Dmitry Ivanovich Mendeleyev

Russian chemist

• Born: February 8, 1834
• Birthplace: Tobolsk (now Tyumen Oblast), Siberia, Russia
• Died: February 2, 1907
• Place of death: St. Petersburg, Russia

Although he did important theoretical work on the physical properties of fluids and practical work on the development of coal and oil resources, Mendeleyev is best known for his discovery of the periodic law, which states that the properties of the chemical elements vary with their atomic weights in a systematic way. His periodic table of the elements enabled him accurately to predict the properties of three unknown elements, whose later discovery confirmed the value of his system.

Early Life

Dmitry Ivanovich Mendeleyev (myehn-dyih-LYAY-yehf ) was born in an administrative center in western Siberia. He later recalled that he was the seventeenth child, but a sister claimed that he was actually the sixteenth child, and many scholars state that he was the fourteenth. His mother, Marya Dmitrievna Kornileva, came from an old merchant family with Mongolian blood. She became deeply attached to her youngest son and played an influential role in shaping his passionate temperament and directing his education. His father, Ivan Pavlovich Mendeleyev, was a principal and teacher at the Tobolsk high school, but shortly after his son’s birth he became totally blind. The modest disability pension he received did not allow him to support his large family, and so Marya, a remarkably able and determined woman, reopened a glass factory that her family still owned in a village near Tobolsk. She ran it so successfully that she was able to provide for her family and complete her younger children’s education.

In the Tobolsk schools, young Dmitry, an attractive curly-haired, blue-eyed boy, excelled in mathematics, physics, geography, and history, but he did poorly in the compulsory classical languages, Latin in particular. Tobolsk was a place for political exiles, and one of Dmitry’s sisters wedded an exiled Decembrist, one of those who tried unsuccessfully in December, 1825, to overthrow Czar Nicholas I. He took an active interest in Dmitry, taught him science, and helped form his political liberalism.

Toward the end of Mendeleyev’s high school education, a double tragedy occurred: His father died of tuberculosis and his family’s glassworks burned to the ground. By this time, the older children had left home, leaving only Dmitry and a sister with their mother, who decided to seek the help of her brother in Moscow. After Dmitry’s graduation from high school in 1849, Marya, then fifty-seven years old, secured horses and bravely embarked with her two dependent children on the long journey from Siberia. In Moscow, her brother, after first welcoming them, refused to help his nephew obtain an education on the grounds that he himself had not had one. Marya angrily left Moscow for St. Petersburg, where she again encountered difficulty in getting her son either into the university or into the medical school.

Finally, through a friend of her dead husband, Mendeleyev’s mother secured a place for him in the faculty of physics and mathematics of the Main Pedagogical Institute, the school his father had attended. Three months later, Marya died, and not long afterward her daughter succumbed to tuberculosis. Mendeleyev, who also suffered from tuberculosis, later wrote that his mother instructed him by example, corrected him with love, and, in order to consecrate him to science, left Siberia and spent her last energies and resources to put him on his way.

Mendeleyev received a good education at the Pedagogical Institute. One of his teachers had been a pupil of Justus von Liebig, one of the greatest chemists of the time. In 1855, Mendeleyev, now qualified as a teacher, was graduated from the Pedagogical Institute, winning a gold medal for his academic achievements.

Worn out by his labors, he went to a physician, who told him that he had only a short time to live. In an attempt to regain his health, he was sent, at his own request, to the Crimea, in southern Russia. He initially taught science at Simferopol, but when the Crimean War broke out, he left for Odessa, where he taught in a local lyceum during the 1855-1856 school year and where, aided by the warm climate, his health improved. In the autumn of 1856, he returned to St. Petersburg to defend his master’s thesis. He succeeded and obtained the status of privatdocent, which gave him the license to teach theoretical and organic chemistry at the University of St. Petersburg.

Life’s Work

In his teaching, Mendeleyev used the atomic weights of the elements to explain chemistry to his students. This did not mean that he believed that chemistry could be completely explained by physics, but his work on isomorphism and specific volumes convinced him that atomic weights could be useful in elucidating chemical properties. To improve his understanding of chemistry, he received in 1859 a stipend for two years’ study abroad.

