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BIOGRAPHIES OF GREAT SCIENTISTS
Kekule August Friedrich von Stradonitz. Biography of a scientist
Directory / Biographies of great scientists
Friedrich August Kekule von Stradonitz was born on September 7, 1829 in Germany. The boy was amazingly gifted. Even at school, he could speak four languages fluently, had literary abilities. According to the project of the high school student Kekule, three houses were built! However, a few weeks before August graduated from school, his father died. After the death of his father, the question of mastering a profitable profession arose with particular urgency. On the advice of his relatives, August left for Giessen, where his brother Emil had been studying at the university for a year. At the university, August began to study geometry, mathematics, drawing, drawing. He possessed an extraordinary gift of eloquence, knew how to tell a fascinating story, knew how to tactfully give the necessary advice, and soon became everyone's favorite. At the university, August first heard the name of Justus Liebig. The students pronounced it respectfully, with delight. August Kekule decided to attend lectures of the famous scientist, although he was not interested in chemistry. In the spring of 1848, Kekule entered Liebig's laboratory for the first time. The world-famous professor made an indelible impression on him. Already after the first lecture, August decided that he would constantly go to Liebig's classes, and every day chemistry fascinated him more and more. Soon, having abandoned architecture, he firmly decided that he would study chemistry. But, having arrived for the summer holidays, at the insistence of his relatives, August was forced to stay in Darmstadt and enter the Higher Vocational School. And yet, making sure that Augustus did not intend to abandon his choice, his relatives agreed to let him go back to Giessen. In the spring of 1849 he continued his studies in analytical chemistry. His first scientific work on amylsulfuric acid was highly appreciated by Professor Bill. For her, in June 1852, the Academic Council of the University awarded Kekula a doctorate in chemistry. After graduating from the university, the young scientist worked for some time in Switzerland with Adolf von Plant, and then moved to London, where he was recommended the laboratory of John Stenhouse. Numerous and lengthy analyzes tired him and bothered him with their monotony. He found satisfaction after a busy day in evening conversations with fellow compatriots. Theoretical and philosophical problems of organic chemistry were the main subject of their judgments. Such concepts as "connective weight", "atomic weight", "molecule" caused a lot of controversy. The theory of types, created by Gerard, proved that the replacement of one element by another takes place in those cases when an element participates in the reaction, the weight of which is two, three or four times greater than the connecting weight. Frankland introduced the concept of "atomicity", what is now called valency. Frankland's ideas were developed by William Odling, who suggested that the valency of elements be denoted by a dash at the chemical symbol. The question of valence was extremely occupied by Kekule, and the ideas of experimental verification of certain theoretical propositions, which he decided to present in the article, gradually matured in his mind. In it, Kekule made an attempt to generalize and expand the theory of types developed by Gerard. Kekule compared his conclusions with the main provisions of Odling's theory. The concept of "valency" of atoms can be used as the basis of a new theory! Atoms are connected according to some simple pattern. He imagined the atoms of the elements in the form of small spheres, which differ from each other only in size. Unfortunately, the intense and tedious work in Stenhouse's laboratory filled almost all the time, and Kekule did not have the opportunity to think over and test by experience the thoughts that did not give him rest. I had to look for another job. In the spring of 1855, Kekule left England and returned to Darmstadt. He visited the universities of Berlin, Giessen, Göttingen and Heidelberg, but there were no vacancies. Then he decided to ask permission to be appointed as Privatdozent in Heidelberg. Robert Bunsen, professor of chemistry at the University of Heidelberg, approved the idea. In his opinion, Kekule's lectures should have attracted listeners, since many students were interested in organic chemistry. Having received permission, the scientist rented a room in a large three-story house that belonged to a flour merchant. He took one room for an audience, and arranged a laboratory in the other. There was not enough space, only two worktables fit in the laboratory, but Kekule was pleased. At first, only six people attended Kekule's lectures on organic chemistry, but gradually the audience filled up, and Kekule's income increased - each listener contributed a certain amount. Now Kekule could devote all his free time to research work. He focused his attention on explosive acid and its salts, the structure of which was still unclear. He managed to expand and supplement the theory of types. Kekule added one more to the main ones - a type of methane. He outlined his conclusions in the article "On the constitution of mercury fulminate." Alas, the scientist did not have the means to again take up experiments with explosive acid. He decided to come to grips with theoretical problems. In the article "On the Theory of Polyatomic Radicals" Kekule formulated the main provisions of his theory of valency. He generalized the conclusions of Frankland, Williamson, Odling and developed the question of the connecting ability of atoms. The number of atoms of one element associated with one atom of another element depends on the valence, that is, on the magnitude of the affinity of the constituent parts. In this sense, elements are divided into three groups: monovalent, divalent and trivalent. In the same article, Kekule noted that carbon occupies a special place among all elements. In organic compounds, its valence is four, since it combines with four equivalents of hydrogen or chlorine. Thus, organic carbon compounds require special study. In the article "On the Composition and Transformations of Chemical Compounds and on the Chemical Nature of Carbon", Kekule substantiated the tetravalence of carbon in organic compounds. He also noted that Gerard's attempt to bring all