 1876.

The Charter of the Russian Chemical Society, drawn up mainly by D.I. Mendeleev, was approved by the Ministry of Public Education on October 26, 1868, and the first meeting of the Society took place on November 6, 1868. Initially, it included 35 chemists from St. Petersburg, Kazan, Moscow, Warsaw, Kiev, Kharkov and Odessa. In the first year of its existence, the RCS grew from 35 to 60 members and continued to grow smoothly in subsequent years (129 - in 1879, 237 - in 1889, 293 - in 1899, 364 - in 1909, 565 - in 1917).

In 1869, the Russian Chemical Society got its own organ - the Journal of the Russian Chemical Society (ZhRHO); the magazine was published 9 times a year (monthly, except for the summer months).

In 1878, the Russian Chemical Society merged with the Russian Physical Society (founded in 1872) to form the Russian Physicochemical Society. The first Presidents of the RFHO were A.M. Butlerov (in 1878-1882) and D.I. Mendeleev (in 1883-1887). In connection with the merger since 1879 (from the 11th volume), the "Journal of the Russian Chemical Society" was renamed into the "Journal of the Russian Physicochemical Society". The frequency of publication was 10 issues per year; the journal consisted of two parts - chemical (ZhRHO) and physical (ZhRFO).

For the first time, many works of the classics of Russian chemistry were published on the pages of ZhRHO. The works of D.I. Mendeleev on the creation and development of the periodic table of elements and A.M. Butlerov, connected with the development of his theory of the structure of organic compounds ... During the period from 1869 to 1930, 5067 original chemical studies were published in ZhRHO, abstracts and review articles on certain issues of chemistry, translations of the most interesting works from foreign journals were also published.

RFCO became the founder of the Mendeleev Congresses on General and Applied Chemistry; the first three congresses were held in St. Petersburg in 1907, 1911 and 1922. In 1919, the publication of ZhRFKhO was suspended and resumed only in 1924.

Fundamentals of chemistry D. Mendeleev, professor of the Imperial St. Petersburg. University. Part 1-2. SPb., Printing house of the public goods company "Public Benefit", 1869-71.
Part one: 4 [n.n.], III, 1 [n.n.], 816 pages, 151 polytypes. SPb., 1869. Mr. Nikitin stenographed from the words of the author almost the entire first part of the work. Most of the drawings were cut by Mr. Udgof. The proofs were kept by Messrs. Ditlov, Bogdanovich and Pestrechenko. The first part contains the so-called small table "Experience of a system of elements based on their atomic weight and chemical similarity" with 66 elements!
Part two: 4 [n.n.], 1 [n.n.], 951 p., 1 [n.n.], 28 polytypes. SPb., 1871. Messrs. Verigo, Marcuse, Kikin and Leontyev stenographed the second part of the work. The drawings were cut by Mr. Ugdof. The proofs of almost the entire volume were done by Mr. Demin. The second part contains the folding Natural System of Elements by D. Mendeleev and the Index of Elements. True, the number of elements increased to 96, 36 of which are vacant (they will be found and received later). In black p / c bindings of that time with gold embossing on the spines. The owner's A.Sh. Good condition. Format: 18x12 cm. On the second half of the first flyleaf, the autograph of D.I. Mendeleev: "Dear friend ... the author."