In Paris, Mendeleyev worked in the laboratory of Henry Regnault, famous for his studies on chlorine compounds, and at the University of Heidelberg, where he had the opportunity to meet Robert Bunsen, Gustav Kirchhoff, and other notable scientists. Because his weak lungs were bothered by the noxious fumes of sulfur compounds in Bunsen’s laboratory, Mendeleyev set up a private laboratory to work on his doctoral thesis on the combination of alcohol and water. In the course of his research at Heidelberg, he discovered that for every liquid there existed a temperature above which it could no longer be condensed from the gas to the liquid form. He called this temperature the absolute boiling point (this phenomenon was rediscovered a decade later by the Irish scientist Thomas Andrews, who called it the “critical temperature,” its modern descriptor). In September, 1860, Mendeleyev attended the Chemical Congress at Karlsruhe, Germany, and met the Italian chemistStanislao Cannizzaro, whose insistence on the distinction between atomic and molecular weights and whose system of corrected atomic weights had a great influence on him.

Upon his return to St. Petersburg, Mendeleyev resumed his lectures on organic chemistry. Because he lacked a permanent academic position, he decided to write a textbook on organic chemistry, which became a popular as well as a critical success. In 1863, he began to act as a consultant for a small oil refinery in Baku. In this same year he was married to Fezova Nikitichna Leshcheva, largely because one of his sisters insisted that he needed a wife. The couple had two children, a boy, Vladimir, and a girl, Olga. The marriage was not happy, however, and quarrels were frequent. Eventually, Mendeleyev and his wife separated. He continued to live in their St. Petersburg quarters, while his wife and children lived at their country estate of Boblovo. In 1864, Mendeleyev agreed to serve as professor of chemistry at the St. Petersburg Technical Institute while continuing to teach at the university. A year later, he defended his doctoral thesis on alcohol and water, arguing that solutions are chemical compounds indistinguishable from other types of chemical combination.

A turning point in Mendeleyev’s career occurred in October, 1865, when he was appointed to the chair of chemistry at the University of St. Petersburg. While teaching an inorganic-chemistry course there, he felt the need to bring to this subject the same degree of order that had characterized his earlier teaching of organic chemistry. Because he could find no suitable textbook, he decided to write his own. The composing of this book, eventually published as Osnovy khimii (1868-1871; The Principles of Chemistry , 1891), led him to formulate the periodic law. It was also one of the most unusual textbooks ever written. Unlike most textbooks, it was not a recycling of traditional material. It had instead a novel organization and an abundance of original ideas. It was also a curious blend of objective information and personal comment in which footnotes often took up more space than the text.

In organizing his ideas for the book, Mendeleyev prepared individual cards for all sixty-three elements then known, listing their atomic weights and properties, which showed great dissimilarities. For example, oxygen and chlorine were gases, whereas mercury and bromine were liquids. Platinum was very hard, whereas sodium was very soft. Some elements combined with one atom, others with two, and still others with three or four. In a search for order, Mendeleyev arranged the elements in a sequence of increasing atomic weights. By moving the cards around, he found that he could group certain elements together in already familiar families. For example, in the first table that he developed in March of 1869, lithium, sodium, potassium, and the other so-called alkali metals formed a horizontal row. In some groups he left empty spaces so that the next element would be in its proper family.

Mendeleyev’s analysis of his first arrangement convinced him that there must be a functional relationship between the individual properties of the elements and their atomic weights. One of the many interesting relationships he noticed concerned valence, the ability of an element to combine in specific proportions with other elements. He observed a periodic rise and fall of valence—1, 2, 3, 4, 3, 2, 1—in several parts of his arrangement. Because valence and other properties of the elements exhibited periodic repetitions, he called his arrangement in 1869 the periodic table . At the same time he formulated the periodic law: Elements organized according to their atomic weights manifest a clear periodicity of properties. He had been thinking about information relevant to the periodic law for fifteen years, but he formulated it in a single day. Mendeleyev would spend the next three years perfecting it, and in important ways he would be concerned with its finer points until his death.

When Mendeleyev’s paper was read by a friend at the Russian Chemical Society meeting in 1869, the periodic table did not evoke unusual interest. Its publication in German met with a cool reception. Mendeleyev’s opponents, who were especially censorious in England and Germany, were suspicious of highly imaginative theoretical schemes of the elements; many scientists before Mendeleyev had proposed such systems, which resulted in little of practical benefit for chemists.

Mendeleyev believed that if he could convince scientists of the usefulness of his system, it would attract followers. Therefore, he tried to show how his table and periodic law could be used to correct erroneously determined atomic weights. More significant, he proposed in an 1871 paper that gaps in his table could be used to discover new elements. In particular, he predicted in great detail the physical and chemical properties of three elements, which he called eka-aluminum, eka-boron, and eka-silicon, after the Sanskrit word for “one” and the name of the element above the gap in the table.

