Editing Wilhelm Ostwald

{{Short description|German chemist and philosopher (1853–1932)}}
{{Use dmy dates|date=September 2022}}
{{Infobox scientist
| image             = Wilhelm Ostwald by Nicola Perscheid.jpg
| caption           = Photograph of Ostwald {{circa|1913}} 
| birth_name        = Wilhelm Friedrich Ostwald
| birth_date        = {{osd|2 September|1853|21 August}}
| birth_place       = [[Riga]], Governorate of Livonia, Russian Empire
| death_date        = {{death date and age|df=y|1932|4|4|1853|9|2}}
| death_place       = [[Großbothen]], Saxony, Weimar Republic
| alma_mater        = [[University of Dorpat]]
| known_for         = {{collapsible list|title={{nobold|''See list''}}|{{ubl|[[Physical chemistry#History|Founding of physical chemistry]]|[[Blood–gas partition coefficient|Ostwald coefficient]]|[[Ostwald color system]]|[[Ostwald dilution law]]|[[Ostwald process]]|[[Ostwald ripening]]|[[Ostwald's rule]]|[[Viscometer#U-tube viscometers|Ostwald viscometer]]|[[Ostwald–Freundlich equation]]|[[Pipette#Ostwald–Folin pipette|Ostwald–Folin pipette]]|[[Power-law fluid|Ostwald–de Waele relationship]]|[[Liesegang rings (geology)|Ostwald–Liesegang rings]]|[[Catalysis]]|[[Colligative properties]]|[[Energeticism]]|[[HSL and HSV]]|[[Mole (unit)#History|Coining the term ''mole'']]}}}}
| awards            = {{ubl|[[Faraday Lectureship Prize]] (1904)|[[Nobel Prize in Chemistry]] (1909)|[[Wilhelm Exner Medal]] (1923)}}
| fields            = [[Chemistry]]
| work_institutions = {{ubl|University of Dorpat|[[Riga Polytechnicum|Riga Polytechnical Institution]]|[[Leipzig University]]}}
| doctoral_students = {{ubl|[[Arthur Amos Noyes]]|[[Georg Bredig]]| [[Paul Walden]]|[[Frederick G. Donnan]]|[[Louis Albrecht Kahlenberg]]|[[James Walker (chemist)|James Walker]]|[[Willis Rodney Whitney]]}}
}}
'''Wilhelm Friedrich Ostwald''' ({{IPA|de|ˈvɪlhɛlm ˈɔstˌvalt|lang|De-Wilhelm Ostwald.ogg}}; {{OldStyleDate|2 September|1853|21 August}} – 4 April 1932) was a Latvian [[chemist]] and [[German philosophy|philosopher]].  Ostwald is credited with being one of the founders of the field of [[physical chemistry]], with [[Jacobus Henricus van 't Hoff]], [[Walther Nernst]] and [[Svante Arrhenius]].<ref name="Arrhenius SHI">{{cite web |title=Svante August Arrhenius |url=https://www.sciencehistory.org/historical-profile/svante-august-arrhenius |website=sciencehistory.org |date=June 2016 |publisher=Science History Institute |access-date=17 June 2020}}</ref>
He received the [[Nobel Prize in Chemistry]] in 1909 for his scientific contributions to the fields of [[catalysis]], [[chemical equilibria]] and [[Reaction velocity|reaction velocities]].<ref name="Nobel">{{cite web |title=Wilhelm Ostwald Biographical |url=https://www.nobelprize.org/prizes/chemistry/1909/ostwald/biographical/ |website=nobelprize.org |publisher=Nobel Media AB |access-date=17 June 2020}}</ref>

Following his 1906 retirement from academic life, Ostwald became much involved in philosophy, art, and politics. He made significant contributions to each of these fields.<ref name="Kim">{{cite journal |last1=Kim |first1=Mi Gyung |title=Wilhelm Ostwald (1853–1932) |journal=International Journal for Philosophy of Chemistry |date=2006 |volume=12 |issue=1 |page=141 |url=http://www.hyle.org/journal/issues/12-1/bio_kim.htm |access-date=8 August 2020}}</ref> He has been described as a [[polymath]].<ref name="Ostwald Park" />

==Early life and education==
Ostwald was born ethnically [[Baltic German]] in [[Riga]], Russian Empire (now [[Latvia]]) to [[cooper (profession)|master-cooper]] Gottfried Wilhelm Ostwald and Elisabeth Leuckel. He was the middle child of three, born after Eugen and before Gottfried.<ref name="Profiles"/> Ostwald developed an interest in science as a child and conducted experiments at his home, particularly related to fireworks and photography.<ref name="Ostwald Park" />

Ostwald entered the [[University of Dorpat]] (now the University of Tartu, Estonia) in 1872. He completed his ''Kandidatenschrift'' examinations there in 1875.<ref name="Nobel" /><ref name="Kim"/> During his time at Dorpat, Ostwald had significant exposure to the [[humanities]], the arts, and philosophy, which became a focus of his endeavors after his 1906 retirement from [[academia]].<ref name="Kim" />

== Academic career ==
Ostwald began his career as an independent unpaid investigator at the University of Dorpat in 1875. He worked in the laboratory of [[Carl Schmidt (chemist)|Carl Schmidt]], along with his contemporary Johann Lemberg.  Lemberg taught Ostwald many of the basics of the [[Qualitative inorganic analysis|analysis of inorganic compounds]] and measurements of [[Chemical equilibrium|equilibria]] and chemical [[reaction rates]]. Lemberg also taught Ostwald the chemical basis of many geologic phenomena. These endeavors formed part of the subjects of Ostwald's later research efforts.<ref name="Kim" />  In addition to his work in Carl Schmidt's laboratory, Ostwald also studied in the university's physics institute with [[Arthur von Oettingen]].<ref name="Nobel" />

Around 1877, still continuing his work as an unpaid investigator in the Chemistry Laboratory at the University of Dorpat, Ostwald became a paid assistant in the Physics Institute, after Oettingen's assistant moved to Riga.<ref name="Kim" /><ref name="Birthday">{{cite journal |title=Wilhelm Ostwald (To 150th Anniversary of His Birthday) |journal=Russian Journal of Applied Chemistry |date=October 2003 |volume=76 |issue=10 |pages=1705–1709 |doi=10.1023/B:RJAC.0000015745.68518.e9|s2cid=195240066 }}</ref> 
He also supported himself for a time by teaching mathematics and science at a Dorpat high school.<ref name="Bancroft">{{cite journal |last1=Bancroft |first1=Wilder D. |title=Wilhelm Ostwald, the great protagonist. Part I |journal=Journal of Chemical Education |date=September 1933 |volume=10 |issue=9 |pages=539 |doi=10.1021/ed010p539|bibcode=1933JChEd..10..539B }}</ref>

