View source for Timeline of chemistry

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[[File:A New System of Chemical Philosophy fp.jpg|thumb|An image from [[John Dalton]]'s ''A New System of Chemical Philosophy'', the first modern explanation of [[atomic theory]].]]
This timeline of [[chemistry]] lists important works, discoveries, ideas, inventions, and experiments that significantly changed humanity's understanding of the modern science known as chemistry, defined as the scientific study of the composition of matter and of its interactions.

Known as "[[the central science]]", the study of chemistry is strongly influenced by, and exerts a strong influence on, many other scientific and technological fields.  Many historical developments that are considered to have had a significant impact upon our modern understanding of chemistry are also considered to have been key discoveries in such fields as physics, biology, astronomy, geology, and materials science.<ref>{{cite web | title = Chemistry – The Central Science | work = The Chemistry Hall of Fame | publisher = York University | url = http://www.chem.yorku.ca/hall_of_fame/whychem.htm | access-date = 2006-09-12}}</ref>

==Pre-17th century==
[[File:Aristoteles Louvre.jpg|thumb|right|upright|Aristotle (384–322 BCE)]]
[[File:Zosimosapparat.jpg|thumb|right|upright|Ambix, cucurbit and retort, the alchemical implements of [[Zosimos of Panopolis|Zosimus]] c. 300, from [[Marcelin Berthelot]], ''Collection des anciens alchimistes grecs'' (3 vol., Paris, 1887–88)]]
[[File:Geber.jpg|thumb|right|upright|Imaginative depiction of [[Jabir ibn Hayyan|Jābir ibn Ḥayyān]] (Latin: [[Pseudo-Geber|Geber]])]]

Prior to the acceptance of the [[scientific method]] and its application to the field of chemistry, it is somewhat controversial to consider many of the people listed below as "chemists" in the modern sense of the word. However, the ideas of certain great thinkers, either for their prescience, or for their wide and long-term acceptance, bear listing here.

;c. 450 BC: [[Empedocles]] asserts that all things are composed of four primal roots (later to be renamed ''stoicheia'' or [[chemical element|elements]]): earth, air, fire, and water, whereby two active and opposing cosmic [[force]]s, love and strife, act upon these elements, combining and separating them into infinitely varied forms.<ref>Kingsley, K. Scarlett and Richard Parry, [https://plato.stanford.edu/archives/sum2020/entries/empedocles/ "Empedocles"], ''The Stanford Encyclopedia of Philosophy'' (Summer 2020 Edition), Edward N. Zalta (ed.).</ref>

;c. 440 BC: [[Leucippus]] and [[Democritus]] propose the idea of the atom, an indivisible particle that all matter is made of.  This idea is largely rejected by natural philosophers in favor of the Aristotelian view (see below).<ref>{{cite encyclopedia |last=Berryman |first=Sylvia |title=Leucippus |encyclopedia=Stanford Encyclopedia of Philosophy |publisher=Metaphysics Research Lab, CSLI, Stanford University |date=2004-08-14 |url=http://plato.stanford.edu/entries/leucippus/ |access-date=2007-03-11}}</ref><ref>{{cite encyclopedia |last=Berryman |first=Sylvia |title=Democritus |encyclopedia=Stanford Encyclopedia of Philosophy |publisher=Metaphysics Research Lab, CSLI, Stanford University |date=2004-08-15 |url=http://plato.stanford.edu/entries/democritus/ |access-date=2007-03-11}}</ref>

;c. 360 BC: [[Plato]] coins term ‘[[classical element|elements]]’ (''stoicheia'') and in his dialogue [[Timaeus (dialogue)|Timaeus]], which includes a discussion of the composition of inorganic and organic bodies and is a rudimentary treatise on chemistry, assumes that the minute particle of each element had a special geometric shape: [[tetrahedron]] (fire), [[octahedron]] (air), [[icosahedron]] (water), and [[cube]] (earth).<ref>{{cite web|last=Hillar |first=Marian |year=2004 |url=http://www.socinian.org/aristotles_de_anima.html |title=The Problem of the Soul in Aristotle's De anima |publisher=NASA WMAP |access-date=2006-08-10 |url-status=dead |archive-url=https://web.archive.org/web/20060909004214/http://www.socinian.org/aristotles_de_anima.html |archive-date=2006-09-09 }}</ref>

;c. 350 BC: [[Aristotle]], expanding on Empedocles, proposes idea of a substance as a combination of ''matter'' and ''form''.  Describes theory of the [[Classical element#Classical elements in Greece|Five Elements]], fire, water, earth, air, and aether.  This theory is largely accepted throughout the western world for over 1000 years.<ref>{{cite web | title = HISTORY/CHRONOLOGY OF THE ELEMENTS | url = http://hilltop.bradley.edu/~rbg/el.html | access-date = 2007-03-12}}</ref>