Everyone knows about the existence of the Periodic Table and the Periodic Law of Chemical Elements, the author of which is the great Russian chemist D.I. Mendeleev. In 1867, Mendeleev took the department of inorganic (general) chemistry at the Imperial St. Petersburg. University as an ordinary professor. In 1868 Mendeleev began work on "Fundamentals of Chemistry." While working on this course, he discovered the periodic law of chemical elements. According to legend, on February 17, 1869, after a long reading, he unexpectedly fell asleep on his sofa in his office and dreamed of the periodic system of elements ... based on their atomic weight and chemical similarity ”and sent this leaflet in March 1869 to many Russian and foreign chemists. The message about the relationship between the properties of elements and their atomic weights discovered by Mendeleev was made on March 6 (18), 1869 at a meeting of the Russian Chemical Society (N.A. atomic weight of elements "), 1869. In the summer of 1871, Dmitry Ivanovich summarized his research related to the establishment of the periodic law in the work" Periodic legality for chemical elements. " In 1869, not a single person in the world thought about the classification of chemical elements more than Mendeleev, and, perhaps, no chemist knew more about chemical elements than he did. He knew that the similarity of crystalline forms, manifested in isomorphism, is not always a sufficient basis for judging the similarity of elements. He knew that specific volumes also did not provide a clear guideline for classification. He knew that in general the study of cohesion, heat capacity, density, refractive indices, spectral phenomena had not yet reached a level that would make it possible to put these properties as the basis for the scientific classification of elements. But he also knew something else - that such a classification, such a system must necessarily exist. It was guessed, many scientists tried to decipher it, and Dmitry Ivanovich, who closely followed the work in the area of interest to him, could not but know about these attempts. The fact that some elements exhibit features of a completely clear similarity was not a secret for any chemist of those years. The similarities between lithium, sodium and potassium, between chlorine, bromine and iodine, or between calcium, strontium and barium were striking to anyone. And the interesting ratios of the atomic weights of such similar elements did not escape Dumas' attention. So, the atomic weight of sodium is equal to the half-sum of the weights of the neighboring lithium and potassium. The same can be said for strontium and its neighbors calcium and barium. Moreover, Dumas discovered such strange digital analogies in similar elements, which revived the attempts of the Pythagoreans to find the essence of the world in numbers and their combinations. Indeed, the atomic weight of lithium is 7, sodium is 7 + (1 x 16) = 23, potassium is 7 + (2 x 16) = 39! In 1853, the English chemist J. Gladstone drew attention to the fact that elements with close atomic weights are similar in chemical properties: such are platinum, rhodium, iridium, osmium, palladium and ruthenium or iron, cobalt, nickel. Four years later, the Swede Lensep combined several "triads" by chemical similarity: ruthenium - rhodium - palladium; osmium - platinum - iridium; manganese - iron - cobalt. The German M. Pettenkofer noted the special significance of the numbers 8 and 18, since the differences between the atomic weights of similar elements were often close to 8 and 18, or multiples of them. Attempts have even been made to compile tables of elements. In the Mendeleev's library there is a book by the German chemist L. Gmelin, in which such a table was published in 1843. In 1857, the English chemist W. Odling proposed his own version. But ... “All the observed relations in the atomic scales of analogs,” wrote Dmitry Ivanovich, “have not led, however, to any logical consequence, have not even received the right of citizenship in science due to many shortcomings. Firstly, as far as I know, not a single generalization connecting all known natural groups into one whole did not appear, and therefore the conclusions drawn for some groups suffered from fragmentary and did not lead to any further logical conclusions, seemed necessary and unexpected phenomenon ... Secondly, such facts were noticed ... where similar elements had close atomic weights. In the end, therefore, one could only say that the similarity of elements is sometimes associated with the closeness of atomic weights, and sometimes with the correct increase in their magnitude. Third, they did not even look for any exact and simple relationships in atomic weights between dissimilar elements ... " Dmitry Ivanovich brought from the first business trip abroad. And he read it carefully. This is evidenced by numerous notes in the margins, this is evidenced by the phrase noted by Dmitry Ivanovich: “The above relations between atomic weights ... of chemically similar elements, of course, can hardly be attributed to chance, but now we must leave the future to find a pattern that is visible between the indicated numbers. " These words were written in 1859, and exactly ten years later the time has come for the discovery of this pattern. “I was repeatedly asked,” recalls Mendeleev, “on what basis, based on what thought, did I find and stubbornly defend the periodic law? .. My personal thought at all times ... dwelt on the fact that we are powerless to understand in their essence or in separation that we can study them in manifestations where they are inevitably combined, and that they, in addition to their inherent eternity, have their own - comprehensible - common distinctive features or properties that should be studied in all ways ... Having devoted my energies to the study of matter, I see in it two such signs or properties: mass, occupying space and manifesting ... clearer or most real of all in weight, and personality , expressed in chemical transformations, and most clearly in the concept of chemical elements. When you think about a substance ... it is impossible, for me, to avoid two questions: how much and what substance is given, to which the concepts of mass and chemical elements correspond ... Therefore, the idea that there must be a connection between mass and chemical elements involuntarily arises , and since the mass of a substance ... is finally expressed in the form of atoms, then it is necessary to look for a functional correspondence between the individual properties of the elements and their atomic weights ... So I began to select, writing on separate cards the elements with their atomic weights and fundamental properties, similar elements and close atomic weights, which quickly led to the conclusion that the properties of the elements are periodically dependent on their atomic weight ... " to understand what lies behind the somewhat vague concept of "individuality, expressed in chemical transformations." Indeed, atomic weight is an understandable and easily expressed quantity in numbers. But how, in what numbers can one express the ability of an element to chemical reactions ? Now a person who is familiar with chemistry at least in the amount of high school will easily answer this question: the ability of an element to give certain types of chemical compounds is determined by its valence. But today it is easy to say this only because it is the periodic system that contributed to the development of the modern concept of valence. As we have already said, the concept of valence (Mendeleev called