Ostwald was deeply interested in questions of [[chemical affinity]] and the reactions that formed [[chemical compounds]]. This was the central theoretical question facing chemists at the time. As part of his early work, Ostwald developed a three-dimensional affinity table that took into account the effects of temperature as well as the affinity constants of [[acids]] and [[Base (chemistry)|bases]].<ref name="Kim" /> Ostwald also investigated [[Law of mass action|mass action]], [[electrochemistry]], and [[chemical dynamics]].<ref name="Nobel" />

Ostwald completed his Magisterial degree at the University of Dorpat in 1877, enabling him to give lectures and charge for teaching.<ref name="Deltete">{{cite journal |last1=Deltete |first1=R. J. |title=Wilhelm Ostwald's Energetics 1: Origins and Motivations |journal=Foundations of Chemistry |date=1 March 2007 |volume=9 |issue=1 |pages=3–56 |doi=10.1007/s10698-005-6707-5|s2cid=95249997 }}</ref> 
Ostwald published his [[doctoral dissertation]] at the University of Dorpat in 1878, with Carl Schmidt as his [[thesis advisor]].  His [[doctoral thesis]] was entitled ''Volumchemische und Optisch-Chemische Studien'' ("Volumetric and Optical-Chemical Studies").<ref name="Ostwald Park" /> In 1879, he became a paid assistant to Carl Schmidt.<ref name="FamousScientists">{{cite web |last1=Stewart |first1=Doug |title=Wilhelm Ostwald |url=https://www.famousscientists.org/wilhelm-ostwald/ |website=famousscientists.org |access-date=14 August 2020}}</ref>

In 1881, Ostwald became a [[Professor of Chemistry]] at the [[Riga Polytechnicum]] (now Riga Technical University). In 1887, he moved to [[Leipzig University]] where he became Professor of Physical Chemistry.<ref name="Profiles">{{Cite book|title=Profiles in Excellence Nobel Laureates All: 1901–2015|publisher=Panther Publishers|year=2016|editor-last=Rajasekharan|editor-first=P.T.|location=Bangalore, India|chapter=Ostwald, Wilhelm|editor-last2=Tiwari|editor-first2=Arun| isbn=978-1-78539-859-9 | url=https://books.google.com/books?id=cfwQnQAACAAJ}}</ref> Ostwald remained on the faculty at Leipzig University until his retirement in 1906. He also served as the first "exchange professor" at [[Harvard University]] in 1904 and 1905.<ref name="Nobel" /><ref name="softschools">{{cite web |title=Wilhelm Ostwald Facts |url=https://www.softschools.com/facts/scientists/wilhelm_ostwald_facts/2019/ |website=softschools.com |publisher=Soft Schools |access-date=19 June 2020}}</ref>

During Ostwald's academic career, he had many research students who became accomplished scientists in their own right. These included future [[Nobel Laureates]] [[Svante Arrhenius]], [[Jacobus Henricus van 't Hoff]], and [[Walther Nernst]].
Other students included [[Arthur Amos Noyes|Arthur Noyes]], [[Willis Rodney Whitney]] and [[Kikunae Ikeda]]. All of these students became notable for their contributions to physical chemistry.<ref name="Nobel" /><ref>{{cite journal |last1=Iwamura |first1=H. |title=In Commemoration of the 150th Anniversary of the Department of Chemistry, School of Science, The University of Tokyo-Its Past and Future |journal=Chemistry: An Asian Journal |date=4 July 2011 |volume=6 |issue=7 |pages=1632–1635 |doi=10.1002/asia.201100323|pmid=21721109 |doi-access=free }}</ref>

In 1901, [[Albert Einstein]] applied for a research position in Ostwald's laboratory. This was four years before Einstein's publication on [[special relativity]]. Ostwald rejected Einstein's application, although later the two developed strong mutual respect.<ref name="Isaacson">{{cite news |last1=Isaacson |first1=Walter |title=20 Things You Need to Know About Einstein |url=https://content.time.com/time/specials/packages/article/0,28804,1936731_1936743_1936804,00.html |access-date=8 August 2020 |agency=[[Time Magazine]] |publisher=Time USA, LLC |date=5 April 2007|author1-link=Walter Isaacson }}</ref> Subsequently, Ostwald nominated Einstein for the [[Nobel Prize]] in 1910 and again in 1913.<ref name="Nominations">{{cite web |title=Wilhelm Ostwald – Nominations |url=https://www.nobelprize.org/prizes/chemistry/1909/ostwald/nominations/ |website=nobelprize.org |publisher=The Nobel Foundation |access-date=8 August 2020}}</ref>

Following his 1906 retirement, Ostwald became active in philosophy, politics, and other humanities.<ref name="Nobel" />

During the course of his academic career, Ostwald published more than 500 original research papers for the [[scientific literature]] and approximately 45 books.<ref name="FamousScientists" />

== Scientific contributions ==
=== Nitric acid process ===
Ostwald invented a process for the inexpensive manufacture of [[nitric acid]] by [[oxidation]] of [[ammonia]]. He was awarded patents for this process.<ref>W. Ostwald, "Process for Manufacturing Nitric Acid, [https://patentimages.storage.googleapis.com/93/97/63/d4b81eb9a5c399/US858904.pdf US858904], 2 July 1907.</ref> Ostwald's patent made use of a [[catalyst]] and described conditions under which the yield of nitric acid was near the [[Theoretical yield|theoretical limit]]. Aspects of the basic process had also been patented some 64 years earlier by [[Charles Frédéric Kuhlmann|Kuhlmann]].<ref>Note:

* Frédéric Kuhlmann, "Pour la fabrication de l'acide nitrique et des nitrates," French patent no. 11,331 (filed:  October 1838; issued:  22 December 1838).  Supplemental patent issued:  7 June 1839.  See:  ''Description des machines et procédés consignés dans les brevets d'invention,'' ... [Description of machines and methods recorded in the patents of invention, ... ] (Paris, France:  Madame Veuve Bouchard-Huzard, 1854), '''82''' :  [https://books.google.com/books?id=BppbAAAAcAAJ&pg=PA160 160.]
* Fréd. Kuhlmann (1838) [http://gallica.bnf.fr/ark:/12148/bpt6k29662/f1107.image.langEN "Note sur plusieurs réactions nouvelles déterminées par l'éponge de platine, et considérations sur les services que cette substance est appelée à rendre à la science"] (Note on several new reactions caused by platinum sponge, and reflections on the services that this substance is called to render to science), ''Comptes rendus'', '''7''' :  1107–1110.  From page 1109:  ''"1°. L'ammoniaque mêlée d'air en passant à une température de 300° environ sur de l'éponge de platine, est décomposée, et l'azote qu'il renferme est complétement transformé en acide nitrique, aux dépens de l'oxigène de l'air."'' (1. Ammonia mixed with air, upon passing at a temperature of about 300° over platinum sponge, is decomposed and the nitrogen that it contains is completely transformed into nitric acid, at the expense of the oxygen of the air.)
* John Graham Smith (1988)  "Frédéric Kuhlmann:  Pioneer of platinum as an industrial catalyst," ''Platinum Metals Review'', '''32''' (2) :  84–90.</ref> Kuhlmann's process did not become industrially significant, likely due to the lack of an inexpensive source of ammonia.  Shortly after Ostwald's finding, inexpensive ammonia became available as a result of [[Fritz Haber|Haber]] and [[Carl Bosch|Bosch's]] invention of a process for [[nitrogen fixation|nitrogen fixing]] [[Haber process|process]] (completed by 1911 or 1913) for ammonia synthesis. The combination of these two breakthroughs soon led to more economical and larger-scale production of [[fertilizer]]s and [[explosives]], of which Germany was in short supply during [[World War I]].<ref name="Haber process">{{cite web |last1=Louchheim |first1=Justin |title=Fertilizer History: The Haber-Bosch Process |url=https://www.tfi.org/the-feed/fertilizer-history-haber-bosch-process#:~:text=The%20solution%20soon%20came%20from,component%20in%20nitrogen%2Dbased%20fertilizers. |website=tfi.org |date=19 November 2014 |publisher=The Fertilizer Institute |access-date=16 June 2020}}</ref><ref name="Explosives">{{cite web |last1=Sutton |first1=Mike |title=Chemists at War |url=https://www.chemistryworld.com/features/chemists-at-war/7568.article#/ |website=chemistryworld.org |publisher=Royal Society of Chemistry |access-date=16 June 2020}}</ref> The process is often referred to as the [[Ostwald Process]].<ref name="Explosives" /> The process remains in widespread use in contemporary times for manufacture of nitric acid.<ref name="Catalysis" />
[[File:Van 't Hoff und Ostwald 01.jpg|left|thumb|300px|[[Jacobus Henricus van 't Hoff|Jacobus van 't Hoff]] (left) and Wilhelm Ostwald]]

=== Ostwald's dilution law===
Ostwald also conducted significant research on dilution theory leading to his conceptualization of the [[law of dilution]] which at times is referred to as "Ostwald's Dilution Law". This theory holds that the behavior of a [[weak electrolyte]] follows the [[Law of mass action|principles of mass action]], being extensively dissociated at infinite dilution. This characteristic of weak electrolytes can be observed experimentally, such as by [[Electrochemistry|electrochemical determinations]].<ref name="Dilution Law">{{cite web |title=Ostwald's Dilution Law |url=https://www.sciencehq.com/chemistry/ostwalds-dilution-law.html |website=sciencehq.com |publisher=Rod Pierce DipCE BEng |access-date=11 June 2021 |url-status=dead |archive-url=https://web.archive.org/web/20210214005845/http://www.sciencehq.com/chemistry/ostwalds-dilution-law.html |archive-date=14 February 2021}}</ref>

===Catalysis===
Through his research on chemical reaction rates and velocities and his studies of acids and bases, Ostwald found that the concentration of acid or the concentration of base in a solution of certain chemical reactants can have a strong influence of the rate of chemical processes. He realized that this is manifestation of the concept of chemical catalysis first articulated by [[Berzelius]]. Ostwald articulated the idea that a catalyst is a substance that accelerates the rate of a chemical reaction without being a part of either the reactants or the products. Ostwald's advances in the understanding of chemical catalysis were widely applicable in biological processes such as enzymatic catalysis and also in many industrial processes. A catalyst is used in the nitric acid process that Ostwald invented.<ref name="Catalysis">{{cite journal |last1=Van Houten |first1=J. |title=A Century of Chemical Dynamics Traced through the Nobel Prizes |journal=Journal of Chemical Education |date=2002 |volume=79 |issue=2 |page=146 |doi=10.1021/ed079p146 }}</ref>

=== Crystallization ===
Ostwald studied the [[crystallization]] behavior of solids, especially those solids that are capable of crystallizing in different forms, in the phenomenon known as [[Polymorphism (materials science)|polymorphism]]. He discovered that solids do not necessarily crystallize in their most thermodynamically stable form but instead sometimes crystallize preferentially in other forms dependent on the relative rates of crystallization of each polymorphic form. Ostwald found that the relative rates were dependent on the surface tension between the solid polymorph and the liquid form. Many common materials exhibit this type of behavior, including [[minerals]] and various [[organic compounds]]. This finding came to be known as [[Ostwald's rule]].<ref name="Ostwald Rule">{{cite thesis |last1=Wang |first1=Tingting |title=Breakdown of the Ostwald step rule – The precipitation of calcite and dolomite from seawater at 25 and 40 °C |date=2013 |url=https://escholarship.mcgill.ca/concern/theses/sn00b224t }}</ref>

Ostwald realized that solid or liquid solutions can continue to evolve over time. While the a non-thermodynamically preferred polymorph may crystallize first, more thermodynamically stable forms can continue to develop as the solution ages. Often this results in large crystals forming, since they are more thermodynamically stable than are large numbers of small crystals. This phenomenon came to be known as Ostwald Ripening and is observed in many situations. An everyday example is the gritty texture that ice cream develops as it ages. On a [[geologic timescale]], many [[minerals]] exhibit Ostwald Ripening as their crystal forms evolve as the mineral ages.<ref name="Clay Minerals">{{cite journal |last1=Jahren |first1=J.S. |title=Evidence of Ostwald Ripening Related Recrystallization of Diagenetic Chlorites From Reservoir Rocks Offshore Norway |journal=Clay Minerals |date=1991 |volume=26 |issue=2 |page=169 |doi=10.1180/claymin.1991.026.2.02 |bibcode=1991ClMin..26..169J |citeseerx=10.1.1.604.4580 |s2cid=97430142 }}</ref>