; c. 50 BC: [[Lucretius]] publishes ''[[On the Nature of Things|De Rerum Natura]]'', a poetic description of the ideas of [[atomism]].<ref>{{cite encyclopedia |last=Sedley |first=David |title=Lucretius |encyclopedia=Stanford Encyclopedia of Philosophy |publisher=Metaphysics Research Lab, CSLI, Stanford University |date=2004-08-04 |url=http://plato.stanford.edu/entries/lucretius/ |access-date=2007-03-11}}</ref>

;c. 300: [[Zosimos of Panopolis]] writes some of the oldest known books on [[alchemy]], which he defines as the study of the composition of waters, movement, growth, embodying and disembodying, drawing the spirits from bodies and bonding the spirits within bodies.<ref name=Mdream>{{cite book |last=Strathern |first=Paul |title=Mendeleyev's Dream – The Quest for the Elements |publisher=Berkley Books |year=2000 |isbn=978-0-425-18467-7}}</ref>

;c. 800: [[Sirr al-khaliqa|''The Secret of Creation'']] (Arabic: ''Sirr al-khalīqa''), an anonymous encyclopedic work on natural philosophy falsely attributed to [[Apollonius of Tyana]], records the earliest known version of the long-held theory that all metals are composed of various proportions of [[sulfur]] and [[Mercury (element)|mercury]].<ref>Kraus, Paul 1942-1943. ''Jâbir ibn Hayyân: Contribution à l'histoire des idées scientifiques dans l'Islam. I. Le corpus des écrits jâbiriens. II. Jâbir et la science grecque''. Cairo: Institut français d'archéologie orientale, vol. II, p. 1, note 1; Weisser, Ursula 1980. ''Das Buch über das Geheimnis der Schöpfung von Pseudo-Apollonios von Tyana''. Berlin: De Gruyter, p. 199. On the dating and historical background of the ''Sirr al-khalīqa'', see Kraus 1942−1943, vol. II, pp. 270–303; Weisser 1980, pp. 39–72. On the further history of this theory up to the eighteenth century, see Norris, John 2006. “The Mineral Exhalation Theory of Metallogenesis in Pre-Modern Mineral Science” in: ''Ambix'', 53, pp. 43–65.</ref> This same work also contains the earliest known version of the ''[[Emerald Tablet]]'',<ref>Weisser 1980, p. 46.</ref> a compact and cryptic [[Hermetica|Hermetic]] text which was still commented upon by [[Isaac Newton]].<ref>Isaac Newton. [http://purl.dlib.indiana.edu/iudl/newton/ALCH00017 "Keynes MS. 28"]. The Chymistry of Isaac Newton. Ed. William R. Newman. June 2010.</ref>

;c. 850–900: Arabic works attributed to [[Jabir ibn Hayyan|Jābir ibn Ḥayyān]] (Latin: Geber) introduce a systematic classification of chemical substances, and provide instructions for deriving an inorganic compound ([[sal ammoniac]] or [[ammonium chloride]]) from organic substances (such as plants, blood, and hair) by chemical means.<ref>{{cite journal <!-- Citation bot bypass-->|last1=Stapleton|first1=Henry E.|author1-link=Henry Ernest Stapleton|last2=Azo|first2=R.F.|last3=Hidayat Husain|first3=M.|year=1927|title=Chemistry in Iraq and Persia in the Tenth Century A.D.|journal=Memoirs of the Asiatic Society of Bengal|volume=VIII|issue=6|pages=317–418|oclc=706947607|url=http://www.southasiaarchive.com/Content/sarf.100203/231270}} pp. 338–340; {{Cite book|last=Kraus|first=Paul|author-link=Paul Kraus (Arabist)|year=1942–1943|title=Jâbir ibn Hayyân: Contribution à l'histoire des idées scientifiques dans l'Islam. I. Le corpus des écrits jâbiriens. II. Jâbir et la science grecque|publisher=Institut Français d'Archéologie Orientale|location=Cairo|oclc=468740510|isbn=978-3-487-09115-0}} vol. II, pp. 41–42.</ref>

;c. 900: [[Abu Bakr al-Razi|Abū Bakr al-Rāzī]] (Latin: Rhazes), a [[Alchemy and chemistry in Islam|Persian alchemist]], conducts experiments with the distillation of sal ammoniac (ammonium chloride), [[vitriols]] (hydrated [[sulfates]] of various metals), and other [[Salt (chemistry)|salts]],<ref>{{cite book|last=Multhauf|first=Robert P.|author-link=Robert P. Multhauf|year=1966|title=The Origins of Chemistry|location=London|publisher=Oldbourne|isbn=}} pp. 141-142.</ref> representing the first step in a long process that would eventually lead to the thirteenth-century discovery of the [[mineral acids]].<ref>{{harvnb|Multhauf|1966|pp=162–163}}.</ref>