it atomicity) was introduced into chemistry by Frankland, who noticed that an atom of one or another element can bind a certain number of atoms of other elements. Let's say a chlorine atom can bond one hydrogen atom, so both of these elements are monovalent. Oxygen in a water molecule binds two monovalent hydrogen atoms, therefore, oxygen is divalent. In ammonia, there are three hydrogen atoms per nitrogen atom, therefore, in this compound, nitrogen is trivalent. Finally, in the methane molecule, one carbon atom holds four hydrogen atoms. The tetravalence of carbon is also confirmed by the fact that in carbon dioxide, in full accordance with the theory of valence, a carbon atom holds two divalent oxygen atoms. The establishment of carbon tetravalence played such an important role in the development of organic chemistry, clarified so many confusing questions in this science that the German chemist Kekule (the one who invented the benzene ring) declared: the valence of an element is as constant as its atomic weight. If this belief were true, the task facing Mendeleev would be simplified to the extreme: he would just need to compare the valence of the elements with their atomic weight. But that was the whole difficulty that Kekule had enough over the edge. This interception, necessary and important for organic chemistry, was obvious to every chemist. Even carbon and that in a molecule of carbon monoxide bound only one oxygen atom and was, therefore, not four-, but divalent. Nitrogen, on the other hand, gave a whole range of compounds: M 2 O, N0, M 2 O 3, MO 2, N2O5, in which it was in one-, two-, three-, four- and pentavalent states. In addition, there was another strange circumstance: chlorine, which combines with one hydrogen atom, should be considered a monovalent element. Sodium, two atoms of which are combined with one atom of bivalent oxygen, should also be considered monovalent. It turns out that the monovalent group includes elements that not only have nothing in common with each other, but are downright chemical antipodes. In order to somehow distinguish such elements of the same valence, but not very similar, chemists were forced in each case to make a reservation: monovalent in hydrogen or monovalent in oxygen. Mendeleev clearly lowered the entire "precariousness of the doctrine of the atomicity of elements", but he also clearly understood that atomicity (that is, valence) is the key to classification. "To characterize an element, besides other data, requires two by observation of experience and comparisons of the obtained data: knowledge of atomic weight and knowledge of atomicity." That's when Mendeleev's experience of working on "Organic Chemistry" came in handy, that's when the idea of unsaturated and saturated, extreme organic compounds. In fact, a direct analogy prompted him that of all the valence values that a given element may have, the characteristic one that should be used as the basis for classification should be considered the highest limiting valence. As for the question of which valency - hydrogen or oxygen - to be guided by, Mendeleev found the answer quite easily. While relatively few elements combine with hydrogen, almost all are combined with oxygen, therefore, the form of oxygen compounds - oxides - should be guided when constructing a system. These considerations are by no means baseless guesses. Recently, an interesting table was discovered in the scientist's archive, compiled by Dmitry Ivanovich in 1862, shortly after the publication of Organic Chemistry. This table lists all oxygen compounds of 25 elements known to Mendeleev. And when, seven years later, Dmitry Ivanovich embarked on the final stage, this table undoubtedly served him excellently. Laying out the cards, rearranging them, changing places, Dmitry Ivanovich gazes intently at the meager abbreviated notes and numbers. Here are the alkali metals - lithium, sodium, potassium, rubidium, cesium. How clearly expressed in them "metallicity"! Not the “metallicity” by which any person understands the characteristic luster, malleability, high strength and thermal conductivity, but chemical “metallicity”. "Metallic", causing these soft, fusible metals to rapidly oxidize and even burn in air, producing strong oxides. Combining with water, these oxides form caustic alkalis, which color the litmus blue. All of them are monovalent in oxygen and give surprisingly correct changes in density, melting and boiling points, depending on the increase in atomic weight. But the antipodes of alkali metals - halogens - fluorine, chlorine, bromine, iodine. Dmitry Ivanovich can guess that the lightest of them is fluorine, which is most likely a gas. For in 1869 no one has yet succeeded in isolating fluorine from compounds - the most typical and most energetic of all non-metals. It is followed by the heavier, well-studied gas chlorine, then a dark brown liquid with a pungent odor - bromine, and crystalline iodine with a metallic sheen. Halogens are also monovalent, but monovalent in hydrogen. With oxygen, they give a number of unstable oxides, of which the limiting one has the formula R2O7. This means: the maximum oxygen valence of halogens is 7. A solution of C1 2 O7 in water gives a strong perchloric acid, which turns litmus paper red. Mendeleev's trained eye highlights some more groups of elements, though not as bright as alkali metals and halogens. Alkaline earth metals - calcium, strontium and barium, giving oxides of the RO type; sulfur, selenium, tellurium, forming a higher oxide of the RO3 type; nitrogen and phosphorus with higher oxide R2О5. There is, although not an obvious, chemical similarity between carbon and silicon, which give oxides of the RO2 type, and between aluminum and boron, the highest oxide of which is R2O3. But then everything gets confused, differences are blurred, individualities are lost. And although the existence of separate groups, separate families could be considered an established fact, “the connection between groups was completely unclear: here are halogens, here are alkali metals, here are metals like zinc - they do not transform into each other in the same way as one family into another ... In other words, it was not known how these families were connected to each other. " Nowadays it is easy to show: the meaning of the periodic law is to establish a relationship between the highest valence for oxygen and the atomic weight of an element. But then, more than a hundred years ago, only 63 of the present 104 elements were known to Mendeleev; the atomic weights of ten of them turned out to be underestimated by 1.5-2 times; out of 63 elements, only 17 combined with hydrogen, and the higher salt-forming oxides of many elements decomposed with such a rapidity that they were unknown, therefore their highest valence for oxygen turned out to be underestimated. But the greatest difficulty was presented by elements with intermediate properties. Take aluminum, for example. By its physical properties, it is a metal, but by its chemical properties, you cannot understand what. The combination of its oxide with water is a strange substance, either a weak alkali or a weak acid. It all depends on what it reacts with. WITH strong acid it behaves like an alkali, and with a strong alkali it behaves like an acid. Academician B. Kedrov, a deep connoisseur of Mendeleev's works on the periodic law, believes that Dmitry Ivanovich in his research went from the well-known to the unknown, from the explicit to the implicit. First, he built a horizontal row of alkali metals, so reminiscent of the homologous rows of organic chemistry.

