- Ludwig Wilhelmy
Ludwig Ferdinand Wilhelmy (
1812 –1864 ) was a German scientist who is usually credited with publishing the first quantitative study inchemical kinetics . [cite book | last = Laidler | first = Keith | title = The World of Physical Chemistry | publisher = Oxford | year = 1993 | page = 232 ] [cite book | last = Jones | first = Harry | title = The Elements of Physical Chemistry | publisher = Macmillan | year = 1903 | page = 444 ]Scientific work
Wilhelmy studied at Heidelberg, earning a doctorate in 1846. He worked as a
Privatdozent from 1849 to 1854 before moving to Berlin.Wilhelmy's work in chemical kinetics concerned the acid-catalyzed conversion of a
sucrose solution into a 1:1 mixture offructose andglucose , a reaction that he followed with apolarimeter . He wrote a differential equation to describe the reaction, integrated it, and used it to interpret his experimental results. [cite journal | author = Wilhelmy, Ludwig | title = Ueber das Gesetz, nach welchem die Einwirkung der Säuren auf den Rohrzucker stattfindet (The Law By Which the Action of Acids on Cane Sugar Occurs) | journal = Poggendorff's Annalen der Physik und Chemie | year = 1850 | volume = 81 | pages = 413 – 433 | url =http://gallica.bnf.fr/ark:/12148/bpt6k15166k/f427.table] Wilhelmy found that the reaction's rate was proportional to the concentrations of sucrose and of acid present. He also examined the influence of temperature on the reaction.According to Moore, Wilhelmy received little credit from his contemporaries for his early investigations in the field of chemical kinetics. [cite book | last = Moore | first = F. J. | title = A History of Chemistry | publisher = McGraw-Hill | year = 1931 | page = 256 ] It has been speculated that the strong physical-chemical orientation of Wilhelmy's work, the new method of
polarimetry , and the fact that Wilhelmy was relatively unknown all led to this situation. Similar laboratory results were published byJacobus Henricus van 't Hoff andSvante Arrhenius 30 years later, with a much greater impact. [cite journal | last = Kritsman | first = Viktor A. | title = Ludwig Wilhelmy, Jacobus H. van't Hoff, Svante Arrhenius und die Geschichte der chemischen Kinetik | journal = Chemie in unserer Zeit | year = 1997 | volume = 31 | issue = 6 | pages = 269 – 327 | doi = 10.1002/ciuz.19970310605(Subscription required for electronic access)]Wilhelmy is also known for the
Wilhelmy plate method for measuring surface tensions.See also
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Chemical kinetics
*Wilhelmy plate Notes and references
Further reading
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* [http://web.lemoyne.edu/~giunta/wilhelmy.html Excerpts from Wilhelmy's 1850 paper]
External links
* [http://nobelprize.org/nobel_prizes/chemistry/laureates/1909/ostwald-lecture.html Nobel lecture of Wilhelm Ostwald] - describes and pays tribute to Wilhelmy's early work
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