Related to solubility and crystallization was Ostwald's finding that dissolution of a solid depends on the size of the crystal. When the crystals are small, typically less than a [[micron]], the solubility of the solid in the solution phase is increased. Ostwald quantified this effect mathematically in a relationship that became known as the [[Ostwald-Freundlich equation]]. Ostwald first published his finding in 1900, and his mathematical equation was refined by German chemist [[Herbert Freundlich]] in 1909. This mathematical relationship also applies to the partial pressure of substance in the system. The Ostwald-Freundlich equation takes into account the surface tension of the particle in the system, in addition to curvature and temperature. The size dependence of solubility is sometimes utilized in the formulation of [[pharmaceuticals]] that have low solubility so as to enhance their uptake by the patient. The size dependence also has a role in Ostwald Ripening.<ref name="Freundlich eqn">{{cite journal |last1=Eslami |first1=Fatemeh |last2=Elliott |first2=Janet A. W. |title=Role of Precipitating Solute Curvature on Microdrops and Nanodrops during Concentrating Processes: The Nonideal Ostwald–Freundlich Equation |journal=Journal of Physical Chemistry B |date=2014 |volume=118 |issue=50 |pages=14675–86 |doi=10.1021/jp5063786 |pmid=25399753 |doi-access=free }}</ref>

[[File:Liesegang rings Saginaw Hill AZ.jpeg|left|thumb|Liesegang rings at Saginaw Hill, Arizona, USA]]
Collaborating with German chemist [[Raphael E. Liesegang]], Ostwald recognized that substances can crystallize in a periodic fashion wherein the crystallization behavior follows a spatial or temporal pattern. In certain circumstances, the result of this periodic crystallization behavior is easily visually observed, for example, in various [[geologic formations]]. Liesegang had previously investigated this phenomenon in specific laboratory experiments, showing his results to Ostwald. Ostwald then developed a mathematical model for the phenomenon that served to explain the observations and realized how widespread is the periodic crystallization behavior. These observations came to be known as [[Liesegang rings]].<ref name="Liesegang">{{cite web |title=A Short History of "Liesegang Rings" |url=https://www.insilico.hu/liesegang/history/history.html |website=insilico.hu |publisher=In Silico, Ltd. |access-date=7 August 2020}}</ref>

===Atomic theory===
[[File:Ostwald viscometer.jpg|thumb|Ostwald viscometer]]
Ostwald introduced the word [[Mole (unit)|mole]] into the [[lexicon]] of chemistry around 1900.  He defined one mole as the [[molecular weight]] of a substance in units of mass grams.  The concept was linked to the [[ideal gas]], according to Ostwald.  Ironically, Ostwald's development of the mole concept was directly related to his theory of [[energeticism]], in philosophical opposition to [[atomic theory]], against which he (along with [[Ernst Mach]]) was one of the last holdouts.  He explained in a conversation with [[Arnold Sommerfeld]] that he was convinced by [[Jean Perrin]]'s experiments on [[Brownian Motion|Brownian motion]].<ref>Nye, M., 1972, Molecular Reality: A Perspective on the Scientific Work of Jean Perrin, London: MacDonald.</ref><ref name="Gorin">{{cite journal |last1=Gorin |first1=George |title=Mole and Chemical Amount: A Discussion of the Fundamental Measurements of Chemistry |journal=Journal of Chemical Education |date=February 1994 |volume=71 |issue=2 |pages=114 |doi=10.1021/ed071p114|bibcode=1994JChEd..71..114G }}</ref>

In 1906 Ostwald was elected a member of the [[Commission on Isotopic Abundances and Atomic Weights|International Committee on Atomic Weights]]. As a consequence of [[World War I]], this membership ended in 1917 and was not resumed after the war.  The 1917 Annual Report of the committee ended with the unusual note: "Because of the European war the Committee has had much difficulty in the way of correspondence. The German member, Professor Ostwald, has not been heard from in connection with this report. Possibly the censorship of letters, either in Germany or en route, has led to a miscarriage".<ref name="Clark">{{cite journal | last=Clark | first=F.W. | year=1916 | title=Annual report of the international committee on atomic weights | journal=[[J. Am. Chem. Soc.]] | volume=38 | issue=11 | pages=2219–2221 | url=https://zenodo.org/record/1429080| doi=10.1021/ja02268a001}}</ref>

===Scientific measurements===
As part of Ostwald's investigations in to [[chemical equilibria]], [[chemical affinity]], and [[Acid-base balance|acid-base interactions]], he recognized that many established [[analytical methods]] disturb the chemical systems under investigation. He therefore turned to physical measurements as surrogate methods to understand these important basic phenomena. One such physical measurement is the measurement of the [[viscosity]], or resistance to flow, of a liquid. Ostwald invented a device for this purpose consisting of bulbs that act as reservoirs for a liquid with a capillary, or thin tube, in between the reservoirs.  The time that it takes for the liquid to flow through the capillary from one reservoir to the other is an indication of the viscosity of the liquid.  Using a reference solution, the viscosity of the liquid can be quantified. Ostwald typically used this device to study the behavior of [[solutes]] in water solutions. These devices came to be known as [[Ostwald viscometer]]s and are in widespread use in contemporary times for research and [[quality control]] purposes.<ref name="Sella">{{cite web |last1=Sella |first1=Andrea |title=Classic Kit: Ostwald's viscometer |url=https://www.chemistryworld.com/opinion/classic-kit-ostwalds-viscometer/3004929.article |website=chemistryworld.com |publisher=Royal Society of Chemistry |access-date=5 August 2020}}</ref>

Ostwald designed a pipette that could be used to transfer and measure liquids, especially [[serous fluid]]s. This design was later improved by [[Otto Folin]]. This type of pipette has a bulb at the lower end as a particular design feature. It became known as the [[Pipette#Ostwald–Folin pipette|Ostwald-Folin pipette]] and is widely used in contemporary times.<ref name="Pipette">{{cite web |title=Serological pipets |url=https://www.eppendorf.com/product-media/doc/en/308915/Liquid-Handling_Poster_Serological-Pipets.pdf |website=eppendorf.com |publisher=Eppendorf AG |access-date=11 August 2020}}</ref>

===Color science===
Following his 1906 retirement from academia, Ostwald became interested in the systematization of [[color]]s, which could be useful both scientifically and in the arts. He published ''The Color Primer'' and also ''The Color Atlas'' during the period of 1916–8. These publications established relationships between the various visual colors.<ref name="Ostwald Park" /> 
<gallery>
File:Die farbenfibel by Wilhelm Ostwald 1921 page 33.tif | ''The Color Primer'', <br/>page 33
File:Die farbenfibel by Wilhelm Ostwald 1921 page 44.tif | ''The Color Primer'', <br/>page 44
File:Die farbenfibel by Wilhelm Ostwald 1921 page 50.tif | ''The Color Primer'', <br/>page 50
File:Die farbenfibel by Wilhelm Ostwald 1921 page 56.tif | ''The Color Primer'', <br/>page 56
</gallery>