Mendeleyev’s predictions were met with great skepticism, but when, in 1875, Paul Lecoq de Boisbaudran discovered eka-aluminum in a zinc ore from the Pyrenees, skepticism declined, especially after chemists learned that the element’s characteristics had been accurately foretold by Mendeleyev. When, in 1879, Lars Nilson isolated eka-boron from the ore euxenite, even fewer skeptics were to be found. Finally, in 1879, when Clemens Winkler in Germany found an element in the ore argyrodite that precisely matched Mendeleyev’s predictions for eka-silicon, skepticism vanished. In fact, Winkler used Mendeleyev’s predictions of a gray element with an atomic weight of about 72 and a density of 5.5 in his search (he found a grayish-white substance with an atomic weight of 72.3 and a density of 5.5). These new elements were given the names gallium (1875), scandium (1879), and germanium (1886), and their discovery led to the universal acceptance of Mendeleyev’s periodic law.

In addition to campaigning for his periodic system, Mendeleyev during the 1870’s spent time on his technological interests. He was a patriot who wanted to see such Russian resources as coal, oil, salt, and metals developed properly. With this in mind, he visited the United States in 1876 to study the Pennsylvania oil fields. He was critical of the American developers’ concentration on the expansion of production while ignoring the scientific improvement of industrial efficiency and product quality. Upon his return to Russia, he was sent to study his country’s oil fields, and he became critical of the way they were exploited by foreign companies. He urged Russian officials to develop native oil for the country’s own benefit. From his experience in the oil fields, Mendeleyev developed a theory of the inorganic origin of petroleum and a belief in protective tariffs for natural resources.

In the year of his American trip, Mendeleyev underwent a domestic crisis. At a sister’s home he had met Anna Ivanovna Popov, a seventeen-year-old art student, and fallen desperately in love with her. Anna’s family opposed the relationship and made several attempts to separate the pair, resorting finally to sending her to Rome to continue her art studies. Mendeleyev soon followed her, leaving behind a message that if he could not wed her, he would commit suicide. She was mesmerized by this passionate man who, with his deep-set eyes and patriarchal beard, looked like a biblical prophet. She agreed to return to Russia and wed him, but the couple discovered that, according to the laws of the Russian Orthodox Church, Mendeleyev could not be remarried until seven years after his divorce.

Mendeleyev eventually found a priest who was willing to ignore the rule, but two days after the marriage the priest was dismissed and Mendeleyev was officially proclaimed a bigamist. Despite the religious crisis, nothing happened to Mendeleyev or his young wife. As the czar told a nobleman who complained about the situation: “Mendeleyev has two wives, yes, but I have only one Mendeleyev.” The second marriage proved to be a happy one, and the couple had two sons and two daughters. Anna Ivanovna introduced her husband to art, and he became an accomplished critic and an astute collector of paintings.

During the 1880’s and 1890’s, Mendeleyev became increasingly involved in academic politics. Ultimately, conflict with the minister of education prompted him to resign from the University of St. Petersburg. At his last lecture at the university, where he had taught for more than thirty years, the students gave him an enthusiastic ovation. His teaching career at an end, Mendeleyev turned to public service, where he was active in many areas.

When the Russo-Japanese War broke out in February, 1904, Mendeleyev became a strong supporter of his country’s efforts, and Russia’s defeat disheartened him. By this time, Mendeleyev was not only the grand man of Russian chemistry but also, because of the triumph of the periodic law, a world figure. In 1906, he was considered for a Nobel Prize, but the chemistry committee’s recommendation was defeated by a single vote, mainly because his discovery of the periodic law was more than thirty-five years old. Though he missed winning the Nobel Prize, he was showered with many awards in Russia and in many foreign countries. His end came early in 1907, when he caught a cold that developed into pneumonia. His chief consolation during his final illness was the reading of A Journey to the North Pole (Les Anglais au pôle nord, 1864; English translation, 1874) by Jules Verne, his favorite author.

Significance

Dmitry Ivanovich Mendeleyev’s name has become inextricably linked with the periodic table, but he was not the first to attempt to develop a systematic classification of the chemical elements. Earlier in the century, Johann Döbereiner, a German chemist, had arranged several elements into triads—for example, calcium, strontium, and barium—in which such properties as atomic weight, color, and reactivity seemed to form a predictable gradation. John Newlands, an English chemist, arranged the elements in the order of atomic weights in 1864 and found that properties seemed to repeat themselves after an interval of seven elements.

In 1866, Mendeleyev announced his “law of octaves,” in which he saw an analogy between the grouping of elements and the musical octave. Several other attempts at a systematic arrangement of the elements were made before Mendeleyev, some of which were known to him. Many scholars credit the German chemist Lothar Meyer as an independent discoverer of the periodic law, since in 1864 he published a table of elements arranged horizontally so that analogous elements appeared under one another.