Lf = 7; Na = 23; K = 39; Rb = 85.4; Cs = 133.

Peering into the second pronounced row - halogens - he discovered an amazing pattern; each halogen is lighter than an alkali metal close to it in atomic weight by 4-6 units. This means that a number of halogens can be placed over a number of alkali metals:

F Cl Br J

Li Ns K Rb Cs

P C1 Bg J

Li Na K Rb Cs

Cs Sr Ba

The atomic weight of fluorine is 19; oxygen is closest to it - 16. Is it not clear that above the halogens it is necessary to put a family of oxygen analogs - sulfur, selenium, tellurium? Even higher is the nitrogen family: phosphorus, arsenic, antimony, bismuth. The atomic weight of each member of this family is 1–2 units less than the atomic weight of elements from the oxygen family. As he goes row after row, Mendeleev is more and more strengthened in the idea that he is on the right path. The oxygen valence of 7 for halogens successively decreases when moving upward. For elements from the oxygen family, it is 6, nitrogen - 5, carbon - 4. Therefore, trivalent boron should go further. And exactly: the atomic weight of boron is one unit less than the atomic weight of the carbon that precedes it ... In February 1869 Mendeleev sent many chemists the "Experience of a system of elements based on their atomic weight and chemical similarity" printed on a separate sheet of paper. And on March 6, the clerk of the Russian Chemical Society N. Menshutkin, instead of the absent Mendeleev, read out at a meeting of the society a message about the classification proposed by Dmitry Ivanovich. Studying this vertical version of the Mendeleev table, which is unusual for a modern look, it is easy to make sure that it is, so to speak, open, that rows of elements with less pronounced transitional properties. There were several incorrectly arranged elements in this first version: for example, mercury fell into the group of copper, uranium and gold - into the group of aluminum, thallium - into the group of alkali metals, manganese - into one group with rhodium and platinum, and cobalt and nickel took one a place. The question marks placed near the symbols of some elements indicate that Mendeleev himself doubted the correctness of determining the atomic weights of thorium, tellurium and gold and considered the position of erbium, yttrium and indium in the table to be controversial. But all these inaccuracies should by no means diminish the importance of the conclusion itself: it was this first, still imperfect version that led Dmitry Ivanovich to the discovery of the great law, which prompted him to put four question marks where the symbols of the four elements should have been ... vertical columns, led Mendeleev to the idea that their properties change periodically as their atomic weight increases. This was a fundamentally new and unexpected conclusion, since Mendeleev's predecessors, who were carried away by the contemplation of linear changes in the properties of similar elements in groups, escaped this periodicity, which made it possible to tie together all the groups that seemed disparate. In the "Fundamentals of Chemistry", published in 1903, there is a table with the help of which Dmitry Ivanovich made the periodicity of the properties of chemical elements unusually clear. In a long column, he wrote out all the elements known by that time, and on the right and left he placed numbers showing the specific volumes and melting temperatures, and the formulas of higher oxides and hydrates, and the higher the valence, the further away from the symbol the corresponding formula is. With a cursory glance at this table, you immediately see how the numbers reflecting the properties of the elements periodically increase and decrease as the atomic weight steadily increases. In 1869, unexpected interruptions in this smooth increase and decrease in numbers gave Mendeleev a lot of difficulties. Laying down one row after another, Dmitry Ivanovich discovered that in the column going up from rubidium, after pentavalent arsenic, there is bivalent zinc. A sharp drop in atomic weight - 10 units instead of 3-5, and a complete lack of similarity between. The properties of zinc and carbon, which is at the head of this group, led Dmitry Ivanovich to the idea: in the crosshair of the fifth horizontal row and the third vertical column there should be an unopened tetravalent element, which resembles carbon and silicon in properties. And since zinc had nothing in common with the further group of boron and aluminum, Mendeleev suggested that science still does not know one trivalent element - an analogue of boron. The same considerations prompted him to assume the existence of two more elements with atomic weights of 45 and 180. It took a truly amazing chemical intuition of Mendeleev to make such bold assumptions, and it took his truly immense chemical erudition to predict the properties of not yet discovered elements and correct many delusions, concerning the little-studied elements. It was not by chance that Dmitry Ivanovich called his first table "experience", with this he seemed to emphasize its incompleteness; but in the next year he gave the periodic system of elements that perfect form, which, almost unchanged, has survived to this day. The "openness" of the vertical version, apparently, did not correspond to Mendeleev's ideas about harmony. He felt that from a chaotic heap of parts he had managed to fold the car, but he clearly saw how far this machine was from perfection. And he decided to redesign the table, break the double row that was its backbone, and place alkali metals and halogens on opposite ends of the table. Then all the other elements will appear as if inside the structure and will serve as a gradual natural transition from one extreme to another. And as often happens with ingenious creations, the seemingly formal perestroika suddenly opened up new, previously unsuspected and not guessed connections and comparisons. By August 1869, Dmitry Ivanovich compiled four new sketches of the system. Working on them, he revealed the so-called double similarity between the elements, which he initially placed in different groups. So the second group - the group of alkaline earth metals - turned out to consist of two subgroups: the first - beryllium, magnesium, calcium, strontium and barium and the second - zinc, cadmium, mercury. Further, the understanding of the periodic dependence allowed Mendeleev to correct the atomic weights of 11 elements and change the location of 20 elements in the system! The result of this frantic work in 1871 was the famous article "Periodic validity for chemical elements" and that classic version of the periodic table that now adorns chemical and physics laboratories around the world. Dmitry Ivanovich himself was very proud of this article. In his old age, he wrote: “This is the best collection of my views and considerations about the periodicity of elements and the original, according to which so much was written later about this system. This is the main reason for my scientific fame - because much was justified much later. " And indeed, later on, much was justified, but all this was later, and then ... Now you learn with amazement that most chemists perceived the periodic table only as convenient tutorial for students. In the quoted letter to Zinin, Dmitry Ivanovich wrote: "If the Germans do not know my works ... I will make sure that they know." In keeping with this promise, he asked his fellow chemist F. Vreden to translate into German his fundamental work on the periodic law, and, having received the prints on November 15, 1871, he sent them to many foreign chemists. But, alas, Dmitry Ivanovich did not receive not only competent judgment, but in general no answer to his letters. Neither from J. Dumas, nor from A. Würz, nor from C, Cannizzaro, J. Marignac, V. Odling, G. Roscoe, H. Blomstrand, A. Bayer and other chemists. Dmitry Ivanovich could not understand what was the matter. He flipped through his article over and over and over and over again he was convinced that it was full of exciting interest. Is it not surprising that he, without making any experiments and measurements and based only on the periodic law, proved that the previously considered trivalent beryllium is actually bivalent? Isn't the correctness of the periodic law proved by the fact that, proceeding from It, Mendeleev established the trivalence of thallium, which was previously considered an alkali metal? Is it not convincing that Mendeleev, proceeding from the periodic law, ascribed a valence of three to little-studied indium, which was confirmed several months later by Bunsen's measurements of the heat capacity of indium? And yet this did not convince "Bunsen's daddy" of anything. When one of the young students tried to draw his attention to the Mendeleev table, he only dismissed in annoyance: “Yes, leave me with these guesses. You will find such correctness between the numbers of the exchange leaf. " And Dmitry Ivanovich himself liked the correction of the atomic weights of uranium and a number of other elements, dictated by periodic legality, caused only a reproach from the German physicist Lothar Meyer, to whom, by a strange irony of fate, they subsequently tried to ascribe priority in the creation of the periodic system. "It would be in a hurry," he wrote in the "Liebikhov Annals" about Mendeleev's articles, "to change the atomic weights accepted until now on the basis of such a fragile starting point." Mendeleev was beginning to get the impression that these people listen - and do not hear, they look - and do not see. They do not see the written words in black and white: “The system of elements has not only pedagogical significance, it not only facilitates the study of various facts, putting them in order and connection, but also has a purely scientific significance, discovering analogies and indicating through this new ways to study the elements. " They do not see that “until now we had no reason to predict the properties of unknown elements, we could not even judge the lack or absence of one or another of them ... Only blind chance and special insight and observation led to the discovery of new elements. There was almost no theoretical interest in the discovery of new elements, and therefore the most important field of chemistry, namely the study of elements, has so far attracted only a few chemists. The law of periodicity opens a new path in this last respect, giving a special, independent interest even to such elements as yttrium and erbium, which until now, I must confess, have been interested in only very few. " But Mendeleev was most struck by the indifference to what he himself proudly wrote in his declining years: "It was a risk, but correct and successful." Convinced of the truth of the periodic law, in an article sent to many chemists of the world, he not only boldly predicted the existence of three not yet discovered elements, but also described their properties in the most detailed way. Seeing that this amazing discovery did not interest chemists either, Dmitry Ivanovich made an attempt to make all these discoveries himself. He traveled abroad to purchase minerals containing, as it seemed to him, the required elements. He started a study of rare earth elements. He instructed student N. Bauer to make metallic uranium and measure its heat capacity. But a host of other scientific topics and organizational matters flooded over him and easily distracted him from work that was unusual for his soul. In the early 1870s, Dmitry Ivanovich began to study the elasticity of gases and left time and events to test and check the periodic system of elements, in the truth of which he himself was quite sure. “When I wrote an article in 1871 on the application of the periodic law to the determination of the properties of not yet discovered elements, I did not think that I would live to justify this consequence of the periodic law,” Mendeleev recalled in one of the last editions of “Fundamentals of Chemistry”, “but reality answered differently. I described three elements: ekabor, eka-aluminum and ekasilicon, and before 20 years had passed, I had the greatest joy to see all three open ... ”And the first of the three was eka-aluminum - gallium. Then the discoveries of the elements rained down like a cornucopia! In the classic work "Fundamentals of Chemistry", which survived during the life of the author 8 editions in Russian and several editions in many foreign languages, Mendeleev for the first time presented inorganic chemistry on the basis of the periodic law. Therefore, naturally, the first edition of "Fundamentals of Chemistry" 1869-71. is a welcome item for many collectors and bibliophiles of the world, collecting scientific and technical and priority topics. Naturally, "Fundamentals of Chemistry" was included in the famous PMM, No. 407 and DSB, volume IX, p.p. 286-295. Naturally, they are present at Sotheby’s and Christie’s auctions. Copies autographed by the author are extremely rare!