Ostwald represented these as a three dimensional representation of [[Ostwald color system|color space]] that is a [[Topological space|topological solid]] consisting of two cones.  One apex of the cone is pure white while the other is pure black. The eight primary colors are represented along the circumference or curved surfaces of the two cones. In this representation, each color is a mixture of white, black, and the eight primary colors. In this way, there are three [[degrees of freedom]] that represent each color.<ref name="Color science"/>

[[File:Ostwald Color.jpg|thumb|Ostwald color solid]]
This representation of colors was an important early step toward their systematization, replacing color perception by the human eye with an objective system.<ref name="Color science">{{cite web |last1=Nichols |first1=Kara |title=The Chemistry of Color |url=https://www.cooperhewitt.org/2018/05/09/the-chemistry-of-color/ |website=cooperhewitt.org |date=9 May 2018 |publisher=[[Smithsonian Design Museum]] |access-date=9 August 2020}}</ref> Much of Ostwald's work on systematization of color was done in collaboration with [[Deutscher Werkbund]], which was an association of painters and architects.<ref name="Kim" />

==Scholarly journals and societies==
In 1887, Ostwald founded the [[peer-reviewed scientific journal]] ''[[Zeitschrift für Physikalische Chemie]]'', specializing in original research in the field of physical chemistry.<ref name="Bancroft" /><ref name="Bhattacharyya">{{cite journal |last1=Bhattacharyya |first1=Pallavi |title=Wilhelm Ostwald – The Scientist |journal=Resonance |date=2012 |volume=May |issue=5 |pages=428–433 |doi=10.1007/s12045-012-0045-4 |s2cid=120420082 }}</ref> He served as its editor-in-chief until 1922. In 1894, Ostwald formed the German Electrochemical Society which ultimately became the Deutsche Bunsen-Gesellschaft für angewandte physikalische Chemie [German Bunsen-Society for Applied Physical Chemistry]. He created the journal ''[[Klassiker der exakten Wissenschaften]]'' in 1889, of which more than 250 volumes have been published.<ref name="Nobel" />

As part of his interest in philosophy, in 1902 Ostwald started the journal ''Annalen der Naturphilosophie'' (Annales of Natural Philosophy). In 1927, he initiated the journal ''Die Farbe'' (Colour).<ref name="Ostwald Park" />

Ostwald was one of the directors of the [[Die Brücke (institute)|Die Brücke]] institute in Munich, and he played a role in its founding in 1911. The institute was sponsored, significantly, from Ostwald's Nobel Prize money. Through the institute, Ostwald's intention was to develop a standardized system for scholarly publications.<ref name="Buckland2006">{{cite book|author=Michael Keeble Buckland|title=Emanuel Goldberg and his knowledge machine: information, invention, and political forces|url=https://books.google.com/books?id=QCddw5cVjVgC&pg=PA64|access-date=26 May 2011|date=April 2006|publisher=Greenwood Publishing Group|isbn=978-0-313-31332-5|page=64}}</ref> In 1911, Ostwald founded the Association of Chemical Societies, which sought to organize and improve the efficiency of various chemical societies. The association is an example of a [[scientific society]]. Ostwald served as the first president of the Association of Chemical Societies.<ref name="Kim" /><ref name="Nature 1912">{{cite journal |title=International Association of Chemical Societies |journal=Nature |date=9 May 1912 |volume=89 |issue=2219 |pages=245–246 |doi=10.1038/089245a0 |bibcode=1912Natur..89..245. |s2cid=3954721 |doi-access=free }}</ref>

== Scholarly contributions to humanities and politics ==
In addition to his research in chemistry, Wilhelm Ostwald was productive in a broad range of fields. His published work, which includes numerous philosophical writings, contains about forty thousand pages. Ostwald was also engaged in the [[peace movement]] of [[Berta von Suttner]].<ref name="Peace Movement">{{cite journal |last1=Chickering |first1=Roger
 |title=A Voice of Moderation in Imperial Germany: The "Verband fur internationale Verstandigung" 1911–1914
 |journal=Journal of Contemporary History |date=January 1973 |volume=8 |issue=1 |pages=147–164
 |doi=10.1177/002200947300800108
 |jstor=260073
 |s2cid=162389916
 }}</ref>

Among his other interests, Ostwald was a passionate amateur painter who made his own pigments.<ref name="Ball"/> He left more than 
1,000 paintings along with 3,000 pastels and color studies.<ref name="Root-Bernstein">{{cite journal |last1=Root-Bernstein |first1=Robert |title=Wilhelm Ostwald and the Science of Art |journal=Leonardo |date=October 2006 |volume=39 |issue=5 |pages=418–419 |doi=10.1162/leon.2006.39.5.418|s2cid=57561850 }}</ref> For Ostwald, science and the arts were mutually supportive areas of engagement.<ref name="Root-Bernstein"/>

{{blockquote|"Poetry, music and painting have given me refreshment and new courage, when exhausted by scientific work I have been obliged to lay my tools aside."–Ostwald<ref name="Root-Bernstein"/>}}

Ostwald regarded science and the arts as having a common aim, that of "coping with the infinite diversity of appearances through the formation of appropriate concepts"<ref name="Root-Bernstein"/>... Towards this aim, science builds "intellectual ideas; art constructs visual ones."<ref name="Root-Bernstein"/>

Ostwald developed a strong interest in [[color theory]] in the later decades of his life. He wrote several publications in the field, such as his ''Malerbriefe'' (''Letters to a Painter,'' 1904) and ''Die Farbenfibel'' (''The Color Primer,'' 1916). His work in color theory was influenced by that of [[Albert Henry Munsell]], and in turn influenced [[Piet Mondrian]] and other members of [[De Stijl]]<ref>John Gage, ''Color and Culture: Practice and Meaning from Antiquity to Abstraction'', Boston, Little, Brown and Co., 1993; pp. 247– 8, 257– 60.</ref>  and [[Paul Klee]] and other members of the [[Bauhaus school]].<ref name="Ball">{{cite journal |last1=Ball |first1=Philip |last2=Ruben |first2=Mario |title=Color Theory in Science and Art: Ostwald and the Bauhaus |journal=Angewandte Chemie International Edition |date=20 September 2004 |volume=43 |issue=37 |pages=4842–4847 |doi=10.1002/anie.200430086|pmid=15317016 }}</ref> Ostwald's theories also influenced Americans [[Faber Birren]] and [[Egbert Jacobson]].<ref name="Root-Bernstein"/>

