Tiêu đề 2. CHEM OLY VOL-4 GOC-PART-II C W 89 to 151.pdf ✅

IX -Chemistry (Vol– IV) 89 Narayana Group of Schools Olympiad Class Work Book General Organic Chemistry - 2 ELECTRON DISPLACEMENT IN COVALENT BOND Inductive effect Resonance Mesomeric effect Electromeric effect Hyper conjugation Inductomeric effect CONCEPT FLOW CHART
IX -Chemistry (Vol – IV 90 Narayana Group of Schools Olympiad Class Work Book August Kekule 1829 - 1896 Kekule never used his first given name; he was known throughout his life as August Kekule. After he was ennobled by the Kaiser in 1895, he adopted the name August Kekule von Stradonitz, without the French acute accent over the second “e”. The French accent had apparently been added to the name by Kekules father during the Napoleonic occupation of Hesse by France, to ensure that French-speaking people pronounced the third syllable In 1856 Kekule became Privatdozent at the University of Heidelberg. In 1858 he was hired as full professor at the University of Ghent, then in 1867 he was called to Bonn, where he remained for the rest of his career. Basing his ideas on those of predecessors such General Orgnanic Chemistry - Part - 2 as Williamson, Edward Frankland, William Odling, Auguste Laurent, Charles- Adolphe Wurtz and others, Kekulé was the principal formulator of the theory of chemical structure (1857–58).This theory proceeds from the idea of atomic valence, especially the tetravalence of carbon (which Kekulé announced late in 1857) and the ability of carbon atoms to link to each other (announced in a paper published in May 1858), to the determination of the bonding order of all of the atoms in a molecule. Archibald Scott Couper independently arrived at the idea of self-linking of carbon atoms (his paper appeared in June 1858), and provided the first molecular formulas where lines symbolize bonds connecting the atoms. For organic chemists, the theory of structure provided dramatic new clarity of understanding, and a reliable guide to both analytic and especially synthetic work. As a consequence, the field of organic chemistry developed explosively from this point. Among those who were most active in pursuing early structural investigations were, in addition to Kekulé and Couper, Frankland, Wurtz, Alexander Crum Brown, Emil Erlenmeyer, and Alexander Butlerov