Other scholars contend that Mendeleyev’s table was more firmly based on chemical properties than Meyer’s and it could be generalized more easily. Furthermore, Mendeleyev was a much bolder theoretician than Meyer. For example, he proposed that some atomic weights must be incorrect because their measured weight caused them to be placed in the wrong group of the table (Meyer was reluctant to take this step). In most instances Mendeleyev’s proposals proved to be correct (although the troublesome case of iodine and tellurium was not resolved until the discovery of isotopes). Finally and most notably, Mendeleyev was so impressed with the periodicity of the elements that he took the risk of predicting the chemical and physical properties of the unknown elements in the blank places of his table. Although his table had imperfections, it did bring similar elements together and help make chemistry a rational science and the periodic law an essential part of chemistry.

The periodic table grew out of the theoretical side of Mendeleyev’s scientific personality, but he also had a practical side. He made important contributions to the Russian oil, coal, and sodium-carbonate industries. He served the czarist regime in several official positions. Nevertheless, he did not hesitate to speak out against the government’s oppression of students, and his sympathy for the common people led him to travel third-class on trains. Though he held decidedly liberal views, it is wrong to see him as a political radical. Perhaps he is best described as a progressive, because he hoped that the czarist government would correct itself and evolve into a more compassionate regime.

Had Mendeleyev lived a few more years, he would have witnessed the complete and final development of his periodic table by Henry Moseley, whose discovery of atomic number by interacting X rays with various elements led to the use of the positive charge of the nucleus as the true measure of an element’s place in the periodic table. Throughout the twentieth century, the periodic table, which owed so much to Mendeleyev, continued to be enlarged by the discovery of new elements. It was therefore appropriate that a new element (atomic number 101), discovered in 1955, was named mendelevium, in belated recognition of the importance of his periodic law.

Bibliography

Farber, Eduard, ed. Great Chemists. New York: John Wiley & Sons, 1961. This collection of more than one hundred biographies of chemists contains an excellent short biography of Mendeleyev. Nontechnical and contains ample references to both primary and secondary literature.

Gordin, Michael D. A Well-ordered Thing: Dmitri Mendeleev and the Shadow of the Periodic Table. New York: Basic Books, 2004. Biography focusing on Mendeleyev’s professional years. Gordin recounts how Mendeleyev used his periodic table as a means of garnering attention for himself and as a platform for social change in imperial Russia.

Ihde, Aaron J. The Development of Modern Chemistry. New York: Harper & Row, 1964. Ihde traces the development of chemistry largely through its disciplines, for example, inorganic chemistry, organic chemistry, physical chemistry, and the like. Discusses Mendeleyev’s life and work in a chapter on the classification of elements. Contains an excellent and extensive annotated bibliography.

Jaffe, Bernard. Crucibles: The Lives and Achievements of the Great Chemists. New York: Simon & Schuster, 1930. This book tells the story of chemistry through the lives of some of its greatest practitioners. The approach is popular, uncritical, and accessible to young readers and those with little knowledge of chemistry. The chapter on Mendeleyev contains a good basic treatment of his life and his discovery of the periodic law.

Strathern, Paul. Mendeleyev’s Dream: The Quest for the Elements. London: Hamish Hamilton, 2000. A popular, accessible history of chemistry, describing the work of scientists from ancient Greece through the nineteenth century. As the title suggests, the book describes how Mendeleyev conceived of the periodic table in a dream, and details his contributions to the development of chemistry.

Van Spronsen, Johannes W. The Periodic System of Chemical Elements: A History of the First Hundred Years. Amsterdam: Elsevier, 1969. Several books have been written about the periodic system of chemical elements and its history, but this one, written to commemorate the hundredth anniversary of the periodic system, is the best. Van Spronsen analyzes Mendeleyev’s achievement in great detail. Based on original sources, the book requires some knowledge of chemistry for a full understanding of the analysis. Generously illustrated with diagrams, photographs, and graphs.

Weeks, Mary Elvira. Discovery of the Elements. Edited by Henry Leicester. 7th ed. Easton, Pa.: Journal of Chemical Education, 1968. This book, which has served chemists as a rich source of information about the elements—chemical, technical, historical, and biographical—has been made even more valuable by this new edition prepared by Leicester. The material on Russian chemists, including Mendeleyev, has been expanded. Extensively illustrated and thoroughly understandable to readers with a modicum of chemical knowledge.