;c. 1000: [[Abū al-Rayhān al-Bīrūnī]]<ref>{{cite journal |last1=Marmura |first1=Michael E. |year=1965 |title=''An Introduction to Islamic Cosmological Doctrines. Conceptions of Nature and Methods Used for Its Study by the Ikhwan Al-Safa'an, Al-Biruni, and Ibn Sina'' by Seyyed Hossein Nasr |journal=Speculum |volume=40 |issue=4 |pages=744–746 |doi=10.2307/2851429|title-link=Hossein Nasr |jstor=2851429 }}</ref> and [[Avicenna]],<ref>[[Robert Briffault]] (1938). ''The Making of Humanity'', p. 196-197.</ref> both Persian philosophers, deny the possibility of the [[Philosopher's stone|transmutation of metals]].

;c. 1100–1200: Recipes for the production of ''aqua ardens'' ("burning water", i.e., [[ethanol]]) by distilling wine with [[common salt]] start to appear in a number of Latin alchemical works.<ref>{{harvnb|Multhauf|1966|pp=204–206}}.</ref>

;c. 1220: [[Robert Grosseteste]] publishes several Aristotelian commentaries where he lays out an early framework for the [[scientific method]].<ref>{{Cite CE1913|wstitle=Robert Grosseteste}}</ref>

;c 1250: The works of [[Taddeo Alderotti]] (1223–1296) describe a method for concentrating [[ethanol]] involving repeated [[fractional distillation]] through a water-cooled still, by which an ethanol purity of 90% could be obtained.<ref>{{cite book|last1=Holmyard|first1=Eric John|author1-link=Eric John Holmyard|date=1957|title=Alchemy|location=Harmondsworth|publisher=Penguin Books|isbn=978-0-486-26298-7}} pp. 51–52.</ref>

;c 1260: St [[Albertus Magnus]] discovers [[arsenic]]<ref name="BuildingBlocks451-3">{{cite book |last=Emsley |first=John |title=Nature's Building Blocks: An A-Z Guide to the Elements |year=2001 |isbn=978-0-19-850341-5 |pages=43, 513, 529 |publisher=[[Oxford University Press]] |location=Oxford}}</ref>{{Better source needed|date=January 2021}} and [[silver nitrate]].<ref>{{cite web |last=Davidson |first=Michael W. |others =National High Magnetic Field Laboratory at The Florida State University |title=Molecular Expressions: Science, Optics and You&nbsp;— Timeline&nbsp;— Albertus Magnus |publisher=The Florida State University |date=2003-08-01 |url=http://micro.magnet.fsu.edu/optics/timeline/people/magnus.html |access-date=2009-11-28}}</ref>{{Better source needed|date=January 2021}} He also made one of the first references to [[sulfuric acid]].<ref name="Karpenko">Vladimir Karpenko, John A. Norris(2001), [http://www.chemicke-listy.cz/docs/full/2002_12_05.pdf Vitriol in the history of Chemistry], [[Charles University in Prague|Charles University]]</ref>

;c. 1267: [[Roger Bacon]] publishes ''Opus Maius'', which among other things, proposes an early form of the scientific method, and contains results of his experiments with [[gunpowder]].<ref>{{cite web |last1=O'Connor |first1=J. J. |last2=Robertson |first2=E. F. |title=Roger Bacon |work=MacTutor |publisher=School of Mathematics and Statistics University of St Andrews, Scotland |year=2003 |url=http://www-groups.dcs.st-and.ac.uk/~history/Biographies/Bacon.html |access-date=2007-03-12 |archive-date=2008-03-07 |archive-url=https://web.archive.org/web/20080307150151/http://www-groups.dcs.st-and.ac.uk/~history/Biographies/Bacon.html |url-status=dead }}</ref>

;c. 1310: [[Pseudo-Geber]], an anonymous alchemist who wrote under the name of Geber (i.e., Jābir ibn Hayyān, see above), publishes the {{lang|la|Summa perfectionis magisterii}}. This work contains experimental demonstrations of the [[corpuscularianism|corpuscular]] nature of matter that would still be used by seventeenth-century chemists such as [[Daniel Sennert]].<ref>Newman, William R. 1985. “New Light on the Identity of Geber” in: ''Sudhoffs Archiv'', 69(1), pp. 76-90; Newman, William R. 2001. "Experimental Corpuscular Theory in Aristotelian Alchemy: From Geber to Sennert" in: Christoph Lüthy (ed.). ''Late Medieval and Early Modern Corpuscular Matter Theories''. Leiden: Brill, 2001, pp. 291-329; Newman, William R. 2006. ''Atoms and Alchemy: Chymistry and the Experimental Origins of the Scientific Revolution''. Chicago: University of Chicago Press.</ref> Pseudo-Geber is one of the first alchemists to describe [[mineral acids]] such as {{lang|la|[[aqua fortis]]}} or 'strong water' (nitric acid, capable of dissolving silver) and {{lang|la|[[aqua regia]]}} or 'royal water' (a mixture of nitric acid and [[hydrochloric acid]], capable of dissolving gold and [[platinum]]).<ref>{{cite EB1911|last=Ross |first=Hugh Munro |wstitle=Alchemy#Literature of Alchemy|display=Alchemy § Literature of Alchemy |volume=1 |page=520}}</ref>

