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Dmitri Mendeleev. Periodicity. Dmitri Mendeleev. LIFE. Early Life. Dmitri Ivanovich Mendeleev 8 February 1834 Born in the village of Verkhnie Aremzyani Went to St. Petersburg where he entered the Main Pedagogical Institute in 1850
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Dmitri Mendeleev Periodicity
Dmitri Mendeleev LIFE
Early Life • Dmitri Ivanovich Mendeleev • 8 February 1834 • Born in the village of VerkhnieAremzyani • Went to St. Petersburg where he entered the Main Pedagogical Institute in 1850 • Became a science master of the Simferopol gymnasium №1 in 1855
Saint Petersburg • Became a professor at the Saint Petersburg Technological Institute and Saint Petersburg State University in 1864 and 1865 • Awarded Doctor of Science in 1865 for research on combinations of water in alcohol • Made Saint Petersburg a center for chemistry research • Received Copley Medal from the Royal Society of London • Resigned in 1890
Research and Later • Appointed Director of the Bureau of Weights and Measures in 1893 • Formulated new state standards for the production of vodka • Investigated composition of petroleum • Realized how important and useful it is for Russian • In 1905, Mendeleev was elected a member of the Royal Swedish Academy of Sciences • 1906 he was nominated to win Nobel Prize in Chemistry • Lost to Moissan because of corrupted panel who voted • Died in 1907 from influenza
Dmitri Mendeleev Periodic Table
Before Mendeleev • John Newlands published his Law of Octaves in 1865 • Lack of spaces for undiscovered elements • Placing two elements in one box • Not accepted • Did not predict new elements • Lothar Mayer published paper • Describing 28 elements • Did not predict new elements • In 1863 there were 56 known elements with a new element being discovered each year
Principles of Chemistry • Mendeleev wrote Principles of Chemistry which included his attempt at classifying the elements according to chemical properties through noticing patterns • Was unaware of work going on of periodic table by others • Made a table and added additional elements from the pattern • Made a formal presentation to the Russian Chemical Society, entitled “The Dependence between the Properties of the Atomic Weights of the Elements”, which described elements according to both atomic weight and valence.
“The Dependence between the Properties of the Atomic Weights of the Elements”, • Presentation stated: • Elements, if arranged according to their atomic weight, exhibit an apparent periodicity of properties • Elements which are similar in regards to their chemical properties have atomic weights which are either of nearly the same value or which increase regularly • The arrangement of the elements in groups of elements in the order of their atomic weights corresponds to their so-called valences, as well as, to some extent, to their distinctive chemical properties • The elements which are the most widely diffused have small atomic weights • The magnitude of the atomic weight determines the character of the element
We must expect the discovery of many yet unknown elements • The atomic weight of an element may sometimes be amended by a knowledge of those of its contiguous elements • Certain characteristic properties of elements can be foretold from their atomic weights
Mendeleev versus Meyer • Several months after the publishing of Mendeleev’s table, Meyer published a nearly identical table • Some consider Meyer and Mendeleev the co-creators of the periodic table • Most people agree that it was Mendeleev because of his accurate prediction of the qualities of the elements of what he called ekasilicon, ekaaluminium and ekaboron (germanium, gallium and scandium, respectively)
Predictions • Predicted eight new elements using Sanskrit prefixes for naming • Noted that tellurium has a higher atomic weight than iodine but placed them in the right order, incorrectly predicting that the accepted atomic weights at the time were at fault • Puzzled where to put lanthanides and predicted the existence of actinides • People dismissed his predictions of more elements until gallium and germanium were found and fit perfectly into their two missing spaces
The German abstract was the vehicle by which Mendeleev's ideas reached chemists working in Western Europe
In conclusion… • Successful chemist in all ways • Developed clearest, most consistent, and accurate periodic table of elements • Was able to make several testable predictions based on it • Still had errors that were fixed post-Mendeleev or by Mendeleev himself
Sculpture in honor of Mendeleev and the periodic table, located in Bratislava, Slovakia