Dmitri Mendeleev

MENDELEEV, Dmitry Ivanovich (1834–1907), the greatest of Russian chemists, was born in Tobolsk, into the family of the director of the Tobolsk gymnasium, as the nineteenth child. In his childhood, his upbringing and education were guided by his mother, to whom he owed a great deal. Upon graduating from the Tobolsk gymnasium at the age of 16, .- ', .- '-*.« «ft.

he entered the Main Pedagogical Institute in Saint Petersburg, from which he graduated in 1854. In early 1856 he defended his candidate's dissertation on isomorphism (Saint Petersburg, 1856) and in the same year his master's dissertation "Specific Volumes" (Saint Petersburg, 1856). In 1859 he was sent abroad for two years, where he worked first in Paris under the guidance of Regnault and then in Heidelberg. Here he set up a small private laboratory, where he studied capillarity, thermal expansion, and compressibility of liquids, and performed his well-known investigations on the "absolute boiling point," subsequently named the "critical temperature." Upon his return to Saint Petersburg in 1861, he published an original course in organic chemistry (Saint Petersburg). In 1863 he was elected professor at the Technological Institute, became interested in a number of industrial and agricultural problems, made several trips to the Caucasus to study the Baku oil fields, and advocated the necessity of developing the oil industry in Russia. In 1865 he defended his doctoral dissertation on the combination of alcohol with water (Journal of the Russian Physico-Chemical Society, 1837 [note: year error in OCR], iss. 5, chem. part, sect. 1, p. 335), which was of great technical significance, creating the basis for a rational system of alcoholometry used in Holland and Germany, and subsequently in Russia, and at the same time of great scientific value, since it was the first to set forth the basic provisions of the chemical theory of hydration. In 1867 Mendeleev was elected to the chair of chemistry at the University of Saint Petersburg, where he taught until 1890; during student unrest he sided with the students, resigned, and transferred (in 1893) to service in the more liberal Ministry of Finance, where he became head of the newly organized Main Chamber of Weights and Measures. Here he established a number of departments, conducted subtle investigations in metrology, especially on the theory of analytical balances and the renewal of Russian prototypes of units of length and mass. The result of these investigations was three works, of which the last and most important is "An Experimental Investigation of Balance Oscillations" (Saint Petersburg, 1898; republished in 1931). Mendeleev's scientific interests were extremely vast and diverse. He worked extensively on the investigation of gases and vapors, and was interested in the Earth's atmosphere, air resistance, and meteorological phenomena. Under his editorship, Mohn's major course in meteorology was published. In 1887 he undertook a solo flight in a free balloon without a pilot and made a series of meteorological observations during a solar eclipse. Studying the oil industry, he became interested in the origin of oil and created an original theory of its mineral origin. From the oil industry, Mendeleev's interests spread to other industrial and economic problems. Mendeleev holds the idea of the underground gasification of coal, the experimental development of which is being carried out in our country. He wrote "The Explanatory Tariff" (iss. 1–3, Saint Petersburg, 1891) and "To the Knowledge of Russia" (Saint Petersburg, 1906), in which he argued for the necessity of the industrialization of our country. In the last years of his life, he worked extensively on assignments for the War Department and created a new type of smokeless powder, "pyrocollodion," which yielded excellent results. Finally, Mendeleev was interested in painting, and for many years a circle of Wanderers (Peredvizhniki) artists gathered in his home. Despite such a diversity of occupations and interests, Mendeleev's main work of his life remained his writings in chemistry. In this field he created the chemical theory of solutions, which asserted the presence of chemical bonds and definite chemical compounds between the constituent parts of a solution. In his time this theory did not have great success, because under the influence of the works of van 't Hoff, Arrhenius, and Ostwald, a physical view of solutions began to establish itself. But later, when the infatuation with the physical theory passed, Mendeleev's views were revived in the form of the hydrate theory. The greatest work of Mendeleev, which brought him worldwide fame and advanced Russian chemistry to the front ranks of world science, was his creation of the periodic system of the elements (see), completed essentially in 1869. This Mendeleev periodic table was the first successful attempt at a rational classification of elements and was soon adopted by chemists all over the world. Its success was particularly facilitated by the circumstance that Mendeleev had the courage to predict the properties of elements unknown at his time, which were to fill the empty spaces of his table. Even during his lifetime, the elements predicted by him (Ga, Sc, and Ge) were discovered in France, Norway, and Germany, and their properties exactly matched Mendeleev's expectations. The "noble gases" subsequently discovered in England (He, Ne, Ar, Kr, Xe) also easily fit into Mendeleev's system, which had to be supplemented with a new (zero) group. The success of Mendeleev's system was so great that a dispute over priority flared up around it. Mendeleev himself did not participate in it. English scientists, arguing with German ones, championed his honor. To Mendeleev it brought worldwide renown and loud fame: he was awarded orders and medals, and elected an honorary member and doctor of many foreign academies and universities. Only the Russian Academy did not deem it necessary to make him its member: in view of the sharpness of his character, Mendeleev was on bad personal terms with many academicians. Mendeleev's periodic system has successfully stood the test of time: in the field of the doctrine of elements and their atoms, the greatest discoveries have been made since Mendeleev's time and a new science of the structure of matter has been created. Nevertheless, the table created by Mendeleev did not require modification, and the systematics of elements proposed by him is confirmed by recent work. To a certain extent, only its interpretation has changed: Mendeleev attributed the primary role to the atomic weight of the element, whereas at present this role is played by the atomic number in Mendeleev's table, equal to the number of nuclear charges. But the order of the elements remains the same, and almost all the empty spaces in his table have gradually been filled. The most important role of this system lies in the fact that it still pushes scientists to search for new paths and gives rise to new astonishing discoveries. The most complete exposition of Mendeleev's periodic system was found in his remarkable chemistry course, "Principles of Chemistry," which went through 8 editions in Russian during Mendeleev's lifetime and 4 editions after his death. In addition, it was translated into German and French and published 3 times in England. Engels, characterizing Mendeleev as the creator of the periodic system, says: "Mendeleev, unconsciously applying the Hegelian law of the transition of quantity into quality, accomplished a scientific feat which can boldly be placed alongside the discovery of Leverrier, who calculated the orbit of the yet unknown planet Neptune." Being a great revolutionary in chemistry, Mendeleev was distinguished by a conservatism in his understanding of socio-political life, and was a principled opponent of socialism. His activity took place during a period when the bourgeoisie played a progressive role, and Mendeleev, fighting for the development of industry and agriculture on a capitalist basis, remained a prisoner of his class and his time. But the demands that Mendeleev put forward regarding the use of natural resources, the industrialization of the country, the chemicalization of agriculture, the development of the Arctic, the study of the atmosphere, and others, could only to a very small extent be satisfied under the conditions of the capitalist system and are only now being implemented.