Kekuld, August

Kekuld von Stradonitz, August 31 fin Kirchhoff, Gustav Robert 93n Kronecker, Leopold 7 In... 

In the mid-nineteenth century three individuals, working independently, laid the conceptual foundations for the structural theory of matter. August Kekuld, Archibald Scott Couper, and Alexander M. Butlerov each suggested that substances are defined by a specific arrangement of atoms. As an example, consider the structures of ammonium cyanate and urea from Wohler s experiment ... 

In benzene, each carbon atom uses three valence electrons to bond to the hydrogen atom and two adjacent carbons. That leaves one valence electron, which scientists first thought was shared in a double bond with an adjacent carbon. In 1865, August Kekuld proposed that the carbon atoms in benzene were arranged in a flat ring with alternating single and double bonds between the carbon atoms. There are two possible structural representations of benzene due to resonance in which the donble bonds can form between two different carbon atoms. 

Professor F. August Kekuld von Stradonitz (1829-1896), University of Bonn, Germany. 

Professor Michael Faraday (1791-1867), Royal Institute of Chemistry, London. Professor F. August Kekuld see Section 1-4. 

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