100 Great Books Demin Valery Nikitich

37. MENDELEEV "BASIS OF CHEMISTRY"

37. MENDELEEV

"BASICS OF CHEMISTRY"

Dmitry Ivanovich Mendeleev is one of the greatest scientists of earthly civilization. He discovered the periodic law of chemical elements. And that's it. There is chemistry before Mendeleev and modern chemistry. Just as there is pre-Darwinian biology and modern science about living matter.

Mendeleev (1834-1907) was “undoubtedly the brightest and perhaps the most complex figure in Russian science of the 19th century,” wrote SP Kapitsa. He was born in the ancient Siberian city of Tobolsk, in the family of the director of the gymnasium was the youngest child. His mother, who came from an educated and enterprising merchant family, played an exceptional role in the formation of his personality as a scientist. In a dedication to the work "Investigation of aqueous solutions by specific gravity" (1887) Dmitry Ivanovich wrote:

This study is dedicated to the memory of the mother by her last child. She could only raise him by her own labor, running a factory business; brought up by example, corrected with love and, in order to give to science, took them out of Siberia, spending the last money and energy. Dying, she bequeathed: to avoid Latin self-delusion, to insist in work, and not in words, and patiently seek divine or scientific truth, for she understood how often dialectics deceives, how much more should be learned and how, with the help of science, without violence, lovingly, but firmly , prejudices, untruths and mistakes are eliminated, and the following are achieved: protection of the acquired truth, freedom of further development, common good and inner well-being. I consider my mother's covenants sacred.

In his high school years, Mendeleev did not differ in particular diligence. He received his higher education in St. Petersburg at the Main pedagogical institute... At the Faculty of Physics and Mathematics, Ostrogradsky taught mathematics, physics - Lenz, pedagogy - Vyshnegradsky, later the Minister of Finance of Russia, chemistry - Voskresensky, "the grandfather of Russian chemists." Beketov, Sokolov, Menshutkin and many other scientists were also his students. Institute Mendeleev graduated in 1855 with a gold medal. A year later, at St. Petersburg University, he received the title of Master of Chemistry and became Associate Professor. Soon Mendeleev was sent abroad and worked for two years in Heidelberg with Bunsen and Kirchhoff. Of great importance for the young Mendeleev was his participation in the congress of chemists in Karlsruhe (1860), where the problem of the atomicity of elements was discussed.

Returning to Russia, Mendeleev became a professor at the St. Petersburg Practical Technological Institute, later - a professor at the St. Petersburg University in the department of technical chemistry and, finally, general chemistry.

Mendeleev was a professor at the University for 23 years. During this time he wrote "Fundamentals of Chemistry", discovered the periodic law and compiled a table of elements. "The periodic law has become the most important generalization in chemistry and the significance of this discovery goes far beyond the limits of this science alone," wrote SP Kapitsa.

Mendeleev's discovery of the periodic law dates back to February 17 (March 1), 1869, when he compiled a table entitled "Experience of a system of elements based on their atomic weight and chemical similarity." This was the result of years of searching. Once, when asked how he discovered the periodic system, Mendeleev replied: "I have been thinking about it for maybe 20 years, but you think: I was sitting and suddenly ... it was ready." Mendeleev compiled several versions of the periodic table and, on its basis, corrected the atomic weights of some known elements, predicted the existence and properties of still unknown elements. At first, the system itself, the corrections made and Mendeleev's forecasts were met with restraint. But after the discovery of the predicted elements (gallium, germanium, scandium), the periodic law began to gain acceptance. The periodic table of Mendeleev was a kind of guiding map in the study of inorganic chemistry and research work in this area. The periodic law became the foundation on which the scientist created his book "Fundamentals of Chemistry".

Having started reading a course in inorganic chemistry at St. Petersburg University, Mendeleev, not finding a single textbook that he could recommend to students, began to write his textbook "Fundamentals of Chemistry". A. Le Chatelier gave the following assessment to this work: “All chemistry textbooks of the second half of the 19th century are built according to the same model, but only one attempt to really move away from classical traditions deserves to be noted - this is Mendeleev's attempt; his chemistry manual has a very special plan. "

In terms of the richness and courage of scientific thought, the originality of the coverage of the material, the impact on the development and teaching of chemistry, this textbook had no equal in the world chemical literature. In the year of Mendeleev's death, the eighth edition of his Fundamentals of Chemistry was published; on the first page he wrote: “These“ Bases ”are my beloved child. They contain my image, my experience as a teacher, my soulful scientific thoughts. "

Mendeleev's range of interests was extremely wide and varied; suffice it to name his work on solutions, research on surface tension, which led Mendeleev to the concept of critical temperature. He was comprehensively involved in the oil business, foreseeing the vital importance of petrochemistry, and was deeply interested in the issues of aeronautics. During the total solar eclipse of 1887, he was supposed to rise in a balloon behind the clouds with an aeronaut. Before the start, because of the rain, the ball got wet and could not lift two of them. Then Mendeleev resolutely landed the pilot and flew alone - this was his first flight. Mendeleev was a brilliant lecturer and passionate propagandist of science.