He was also interested in the [[Universal language|international language]] movement, first learning [[Esperanto]], then later supporting [[Ido language|Ido]].  He was a member of a Committee of the [[Delegation for the Adoption of an International Auxiliary Language]].<ref name="Nye">{{cite journal|last1=Nye|first1=Mary Jo
 |title=Speaking in Tongues: Science's centuries-long hunt for a common language
 |journal=Distillations|date=2016|volume=2|issue=1|pages=40–43
 |url=https://www.sciencehistory.org/distillations/magazine/speaking-in-tongues|access-date=22 March 2018}}</ref><ref name="Gordin">{{cite book|last1=Gordin|first1=Michael D.
 |title=Scientific Babel: How Science Was Done Before and After Global English|date=2015
 |publisher=University of Chicago Press|location=Chicago, Illinois|isbn=9780226000299}}</ref><ref name="Forster">{{cite book |last1=Forster |first1=Peter Glover
 |title=The Esperanto Movement |date=1982 |publisher=Walter de Gruyter
 |url=https://books.google.com/books?id=5kNB5YmeNj4C&q=ostwald+esperantist+-wikipedia.org&pg=PA123|isbn=9789027933997 }}</ref> Ostwald donated half the proceedings of his 1909 Nobel prize to the Ido movement,<ref>{{Cite journal| last1 = Wall | first1 = F. E. | doi = 10.1021/ed025p2 | title = Wilhelm Ostwald | journal = Journal of Chemical Education | volume = 25 | issue = 1 | pages = 2–10 | year = 1948 | bibcode = 1948JChEd..25....2W }}</ref> funding the Ido magazine ''Progreso'' which he had proposed in 1908.<ref>{{cite web
|url=http://www.europa.idolinguo.com/Germania/Idokonfero2003/festdiskurso.htm
|title=L'agado di profesoro Wilhelm Ostwald por la LINGUO INTERNACIONA IDO
|last=Anton
|first=Günter
|language=io
|date=June 2003
|access-date=12 February 2012
}}</ref> Ostwald later went on to create his own language [[Weltdeutsch]] in a period of extreme nationalism during the First World War.

One of Ostwald's continuing interests was unification through systematization. In particular, Ostwald perceived that [[Efficient energy use|energy efficiency]] was a unifying theme in all facets of society and culture. In political matters, Ostwald's interest in energy efficiency extended to such political matters as the need for organization of labor.<ref name="Kim" />

Ostwald's interest in unification through systematization led to his adaptation of the philosophy of [[Monism]].<ref>{{cite book |last1=Görs |first1=Britta |last2=Psarros |first2=Nikolaos |last3=Ziche |first3=Paul |title=Wilhelm Ostwald at the Crossroads Between Chemistry, Philosophy and Media Culture |date=2005 |publisher=Leipziger Universitätsverlag |isbn=9783935693479 |url=https://books.google.com/books?id=6KnrWP-PEDsC |access-date=30 October 2020}}</ref> Initially, Monism was liberal, pacifist, and international, seeking in science a basis of values to support social and political reforms. Ostwald himself developed a system of ethics based on science, around the core idea that one should "not waste energy, but convert it into its most useful form."<ref name="Holt Monism"/><ref name="Hapke">{{cite journal |last1=Hapke |first1=Thomas |title=Wilhelm Ostwald's Combinatorics as a Link between In-formation and Form |journal=Library Trends |date=2012 |volume=61 |issue=2 |pages=286–303 |doi=10.1353/lib.2012.0041|s2cid=31027564 |url=http://tubdok.tub.tuhh.de/handle/11420/1097 }}</ref>

in 1911, Ostwald became President of the ''Deutscher Monistenbund'' (Monist Association), founded by [[Ernst Haeckel]].<ref>[[Andreas Daum|Andreas W. Daum]], ''Wissenschaftspopularisierung im 19. Jahrhundert: Bürgerliche Kultur, naturwissenschaftliche Bildung und die deutsche Öffentlichkeit, 1848–1914''. Munich: Oldenbourg, 1998, pp. 218, 505.</ref>  Ostwald (and other Monists) promoted [[eugenics]] and [[euthanasia]], but only as voluntary choices with the intention of preventing suffering. Monist promotion of such ideas is suggested to have indirectly facilitated acceptance of the later [[Social Darwinism]] of the [[National Socialists]]. Ostwald died before the Nazis adopted and enforced the use of eugenics and euthanasia as involuntary government policies, to support their racist ideological positions.<ref name="Holt Monism">{{cite journal |last1=Holt |first1=Niles R.
 |title=Monists & Nazis: A Question of Scientific Responsibility |journal=The Hastings Center Report |date=April 1975 |volume=5 |issue=2 |pages=37–43
 |doi=10.2307/3560820
 |jstor=3560820
 }}</ref><ref name="Kim"/>  Ostwald's Monism also influenced [[Carl G. Jung]]'s identification of psychological types.<ref>Noll, Richard, The Jung Cult. Princeton University Press, 1994, p. 50</ref>

==Honours and awards==
[[File:Nobel Prize certificate for Wilhelm Ostwald 1909 - Chemistry.jpg|thumb|Nobel Prize certificate for Wilhelm Ostwald]]
Ostwald was elected an International Honorary Member of the [[American Academy of Arts and Sciences]] in 1905 and an International Member of the United States [[National Academy of Sciences]] in 1906.<ref>{{Cite web |date=2023-02-09 |title=Wilhelm Ostwald |url=https://www.amacad.org/person/wilhelm-ostwald |access-date=2023-11-22 |website=American Academy of Arts & Sciences |language=en}}</ref><ref>{{Cite web |title=Wilhelm Ostwald |url=https://www.nasonline.org/member-directory/deceased-members/20001234.html |access-date=2023-11-22 |website=www.nasonline.org}}</ref> He received the 1909 Nobel Prize for Chemistry for his contributions to understanding catalysis and for his investigations of the fundamental principles underlying chemical equilibria and reaction rates. He was nominated for the Nobel Prize 20 times beginning in 1904, and he submitted nine nominations of other scientists for the Nobel Prize following his own award. This included two nominations of Albert Einstein.<ref name="Nominations" /> Ostwald donated more than US$40,000 of his Nobel Prize award money to advance the cause of the Ido language.<ref name="Gordin_p151">{{cite book |last1=Gordin |first1=Michael D. |title=Scientific Babel: How Science Was Done Before and After Global English |date=2015 |publisher=University of Chicago Press |isbn=9780226000329 |page=151}}</ref> He was elected an International Member of the [[American Philosophical Society]] in 1912.<ref>{{Cite web |title=APS Member History |url=https://search.amphilsoc.org/memhist/search?creator=Wilhelm+Ostwald&title=&subject=&subdiv=&mem=&year=&year-max=&dead=&keyword=&smode=advanced |access-date=2023-11-22 |website=search.amphilsoc.org}}</ref>

