Conrad Laar

{{Short description|German chemist (1853–1929)}}

{{Use dmy dates|date=April 2016}}

{{Infobox scientist

|name = Conrad Laar

|image = Laar-conrad-peter-in-trommsdorff-paul-der-lehrkoerper-der-TH-hannover-1831-1931-hannover-1931-s024.jpg

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|birth_date = {{birth date|df=y|1853|03|22}}

|birth_place = Hamburg, Germany

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|nationality = German

|death_date = {{death date and age|df=y|1929|02|11|1853|03|22}}

|death_place = Bonn Germany

|field =

|work_institution = Universität Bonn

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|known_for = coining the expression tautomerism

|prizes = Nobel prize

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Conrad Peter Laar (22 March 1853 – 11 February 1929) was a German chemist.{{cite journal | doi = 10.1002/ange.19290424902 | title = Conrad Laar (1853 - 1929) | author = Pfeiffer | journal = Angewandte Chemie | volume = 42 | issue = 49 | page = 1117 | year = 1929| doi-access = free | bibcode = 1929AngCh..42.1117P }} He coined the term tautomerism in 1885.{{cite journal | doi =10.1002/cber.188501801141 | title =Ueber die Möglichkeit mehrerer Strukturformeln für dieselbe chemische Verbindung | year =1885 | last1 =Laar | first1 =Conrad | journal =Berichte der Deutschen Chemischen Gesellschaft | volume =18 | pages =648–657| url =https://zenodo.org/record/1425381 }} He also observed the double bond rule in 1885, which would later be formally postulated by Otto Schmidt.{{Cite journal|doi = 10.1021/ed075p596|title = A History of the Double-Bond Rule|year = 1998|last1 = Hoogenboom|first1 = Bernard E.|journal = Journal of Chemical Education|volume = 75|issue = 5|page = 596|bibcode = 1998JChEd..75..596H}}