chemical reactions under one general principle - double exchange - is unjustified, since there are reactions of direct combination of several molecules into one. Considering the composition of organic radicals in a new light, he wrote: “Regarding substances containing several carbon atoms, it must be assumed that the atoms of other elements are retained in the organic compound due to the affinity (valence) of carbon; the carbon atoms themselves also combine with each other, and part affinity (valency) of one carbon atom is saturated with the same amount of affinity (valency) of another carbon atom. These were completely new ideas, ideas about carbon chains. It was a revolution in the theory of organic compounds. These were the first steps in the theory of the structure of organic compounds. A. M. Butlerov, thanks to a critical analysis of the work of Kekule and Cooper, was able to lay the basic provisions of the theory of the chemical structure of organic compounds, which was created by a Russian scientist a few years later. In the spring of 1858, Joseph Moreska, a teacher of chemistry at the University of Ghent (Holland), died. It was decided to invite a chemist from Germany to the vacant position. At the end of 1858, Kekule left for Ghent with his assistant Adolf Bayer. Here the scientist continued his research work. He was still preoccupied with the question of carbon chains. He believed that during chemical reactions, the carbon chain remains unchanged. It's time to prove it empirically. Gradually gaining facts, he confirmed his point of view. During the construction of a chemical laboratory in Ghent, Kekule met the director of a lighting gas plant. Mr. Drory, an Englishman by origin, personally supervised the installation work. He often came to Kekula to take his soul - to talk to him in his native language, and the scientist spoke English perfectly. Gradually, he became close to the director's family. The director's daughter, the beautiful Stephanie, captured August's heart. The girl received an excellent education. The beauty of her delicate, delicate face, flexible and sharp mind conquered Kekule. Young people fell in love with each other at first sight. Mr. Drori favorably reacted to Kekule's proposal, but advised to postpone the wedding until next summer, so that the newlyweds could make their honeymoon during Kekule's summer vacation. In addition, in the near future Kekule was to go to a congress of natural scientists in Speyer. At one of the meetings of this congress on September 19, 1861, Butlerov made a report "On the chemical structure of substances." Kekule was very skeptical about the new structural formulas, which, according to Butlerov, expressed not only the arrangement of atoms in a molecule, but also showed what their mutual influence was. Disillusioned with the theory of types, Kekule did not accept Butlerov's new theory either. Returning to Ghent, he continued his research on fumaric and maleic acids. There was no doubt that these acids were isomeric compounds. But how to explain their isomerism. The scientist spent many sleepless nights, but so far he could not find an explanation. The long-awaited wedding, which took place in the summer of 1862, was a release of enormous spiritual tension. How much joy and happiness Stephanie brought him! His strength seemed to have doubled - returning from his honeymoon, he worked with even greater enthusiasm: he conducted experiments with unsaturated acids, finished the manuscript of a textbook of organic chemistry. But this happy period was short-lived: the upcoming motherhood of Stephanie brought anxiety for her health. Kekule was very concerned about his wife's condition. And the worst fears were confirmed - the birth of a son cost the mother's life. Kekule was inconsolable in grief. Kekule, seeking solace in his work, set about studying the structure of benzene and its derivatives. The atoms in a molecule mutually influence each other, and the properties of the molecule depend on the arrangement of the atoms. Kekule imagined carbon chains as snakes. They wriggled, took a variety of positions, gave or attached atoms, turning into new compounds. He was close to the solution, and yet he could not imagine the structure of benzene. How are the six carbon and six hydrogen atoms arranged in its molecule? Kekule made dozens of suggestions, but on reflection he discarded them. There are several versions of how Kekule discovered the formula of benzene. According to one of them, she dreamed of him. Waking up, the scientist hurriedly sketched a new form of chain on a piece of paper. This is how the first ring formula of benzene appeared ... The idea of a benzene ring gave a new impetus to experimental and theoretical research. Kekule sent the article "On the Structure of Aromatic Compounds" to Wurtz, who presented it to the Paris Academy of Sciences. The article was published in the Bulletin of the Academy in January 1865. Science has been enriched by yet another new, exceptionally fruitful theory of the structure of aromatic compounds. Further research in this area led to the discovery of various isomeric compounds, many scientists began to conduct experiments to elucidate the structure of aromatic substances, proposed other formulas for benzene ... But Kekule's theory turned out to be the most legitimate and soon established itself everywhere. Based on his theory, Kekule predicted the possibility of the existence of three isomeric compounds (ortho, meta and para) in the presence of two substituents in the benzene ring. Another field of activity opened before scientists, the possibility of synthesizing new substances appeared. In 1867, Kekule was appointed director of the new Institute of Chemistry at the University of Bonn. O. Ballach, L. Kleisen, G. Schultz, R. Anschütz and others worked in the laboratory together with Kekule. Many of them later became famous scientists. The glory of Kekule as one of the most prominent scientists was universally recognized. He was elected an honorary member of many academies of the world, not only scientists, but also industrialists considered his opinion. Until his very old age, Kekule continued to work with unflagging energy: he conducted experiments, read reports. In the spring of 1896, an influenza epidemic broke out in Berlin. The disease greatly undermined the health of Kekule, who had long suffered from chronic bronchitis. On July 13, 1896, the great scientist died. Author: Samin D.K.
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