In 1923, Ostwald was awarded the [[Wilhelm Exner Medal]], which recognized the [[economic impact]] of Ostwald's scientific contributions.<ref name="Exner">{{cite web |title=Wilhelm Ostwald |url=https://www.wilhelmexner.org/medalists/wilhelm-ostwald/ |website=wilhelmexner.org |publisher=Österreichischer Gewerbeverein |access-date=18 June 2020}}</ref>

In 1904 he was elected a foreign member of the [[Royal Netherlands Academy of Arts and Sciences]].<ref>{{cite web|url=https://www.dwc.knaw.nl/biografie/pmknaw/?pagetype=authorDetail&aId=PE00002180 |title=Friedrich Wilhelm Ostwald (1853–1932) |publisher=Royal Netherlands Academy of Arts and Sciences |access-date=13 June 2020}}</ref> He became an honorary member of scientific societies in Germany, Sweden, Norway, the Netherlands, Russia, Great Britain, and the United States. Ostwald received honorary doctorates from various universities in Germany, Great Britain and the United States. In 1899 he was made a [[Geheimrat]] by the [[King of Saxony]], which by that time was a recognition of Ostwald's scholarly contributions.<ref name="Nobel" />

There is a Wilhelm Ostwald Park and Museum in [[Grimma|Grimma, Germany]], at the site of Ostwald's vacation home. This institution also houses many of Ostwald's scholarly works.<ref name="Ostwald Park">{{cite web |title=Physical Chemist, Nobel Laureate, and Polymath |url=https://wilhelm-ostwald-park.de/en/biografie |website=wilhelm-ostwald-park.de |publisher=Gerda and Klaus Tschira Foundation |access-date=8 August 2020}}</ref><ref>{{cite web |title=Wilhelm Ostwald Museum in Grossbothen |url=https://www.leipzig.travel/en/poi-detail-page/poi/infos/wilhelm-ostwald-museum-grossbothen/ |website=Leipzig Region. |access-date=30 October 2020}}</ref>

[[Ostwald (crater)|Ostwald crater]], which is on the [[Far side of the Moon|far side of the Earth's moon]], was named in honor of Wilhelm Ostwald.<ref name="Crater">{{cite web |title=Ostwald |url=https://planetarynames.wr.usgs.gov/Feature/4514 |website=Gazetteer of Planetary Nomenclature |publisher=International Astronomical Union |access-date=17 June 2020}}</ref>

==Personal life==
On 24 April 1880 Ostwald married Helene von Reyher (1854–1946), with whom he had five children. These were: Grete, (1882–1960) born in Riga and died in [[Großbothen]]; [[Wolfgang Ostwald|Wolfgang]] (1883–1943) born 1883 in Riga and died in [[Dresden]]; Elisabeth (1884– 1968) born in Riga and died in Großbothen; Walter (1886–1958) born in Riga and died in [[Freiburg im Breisgau]]; and Carl Otto (1890–1958) born in Leipzig and died in Leipzig. Wolfgang Ostwald became a notable scientist in the area of [[colloid]] chemistry.<ref>{{cite journal |last1=Oesper |first1=Ralph E. |title=Wolfgang Ostwald (1883–1943) |journal=Journal of Chemical Education |date=1 June 1945 |volume=22 |issue=6 |pages=263 |doi=10.1021/ed022p263 |bibcode=1945JChEd..22..263O |url=https://pubs.acs.org/doi/abs/10.1021/ed022p263# |access-date=29 August 2020 |issn=0021-9584}}</ref><ref>{{cite journal |last1=Hauser |first1=Ernst A. |title=The history of colloid science: In memory of Wolfgang Ostwald |journal=Journal of Chemical Education |date=January 1955 |volume=32 |issue=1 |pages=2 |doi=10.1021/ed032p2|bibcode=1955JChEd..32....2H }}</ref><ref>{{cite journal |last1=Findlay |first1=Alexander |title=An Introduction to Theoretical and Applied Colloid Chemistry: The World of Neglected Dimensions. By Dr. Wolfgang Ostwald, Privatdozent in the University of Leipsic. Authorised translation from the German by Dr. M. H. Fischer, Eichberg Professor of Physiology in the University of Cincinnati. (New York: John Wiley and Sons, Inc. London: Chapman and Hall, Ltd. 1917.) Price: 11s. 6d. net. |journal=Journal of the Society of Chemical Industry |date=31 December 1919 |volume=38 |issue=24 |pages=485–486 |doi=10.1002/jctb.5000382403|url=https://zenodo.org/record/2346535 }}</ref>

Ostwald was initiated to the [[Scottish Rite|Scottish Rite Masonry]] and became [[Grand Master (order)|Grand Master]] of the Grand Lodge "Zur Aufgehenden Sonne" in [[Bayreuth]].<ref>{{cite web | url = https://freimaurer-wiki.de/index.php/Wilhelm_Ostwald | title = Ostwald Wilhelm, in the "Masonic Encyclopedia" | website = freimaurer-wiki.de |language = de | archive-url = https://web.archive.org/web/20140406203120/https://freimaurer-wiki.de/index.php/Wilhelm_Ostwald | archive-date = 6 April 2014 | url-status = live}}</ref><ref>{{cite web | url = http://www.matawanlodge.org/famous.htm | title = Celebrating more than 100 years of the Freemasonry: famous Freemasons in the history | language = en | website = Mathawan Lodge No 192 F.A. & A.M., New Jersey | archive-url = https://web.archive.org/web/20080510153526/http://www.matawanlodge.org/famous.htm | archive-date = 10 May 2008 | url-status = usurped}}</ref>

In 1887, he moved to [[Leipzig]] where he worked for the rest of his life. At the time of his retirement, he moved to a country estate near Groβbothen, Saxony, which he named "Landhaus Energie". He lived at the country estate for most of the remainder of his life.<ref name="Deltete"/>

On his religious views, Ostwald was an atheist.<ref>{{cite book|title=Work in a Modern Society: The German Historical Experience in Comparative Perspective|year=2010|publisher=Berghahn Books|author=Jürgen Kocka|editor=Jürgen Kocka|page=45| isbn=978-1-84545-575-0 | url=https://books.google.com/books?id=cM5mf4jV7tEC |quote=Even Wilhelm Ostwald, who was the most radical atheist among these scholars, uses the instrument of the 'Monistic Sunday Sermons' to spread his ideas on rationality.}}</ref> Ostwald died in a hospital in Leipzig on 4 April 1932,<ref name="Nobel"/> and was buried at his country estate in [[Großbothen]], near Leipzig<ref>{{cite web |title=Wilhelm Ostwald Physical chemist, Nobel laureate and polymath |url=https://wilhelm-ostwald-park.de/en/biografie |website=Wilhelm Ostwald Park |access-date=30 October 2020}}</ref>

