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Chemistry Mendeleev

The person whose name is most closely associated with the periodic table is Dmitri Mendeleev (1836-1907), a Russian chemist. In writing a textbook of general chemistry, Mendeleev devoted separate chapters to families of elements with similar properties, including the alkali metals, the alkaline earth metals, and the halogens. Reflecting on the properties of these and other elements, he proposed in 1869 a primitive version of today s periodic table. Mendeleev shrewdly left empty spaces in his table for new elements yet to be discovered. Indeed, he predicted detailed properties for three such elements (scandium, gallium, and germanium). By 1886 all of these elements had been discovered and found to have properties very similar to those he had predicted. [Pg.33]

The periodic table of the elements proposed by Mendeleev in 1869 was one of the great landmarks in the development of chemistry. Mendeleev showed that when the elements that were known at that time were arranged in order of their atomic weights... [Pg.2]

Metallic gallium and its salts have little or no toxicity, compared to the very toxic thallium salts. The toxicity of the aluminum ion is controversial. The gallium ion has been investigated as a possible antitumor agent, but no clinically useful compounds have been produced, see also Inorganic Chemistry Mendeleev, Dimitri Semiconductors. [Pg.133]

Chemists were quick to appreciate Bohr s model because it provided an extremely clear and simple interpretation of chemistry. It explained the reason behind Mendeleev s table, that the position of each element in the table is nothing other than the number of electrons in the atom of the element, which, of course, represents an equal number of periodic changes in the nucleus. Each subsequent atom has one more electron, and the periodic valence changes reflect the successive filling of the orbital. Bohr s model also provided a simple basis for the electronic theory of valence. [Pg.32]

The concept of chemical periodicity is central to the study of inorganic chemistry. No other generalization rivals the periodic table of the elements in its ability to systematize and rationalize known chemical facts or to predict new ones and suggest fruitful areas for further study. Chemical periodicity and the periodic table now find their natural interpretation in the detailed electronic structure of the atom indeed, they played a major role at the turn of the century in elucidating the mysterious phenomena of radioactivity and the quantum effects which led ultimately to Bohr s theory of the hydrogen atom. Because of this central position it is perhaps not surprising that innumerable articles and books have been written on the subject since the seminal papers by Mendeleev in 1869, and some 700 forms of the periodic table (classified into 146 different types or subtypes) have been proposed. A brief historical survey of these developments is summarized in the Panel opposite. [Pg.20]

Indeed, the influence of Mendeleev s fruitful generalization pervades the whole modem approach to the chemistry of the elements. [Pg.31]

While still a student at the Academy, Ipatieffbegan to make a name for himself in the Russian chemical community as he began to publish some of his laboratory findings. His first professional milestone as a chemist came in 18h() when he joined Russia s Physical-Chemical Society. Here he came into close contact with Russia s most famous chemists, including Dimitri Mendeleev, discoverer of the periodic table and one of the founders ol the Society. In 1891, upon graduating from the school, he was appointed lecturer in chemistry at the Academy where he also continued to undertake original chemical research for his doctoral dissertation. In 1895, he was made assistant professor and, upon completion and acceptance of his dissertation in 1899, he became a full professor of chemistry. [Pg.679]

When Mendeleev first published his chart, there were 63 elements known. One year after his death, there were 86. The rapidity of this increase was made possible by the most important generalization of chemistry, the periodic table. [Pg.107]

Worrall had made similar claims regarding theories of light developed in the seventeenth century and in particular, the case of Fresnel whose dramatic and subsequently confirmed predictions had not been as influential as his accommodation of already known optical phenomena. Meanwhile, Stephen Brush had turned his attention to chemistry and the periodic table, given that this seemed to be a case for which successful predictions made by Mendeleev are widely held to have been the reason for the acceptance of the periodic... [Pg.6]

But this characterisation is difficult to reconcile with the historical record. Ihde, the only historian of chemistry quoted by either Maher or Lipton, identifies Mendeleev s famous paper of 1871 as the major turning-point ... [Pg.50]

After spending considerable time perusing the crumbling pages of late nineteenth-century chemistry journals and textbooks, I have confirmed the traditional account Mendeleev s periodic law attracted little attention. . . until chemists started to discover some of the elements needed to fill the gaps in his table and found that their properties were remarkably similar to those he had predicted. The frequency with which the periodic law was mentioned in-journals increased sharply after the discovery of gallium, most of that increase was clearly associated with Mendeleev s prediction of the properties of the new element, (p, 617)20... [Pg.66]

It is no surprise that Mendeleev never gave precise mathematical expression to this periodic function . In fact, it would be impossible, we claim, to state at all precisely the content of Mendeleev s periodic law . (We are, of course, referring here to the law as articulated by Mendeleev himself and as understood by his contemporaries. There is no doubt that the subsequent development of chemistry has seen at least great progress toward the articulation of a precise version of the periodic law, based ultimately on quantum mechanics.24)... [Pg.75]

Notice that the lack of specificity of the periodic law as then conceived does not entail that Mendeleev failed to operate in a precise way locally. For example, he himself gave a clear account of his approach to working out some of the main relationships between the properties of the elements in his textbook The Principles of Chemistry. The method consists of simultaneous interpolation within groups or columns as well as within periods or rows of the periodic table. The average of the values of the numerical properties of the four elements flanking the element in question are taken to determine the latter s properties. So Mendeleev wrote ... [Pg.75]

Mendeleev, D, I. (1891) The Principles of Chemistry, 1st English ed., trans. G. Kamensky (New York Collier). [Pg.89]

This year marks the 100th anniversary of the death of one of the most famous scientists of all time, the Russian chemist Dmitri Ivanovich Mendeleev (1834-1907). The periodic table that he introduced in 1869 was a monumental achievement— a wonderful mnemonic and a tool that serves to organize the whole of chemistry. No longer were students of chemistry obliged to memorize the properties of all the known elements hereafter they could leam the properties of at least one element from each column and could, in principle, make sound predictions about the other elements in the column. [Pg.112]

But the periodic system is so fundamental, pervasive and familiar in the study of chemistry that it is often taken for granted. A century after the death of the leading discoverer of the periodic system, the Russian chemist Dimitri Mendeleev, it seems time to revisit the origins and modem status of this now-standard chemical classification. There were a number of historic precursors to Mendeleev s periodic system. But there are also current ongoing debates regarding the best way to display the periodic system, and whether there is really a "best way" of doing so. [Pg.123]

On the other hand, if one considers all of Mandeleev s many predictions of new elements, his powers of prophecy appear somewhiit less impressive, even to the point of being a little worrying. In all Mendeleev predicted a total of 16 elements, of which only nine were subsequently Isolated. As one historian of chemistry has wondered, how b it that weareprcpaied to forgive Mendeleev so many failures ... [Pg.126]


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See also in sourсe #XX -- [ Pg.85 , Pg.86 ]

See also in sourсe #XX -- [ Pg.85 , Pg.86 ]




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Mendeleev

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