In 1890, Mendeleev supported the demands of liberal students, and after a clash with the Minister of Education, he left the university. In the following year, he was not for long, but successfully engaged in the technology of production of smokeless powder. In 1893 he became the caretaker of the Main Chamber of Weights and Measures, completely transforming the activities of this institution. Mendeleev connected his work on metrology both with purely scientific tasks and with the practical needs of the commercial and industrial development of Russia. Being close to the leaders of Russia's financial policy - Vyshnegradsky and Witte, the scientist strove through the emerging big bourgeoisie to influence the industrialization of the country. Mendeleev's economic research "Explanatory Tariff" (1890) became the basis of the customs policy of protectionism and played an important role in protecting the interests of Russian industry.

Mendeleev wrote over 400 works. His fame was worldwide: he was a member of more than 100 scientific societies and academies, with the exception of St. Petersburg: he was elected twice and twice blackballed because of the influence and intrigues of the "German" party of the Imperial Academy.

American scientists (G. Seaborg and others), who synthesized element No. 101 in 1955, gave it the name Mendelevium “... in recognition of the priority of the great Russian chemist, who was the first to use the periodic table of elements. To predict the chemical properties of elements that were not yet discovered ”. This principle was the key in the discovery of almost all transuranic elements.

In 1964 Mendeleev's name was entered on the Board of Honor of Science at Bridgeport University (USA) among the names of the greatest scientists in the world.

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MENDELEEV, Dmitry Ivanovich (1834-1907), chemist 602 Trying to cognize the infinite, science itself has no end. "Fundamentals of Chemistry", preface to the 8th ed. (1906)? Mendeleev D.I. - L .; M., 1954, t. 24, p. 49 603 Scientific sowing will grow for the harvest of the people. "Fundamentals of Chemistry", preface to the 8th

"The" Fundamentals of Chemistry "and the periodic law are inseparable from each other, and the correct understanding of the periodic law without the" Fundamentals of Chemistry "is completely impossible." *

* (A. A. Baikov, Proceedings of the Jubilee Mendeleev Congress, vol. I, Ed. Academy of Sciences of the USSR, 1936, p. 28.)

D. I. Mendeleev's discovery of the periodic law coincided in time and is inextricably linked with his work on the book "Foundations of Chemistry", published (in two volumes) in 1869-1871. a large number of additions (the 8th edition was published in 1906). For many years the book "Fundamentals of Chemistry" served as a desk guide and textbook for Russian chemists; she was transferred to a number foreign languages, and was published three times in translation into English (1891, 1897 and 1905). During the years of Soviet power, D.I.

In the second volume of the first edition of "Fundamentals of Chemistry", the main ideas of periodicity are set forth and the natural system of elements is placed. In principle, it differs little from the previous version; it also contains the coordinates "row" - "group", and the intersections of the lines of the row and the group correspond to a certain element. The formulas of the most typical compounds are placed under the symbols of the elements, which cluttered the table (in subsequent versions of the formulas were excluded).

The last element in the system was uranium, for which D. I. Mendeleev, based on the periodic law, changed the atomic weight from 116 to 240. With regard to uranium, he wrote:

"Interest in further study increases with a change in atomic weight also because its atom turns out to be the heaviest of all known elements ... Convinced that the study of uranium, starting from its natural sources, will lead to many more new discoveries, I boldly recommend those who are looking for subjects for new research, especially carefully deal with uranium compounds "...

DI Mendeleev put five dashes behind uranium, corresponding to five still unknown elements with atomic weights of 245-250, which was an indication of the possibility of discovering transuranium elements, which was later confirmed (after 1940, 12 elements were artificially obtained behind uranium).

Proceeding from the fact that the properties of any element X are in a natural connection with the properties of neighboring elements (Fig. 1) along the horizontal (D, E), vertical (B, F) and diagonals (A, H and C, G), D. I. Mendeleev uses this "stardom", or atomanalogy *, to predict 11 still unknown elements: ecacesium, ekabarium, ekabor, ekaaluminium, ekalantana, ekasilicia, ekatanthal, ekatellur, ekamarganese, dimarganese and ekaiod **. With regard to three of them - ekabora, ekaaluminium and ekasilicia (the conventional symbols of which are Eb, Ea, Es) - Mendeleev had a particularly strong belief in the possibility of their discovery.

* (The properties of an element must be the arithmetic mean of the properties of the elements surrounding it.)

** (The prefix eka means one more, and two means the second.)

In the period between the publication of the second (1872) and third (1877) editions of the book "Fundamentals of Chemistry", DI Mendeleev's prediction was confirmed. The French chemist Lecoq de Boisbaudran in 1875 discovered a new element - gallium, the properties of which, established experimentally, strikingly coincided with the properties of the predicted ekaaluminium (Table 7).

Initially, de Boisbaudran determined the density of gallium to be 4.7. Mendeleev in a letter to him indicated that this value is erroneous and is the result of working with an impure sample, but in reality the density of gallium should be equal to 5.9-6.0. In the second determination of the density of gallium purified from impurities, a value of 5.904 was obtained.

Mendeleev's works were not known to de Boisbaudran and his discovery is not associated with the periodic law. However, he later wrote:

"I think there is no need to insist on the enormous importance of confirming Mr. Mendeleev's theoretical conclusions regarding the density of the new element."

The genius of D. I. Mendeleev's foresight delights K. A. Timiryazev:

"Mendeleev announces to the whole world that somewhere in the universe ... there must be an element that the human eye has not yet seen, and this element is, and the one who finds it with the help of his senses sees it for the first time worse than saw him with the mental gaze of Mendeleev. " *

* (K. A. Timiryazev, "Scientific problems of modern natural science", Ed. 3rd, Moscow, 1908, p. 14.)