== In fiction ==
Ostwald appears as a character in [[Joseph Skibell]]'s 2010 novel, ''[[A Curable Romantic]]''.<ref name="Skibell">{{cite book |last1=Skibell |first1=Joseph |title=A Curable Romantic |date=7 November 2011 |publisher=Algonquin Books |location=Chapel Hill, North Carolina|isbn=9781616201210 |url=https://books.google.com/books?id=jw4rLmsNMt8C&pg=PA476}}</ref>

He is also mentioned in [[Italo Svevo]]'s 1923 novel, ''La coscienza di Zeno'', translated as ''[[Zeno's Conscience]]''.<ref>{{cite book |last1=Svevo |first1=Italo |title=Zeno's Conscience |date=2003 |publisher=Vintage Books |location=New York |isbn=9780375727764 |url=https://books.google.com/books?id=21NmvyHkxEsC&pg=PA31}}</ref>

==Representative publications==
[[File:Ostwald, Wilhelm – Grundriss der allgemeinen Chemie, 1899 – BEIC 6560168.jpg|thumb|''Grundriss der allgemeinen Chemie'', 1899]]
* {{Cite book|title=Grundriss der allgemeinen Chemie|volume=|publisher=Wilhelm Engelmann|location=Leipzig|year=1899|language=de|url=https://gutenberg.beic.it/webclient/DeliveryManager?pid=6560168}}
* {{Cite book | last=Ostwald | first=W. | year=1906 | title=Process of manufacturing nitric acid. Patent}}
* {{Cite book | last=Ostwald | first=W. | year=1909 | title=Energetische Grundlagen der Kulturwissenschaft | publisher=Leipzig, W. Klinkhardt | url=https://archive.org/details/energetischegru00ostwgoog | edition=1st | place=Leipzig}}
* {{Cite book | last=Couturat | first=L. |author2=Jespersen O. |author3=Lorenz R. |author4=Ostwald W. |author5=Pfaundler L. | year=1910 | title=International language and science: Considerations on the introduction of an international language into science | url=https://archive.org/details/internationallan029658mbp | publisher=Constable and Company Limited | place=London}}
* {{Cite book|title=Entwicklung der Elektrochemie|volume=|publisher=Alcan|location=Paris|year=1912|language=fr|url=https://gutenberg.beic.it/webclient/DeliveryManager?pid=6561905}}
* {{Cite book | last=Ostwald | first=W. | year=1917 | title=Grundriss der allgemeinen Chemie | publisher=Steinkopff | edition=5th | place=Dresden}}

== Books ==
* ''Lehrbuch der allgemeinen Chemie''.  Leipzig: W. Engelmann, 1896–1903. (2 vols.)<ref name="Bancroft"/>
* ''Leitlinien der Chemie: 7 gemeinverständliche Vorträge aus der Geschichte der Chemie''. Leipzig : Akad. Verl.-Ges., 1906. [http://nbn-resolving.de/urn:nbn:de:hbz:061:2-169620 Digital edition] of the [[University and State Library Düsseldorf]].
* ''The Scientific foundations of analytical chemistry'' London: Macmillan, 1908. {{OCLC|35430378}}
* ''Colour science'', London: Winsor & Newton, 1933. {{OCLC|499690961}}
* ''The color primer: A basic treatise on the color system of Wilhelm Ostwald'', New York, N.Y.: Van Nostrand Reinhold, 1969. {{OCLC|760593331}}
* ''Electrochemistry: History and theory : Elektrochemie: Ihre Geschichte und Lehre.'' New Delhi: Amerind Publishing Co. 1980. {{OCLC|702695546}} 
* ''Lebenslinien. Eine Selbstbiographie von Wilhelm Ostwald.'' Zweiter Teil, Leipzig 1887–1905 (3 vols). (Klasing & Co., g.m.b.H., Berlin 1927.)<ref name="Bhattacharyya"/> Translated as ''Wilhelm Ostwald: The Autobiography'' by Robert Jack. Springer, 2017.<ref>{{cite book |author-last=Ostwald|author-first=Wilhelm |translator-last1=Jack |translator-first1=Robert |title=Wilhelm Ostwald: The Autobiography |date=2017 |publisher=Springer}}</ref>

==See also==
* [[Colligative properties]]
* [[Electrode potential]]
* [[Energeticism]]
* [[List of Baltic Germans#Scientists|List of Baltic German scientists]]
* [[Timeline of hydrogen technologies]]
* [[Wilhelm Ostwald Institute]]

==References==
{{Reflist}}

==External links==
{{commons category}}
{{Wikisource author}}
* {{Gutenberg author | id=42408}}
* {{Internet Archive author |sname=Wilhelm Ostwald}}
* {{Librivox author}}
* {{PM20}}
* [https://www.wilhelm-ostwald-park.de/en/ Wilhelm Ostwald Park and Museum] 
* {{Nobelprize}} including the Nobel Lecture*, 12 December 1909 ''On Catalysis''

{{Nobel Prize in Chemistry Laureates 1901-1925}}
{{1909 Nobel Prize winners}}

{{Authority control}}

{{DEFAULTSORT:Ostwald, Wilhelm}}
[[Category:1853 births]]
[[Category:1932 deaths]]
[[Category:Scientists from Riga]]
[[Category:People from Riga county]]
[[Category:Baltic-German people from the Russian Empire]]
[[Category:Chemists from the Russian Empire]]
[[Category:Inventors from the Russian Empire]]
[[Category:Rare earth scientists]]
[[Category:Constructed language creators]]
[[Category:Idists]]
[[Category:Expatriates from the Russian Empire in the United States]]
[[Category:Emigrants from the Russian Empire to Germany]]
[[Category:University of Tartu alumni]]
[[Category:Academic staff of Leipzig University]]
[[Category:Riga State Gymnasium No.1 alumni]]
[[Category:Academic staff of Riga Technical University]]
[[Category:Members of the Prussian Academy of Sciences]]
[[Category:Members of the Royal Netherlands Academy of Arts and Sciences]]
[[Category:Members of the Royal Swedish Academy of Sciences]]
[[Category:Corresponding members of the Saint Petersburg Academy of Sciences]]
[[Category:Foreign associates of the National Academy of Sciences]]
[[Category:International members of the American Philosophical Society]]
[[Category:Nobel laureates in Chemistry]]
[[Category:Nobel laureates from the Russian Empire]]