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Mendeleev,
Dmitri Ivanovich Russian chemist Born: Tobol'sk, Siberia, February 7, 1834 Died: St. Petersburg (now Leningrad), February 2, 1907 | |||||||||
Arrhenius Berzelius Bunsen Cannizzaro Curie Dalton Kekule Lavoisier Lecoq De Boisbaudran Mendeleev |
Mendeleev came of a large family of about fourteen to seventeen children, the records are not exactly clear. Dmitri was the youngest child. He may have had some Asian ancestry through his part Mongol mother. His grandfather brought the first printing press to Siberia and published the first newspaper. His father was principal of the local high school. Blindness ended his fathers career when Mendeleev was still very young. His mother began a glass factory to make ends meet and Mendeleev was tutored in science by a political prisoner, sent to Siberia. In 1849, his father died and his mothers glass factory burned down. They moved to Moscow where his mother was unable to get him into a college. She went on to St Petersburg, where she convinced an old friend of his dead father to use his influence. She died soon after. Mendeleev finished top of his class, then went to France and Germany for graduate training. He worked with Bunsen, and attended the great Karlsruhe Congress where he heard Cannizzaro express his views on atomic weight. He returned to St Petersburg and in 1866 became a professor of chemistry at the university. He became one of the most capable and interesting lecturers in Europe. Between 1868 and 1870 he wrote a chemistry textbook called The Principles of Chemistry that was probably the best chemistry book ever written in Russian and certainly one the most unusual. It had numerous footnotes that took up almost as much space as the book itself. With Cannizzaros theory of atomic weights firmly in his mind, Mendeleev began to arrange the elements in order of atomic weights. He immediately noticed an interesting thing in connection with the valence of the elements, the concept of which had been worked out years earlier by Frankland. The second element in his list was lithium. It had a valence of 1; that is an atom of lithium could combine with only one other atom. The next element was beryllium; it had a valence of 2. Next was boron with 3 and then carbon with a valence of 4. In fact, the order went 1,2,3,4,3,2,1. Mendeleev could arrange all the elements known in his time (sixty-three of them) in order of atomic weights and get periodic rises and falls of valence. He could also arrange them in rows, so that the elements of similar valence would fall into vertical columns. These elements also showed similar chemical properties. Mendeleev published his first periodic table in 1869, leaving gaps for the undiscovered elements, but it was received with general skepticism. Mendeleev picked three gaps and described the properties the missing elements should have. In 1875, de Boisbaudran discovered an element which matched to the last property, his prediction. More elements were subsequently discovered and Mendeleev was vindicated in the most dramatic way. He suddenly became the most famous chemist in the world. The Royal Society awarded him the Davy medal in 1882 and other honors were heaped upon him. He was sent on a mission to the United States where he studied the oilfields of Pennsylvania in order to advise the Russians concerning the development of the Caucasian oilfields. In 1905 his textbook was translated into English. Mendeleev was a decided liberal in his views and never feared speaking out against the Russian government oppression of students. His sympathy for the common people led him to travel third-class on trains to be with them. In 1906, just a few months before his death, he was almost awarded the Nobel Prize in chemistry, Moissan was chosen by one vote. In 1955, a newly discovered element (number 101) was named mendelivium, in recognition of his achievments. | |||||||||
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