What is Kekule in chemistry?
Kekule structure: A Lewis structure in which bonded electron pairs in covalent bonds are shown as lines. The most famous Kekule structures are what we would now call the two most significant resonance contributors of benzene. Adding lone pairs converts a Kekule structure into a Lewis structure.
What are the objections of Kekule formula?
Answer: Kekule’s structure does not explain the extra ordinary stable nature of benzene molecule and its lack of reactivity towards addition reactions, resistance towards oxidation etc. (iii) Equivalence of all the carbon-carbon bond lengths in benzene.
Why is Kekule structure wrong?
In benzene, all of the carbon-carbon bond lengths are equal. Therefore, the Kekule structure shown below is an incorrect representation of benzene. It is incorrect because it suggests that there are two different types of carbon-carbon bonds in benzene, a carbon-carbon double bond and a carbon-carbon single bond.
What did Kekule discover?
Kekule is regarded as one of the principal founders of modern organic chemistry, the chemistry of carbon-based compounds. In 1858 he showed that carbon can link with itself to form long chains. In 1865 he reported his discovery of the benzene ring as the basis for another major group of carbon molecules.
What is molecular formula of benzene?
C6H6
Benzene/Formula
Benzene is an organic chemical compound with the molecular formula C6H6. The benzene molecule is composed of six carbon atoms joined in a planar ring with one hydrogen atom attached to each.
What is Kekule structure of benzene?
In 1865, Kekule suggested a ring structure for benzene which consisted of a cyclic planar structure of six carbons having alternate double and single bonds. Each of the six carbons was attached to one hydrogen. (i) Benzene contains three double bonds. (ii) All the carbon and hydrogen atoms in benzene are equivalent.
What is resonance in benzene?
Resonance in benzene: Benzene ring has three double bonds in it and is expected to be quite reactive. Due to resonance in benzene, the carbon-carbon bonds in benzene acquire an intermediate character of carbon-carbon single and double bonds.
Is Kekule a Nobel Prize winner?
Of the first five Nobel Prizes in Chemistry, Kekulé’s former students won three: van ‘t Hoff in 1901, Fischer in 1902 and Baeyer in 1905. A larger-than-life monument of Kekulé, unveiled in 1903, is situated in front of the former Chemical Institute (completed 1868) at the University of Bonn.
Who discovered aromaticity?
An explanation for the exceptional stability of benzene is conventionally attributed to Sir Robert Robinson, who was apparently the first (in 1925) to coin the term aromatic sextet as a group of six electrons that resists disruption.