The discovery of gallium gave DI Mendeleev confidence in the truth of the periodic law, and in the third edition of Fundamentals of Chemistry, he introduces a new chapter - "Similarity of Elements and Their System (Isomorphism), Form of Compounds, Periodic Law, Specific Volumes". Another chapter lists all the known data on the properties of gallium. This element was first introduced in a variant of the system called the "Periodic table of chemical elements based on their atomic weight and chemical similarity."

At the end of 1879, the Swedish scientist Nilsson discovered the ekabor predicted by DI Mendeleev and named the new element scandium (Table 8). Nilsson wrote about the coincidence of the predicted and experimentally found properties of the new element:

"... there is no doubt that an ekabor was discovered in scandium ...; this is how the thoughts of the Russian chemist are confirmed in the most graphic way, which made it possible not only to foresee the existence of the named simple body, but also to give its most important properties in advance."

In the fourth edition of "Fundamentals of Chemistry" (1882), the new element is included in the system of elements and data on its properties are given. Before the value of the atomic weight 72, Mendeleev, waiting for the discovery of this element, put question marks (Table 9).

At the top of the table are elements of even, at the bottom - odd rows.

("Fundamentals of Chemistry", ed. 4th, part I, St. Petersburg, 1881, p. XVI.)

The periodic law won a decisive victory in 1886, when the German chemist Winkler discovered a new element, germanium. The properties established for this element empirically coincided with the properties indicated by Mendeleev for ekasilicon (Table 10).

Regarding the discovery of germanium, Winkler noted:

"... the study of its properties is an unusually attractive task also in the sense that this task is, as it were, a touchstone of human insight. There can hardly be a clearer proof of the validity of the doctrine of the periodicity of elements than the discovery of the hitherto hypothetical" ekasilicia " ; it is, of course, more than a simple confirmation of a bold theory, it marks an outstanding expansion of the chemical field of vision, a giant step in the field of knowledge. "

Answering Winkler, in 1886 Mendeleev wrote:

"In our time (of action) hardly anyone will be interested in statements alone, therefore we must regard as statements making an era that have received their real implementation." (Emphasized by us - V.S.)

In the fifth edition of the book "Fundamentals of Chemistry" (1889), germanium was included in the system of elements in the place assigned to it in advance and its properties were described.

After the discovery of germanium, DI Mendeleev's periodic law received worldwide recognition, and the periodic system became a necessary tool for studying chemistry. but further development chemistry, the discovery of new elements and the study of their properties caused the need for additions and changes to the periodic system, determining the place of new elements in it and resolving controversial issues that did not pass without doubts and difficulties. An example of this is the discovery of inert gases.

In 1894, the British scientists Rayleigh and Ramsay found that under normal conditions a liter of nitrogen released from the air (after removing water vapor, carbon dioxide and oxygen from it) weighs 1.2572 g, and a liter of nitrogen obtained by decomposition of nitrogen-containing substances, weighs less - 1.2505 g. This difference could not be explained by an experimental error, in connection with which it was assumed that the nitrogen obtained from the air contains an unknown heavier gas. By passing nitrogen through heated magnesium (this produces magnesium nitride), the scientists chemically bound the nitrogen and isolated the unknown gas. It was found that the molecule of this gas is monoatomic, the atomic weight is 40, and the gas atoms do not combine with each other and with the atoms of other elements. The gas turned out to be chemically inactive, and therefore was called argon ("lazy") and designated by the symbol A (later Ar).

At first, D.I. in addition to Chapter V of the sixth edition (1896) of Fundamentals of Chemistry, he nevertheless gave a description of a new element - argon.

* (A cell corresponding to an atomic weight of 40 in the periodic table was occupied by calcium.)

Further research by Ramsay confirmed the elementary nature of argon, and on the basis of the periodic table, he expressed the idea of the existence of a group of such elements:

"Following the model of our teacher Mendeleev, I described, as far as possible, expected properties and intended relationships." Using the Mendeleev method, J. Thomsen predicts the atomic weights of the putative elements.

Soon Ramsay and Travers discovered four more inert gases: helium, neon, krypton, and xenon. Herrera proposed introducing a zero group in the system for these elements, while others considered it possible to include them in group VIII (as it is accepted at the present time).

The discovery of inert gases was an unexpected event (except for the foresight of N. A. Morozov, see p. 51) and Mendeleev did not foresee their place in the periodic table. Nevertheless, he came to the following conclusion:

"... More than before, I began to be inclined to believe that argon and its analogs are elementary substances with a special set of properties, which are by no means in the VIII group (as some people think), but that form a special (zero) group."

In the seventh edition of "Fundamentals of Chemistry" inert gases in the periodic table are placed in the zero group. This group in one version (with vertical periods) is placed after the group of halogens, and in the other (with horizontal periods) - before alkali metals (Table 11). The system also includes radium, discovered by M. Curie-Sklodowska and P. Curie in 1898. There are 71 elements in the system. Since argon is in the system up to potassium, the atomic weight of which is 39.15, Mendeleev takes the atomic weight for argon to be 38, although experimental data led to a value of 39.9.

This version of the system was reproduced without changes in the eighth, last edition of Fundamentals of Chemistry (1906), published during the life of D.I. law "," On primary matter "," On the atomic weights of nickel and cobalt, tellurium and iodine and on rare earth elements "," On the forms of representation of the periodic law "," The laws of nature do not tolerate exceptions "," Periodicity belongs to elements, not compounds ". All these questions were of no small importance for the problem of the periodic law. An objective assessment of the history of the discovery of the periodic law was given by Mendeleev himself:

"Thus, the periodic legitimacy directly flowed from the stock of rapprochements and verified information that existed by the end of the 60s, it is a collection of them into one more or less systematic, integral expression ..."

D. I. Mendeleev considered the discovery of gallium, scandium, germanium and inert gases to be the most important events in the development and approval of the periodic law:

"When I wrote an article in 1871 on the application of the periodic law to the determination of the properties of elements not yet discovered, I did not think that I would live to justify this consequence of the periodic law, but reality answered differently. I described three elements: ekabor, ekaaluminium and ekasilicium, and less than 20 years have passed since I had the greatest joy to see all three discovered and named after those countries where rare minerals containing them were found and where their discovery was made: gallium, scandium and germanium.L. de Boisabaudran, Wilson and Winkler who discovered them, I, for my part, consider the true strengtheners of the periodic law. Without them, he would not have been recognized to the extent that it happened now. To the same extent, I consider Ramsay an affirmator of the justice of the periodic law, since he discovered He, Ne, Ar, Kr and Xe, determined their atomic weights, and these numbers are quite suitable for the requirements of the periodic table of elements. " ("Fundamentals of Chemistry", ed. 13, vol. II, 389-390).

Mendeleev also includes the Czech scientist Brauner among the "strengtheners" of the periodic law, whose experimental work was associated with the periodic system, with the development of methods for determining atomic weights and studying the properties of rare earth elements. DI Mendeleev also mentions the works of LV Pisarzhevsky in the field of studying the structure and properties of peroxides and peracids, which were of no small importance for the periodic law.

"Fundamentals of Chemistry" by D. I. Mendeleev is not only a textbook that sets out in a logical and historical sequence the process of the development of chemistry as a science, but also a wonderful fundamental work that introduces into this science a fundamentally new content, system and means of cognition of all the material accumulated by it ...

Many have heard about Dmitry Ivanovich Mendeleev and about the "Periodic Law of Changes in the Properties of Chemical Elements by Groups and Rows" discovered by him in the 19th century (1869) (the author's name of the table is "Periodic Table of Elements by Groups and Rows").

The discovery of the table of periodic chemical elements became one of the important milestones in the history of the development of chemistry as a science. The discoverer of the table was the Russian scientist Dmitry Mendeleev. An extraordinary scientist with the broadest scientific outlook managed to combine all ideas about the nature of chemical elements into a single harmonious concept.

Table opening history

By the middle of the 19th century, 63 chemical elements were discovered, and scientists around the world have repeatedly made attempts to combine all existing elements into a single concept. The elements were proposed to be placed in the order of increasing atomic mass and divided into groups according to the similarity of chemical properties.

In 1863, chemist and musician John Alexander Newland proposed his theory, who proposed a layout of chemical elements similar to that discovered by Mendeleev, but the scientist's work was not taken seriously by the scientific community due to the fact that the author was carried away by the search for harmony and connection of music with chemistry.

In 1869, Mendeleev published his scheme of the periodic table in the journal of the Russian Chemical Society and sent a notice of the discovery to the world's leading scientists. In the future, the chemist refined and improved the scheme more than once until it acquired its usual form.

The essence of Mendeleev's discovery is that with an increase in atomic mass Chemical properties elements change not monotonously, but periodically. After a certain number of elements of different properties, the properties begin to repeat. So, potassium is similar to sodium, fluorine is similar to chlorine, and gold is similar to silver and copper.

In 1871, Mendeleev finally united the ideas into a periodic law. Scientists predicted the discovery of several new chemical elements and described their chemical properties. Subsequently, the chemist's calculations were fully confirmed - gallium, scandium and germanium fully corresponded to the properties that Mendeleev attributed to them.

But not everything is so simple and we do not know something.

Few of those who know that D.I.Mendeleev was one of the first world-famous Russian scientists of the late 19th century, who defended in world science the idea of ether as a universal substantial entity, who gave it fundamental scientific and applied significance in revealing the secrets of Being and to improve the people's economic life.

There is an opinion that the Mendeleev table of chemical elements officially taught in schools and universities is a fake. Mendeleev himself, in his work titled "An Attempt at a Chemical Understanding of the World Ether", gave a slightly different table.

The last time in an undistorted form this periodic table was published in 1906 in St. Petersburg (textbook "Fundamentals of Chemistry", VIII edition).

The differences are visible: the zero group has been moved to the 8th, and the element is lighter than hydrogen, with which the table should begin and which is conventionally called Newtonium (ether), is completely excluded.

The same table is immortalized by the "BLOODY TIRAN" comrade. Stalin in St. Petersburg, Moskovsky Prospect. 19. VNIIM them. D. I. Mendeleeva (All-Russian Research Institute of Metrology)

Monument-table Periodic table of chemical elements of D.I. The monument is based on a table from the last lifetime 8th edition (1906) of the Fundamentals of Chemistry by D.I.Mendeleev. Elements discovered during the life of DI Mendeleev are marked in red. Elements discovered from 1907 to 1934 are marked in blue.

Why and how did it happen that they lie to us so brazenly and openly?

The place and role of the world ether in the true table of D. I. Mendeleev

Many have also heard that D.I. Mendeleev was the organizer and leader (1869-1905) of a Russian public scientific association called the Russian Chemical Society (since 1872 - the Russian Physico-Chemical Society), which published throughout its existence the world-famous journal ZhRFHO, up to until the liquidation by the Academy of Sciences of the USSR in 1930 - both the Society and its journal.
But there are few of those who know that D.I.Mendeleev was one of the last world famous Russian scientists of the late 19th century who defended in world science the idea of ether as a universal substantial entity, who gave it fundamental scientific and applied significance in revealing secrets Being and to improve the people's economic life.

Even fewer are those who know that after the sudden (!!?) Death of D.I. law ”- was deliberately and widely falsified by world academic science.

And there are very few of those who know that all of the above is linked together by the thread of sacrificial service of the best representatives and carriers of the immortal Russian Physical Thought for the good of the peoples, for the public benefit, despite the growing wave of irresponsibility in the upper strata of society of that time.

In essence, this dissertation is devoted to the all-round development of the last thesis, for in genuine science any neglect of essential factors always leads to false results.

The elements of the zero group begin each row of other elements, located on the left side of the Table, “... which is a strictly logical consequence of understanding the periodic law” - Mendeleev.

Particularly important and even exclusive in the sense of the periodic law, the place belongs to the element "x" - "Newton" - the world ether. And this special element should be located at the very beginning of the entire Table, in the so-called "zero group of the zero row". Moreover, being a backbone element (more precisely, a backbone entity) of all elements of the periodic table, the world ether is a substantial argument of the whole variety of elements of the periodic table. The Table itself, in this regard, acts as a closed functional of this very argument.

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