;c. 1530: [[Paracelsus]] develops the study of [[iatrochemistry]], a subdiscipline of alchemy dedicated to extending life, thus being the roots of the modern [[pharmaceutical industry]].  It is also claimed that he is the first to use the word "chemistry".<ref name=Mdream/>

;1597: [[Andreas Libavius]] publishes ''Alchemia'', a prototype [[chemistry]] textbook.<ref>{{cite web | title = From liquid to vapor and back: origins | work = Special Collections Department | publisher = University of Delaware Library | url = http://www.lib.udel.edu/ud/spec/exhibits/vapor/origins.htm | access-date = 2007-03-12}}</ref>

==17th and 18th centuries==
;1605:[[Sir Francis Bacon]] publishes ''The Proficience and Advancement of Learning'', which contains a description of what would later be known as the [[scientific method]].<ref>{{cite web|last=Asarnow |first=Herman |title=Sir Francis Bacon: Empiricism |work=An Image-Oriented Introduction to Backgrounds for English Renaissance Literature |publisher=University of Portland |date=2005-08-08 |url=http://faculty.up.edu/asarnow/eliz4.htm |access-date=2007-02-22 |url-status=dead |archive-url=https://web.archive.org/web/20070201210445/http://faculty.up.edu/asarnow/eliz4.htm |archive-date=2007-02-01 }}</ref>

;1605:[[Michal Sedziwój]] publishes the alchemical treatise ''A New Light of Alchemy'' which proposed the existence of the "food of life" within air, much later recognized as [[oxygen]].<ref>{{cite web | title = Sedziwój, Michal | work = infopoland: Poland on the Web | publisher = University at Buffalo | url = http://info-poland.buffalo.edu/web/sci_health/science/scientists/sedziwoj/link.shtml | access-date = 2007-02-22 | url-status = dead | archive-url = https://web.archive.org/web/20060902171948/http://info-poland.buffalo.edu/web/sci_health/science/scientists/sedziwoj/link.shtml | archive-date = 2006-09-02 }}</ref>

;1615:[[Jean Beguin]] publishes the ''[[Tyrocinium Chymicum]]'', an early chemistry textbook, and in it draws the first-ever [[chemical equation]].<ref>{{cite journal |last=Crosland |first=M.P. |year=1959 |title=The use of diagrams as chemical 'equations' in the lectures of William Cullen and Joseph Black |journal=Annals of Science |volume=15 |issue=2 |pages=75–90 |doi=10.1080/00033795900200088}}</ref>

;1637:[[René Descartes]] publishes ''[[Discourse on the Method|Discours de la méthode]]'', which contains an outline of the scientific method.<ref>{{Cite CE1913|wstitle= René Descartes}}</ref>

;1648:Posthumous publication of the book ''Ortus medicinae'' by [[Jan Baptist van Helmont]], which is cited by some as a major transitional work between alchemy and chemistry, and as an important influence on [[Robert Boyle]].  The book contains the results of numerous experiments and establishes an early version of the [[law of conservation of mass]].<ref>{{cite web | title = Johann Baptista van Helmont | work = History of Gas Chemistry | publisher = Center for Microscale Gas Chemistry, Creighton University | date = 2005-09-25 | url = http://mattson.creighton.edu/History_Gas_Chemistry/vanHelmont.html | access-date = 2007-02-23}}</ref>

[[File:The Sceptical Chymist.jpg|thumb|right|upright|Title page of ''The Sceptical Chymist'' by Robert Boyle (1627–91)]]
;1661:[[Robert Boyle]] publishes ''[[The Sceptical Chymist]]'', a treatise on the distinction between chemistry and [[alchemy]].  It contains some of the earliest modern ideas of [[atom]]s, [[molecule]]s, and [[chemical reaction]], and marks the beginning of the history of modern chemistry.<ref name=Boyle>{{cite book | chapter = Robert Boyle | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation | year = 2005 }}</ref>

;1662:Robert Boyle proposes [[Boyle's law]], an experimentally based description of the behavior of [[gas]]es, specifically the relationship between [[pressure]] and [[volume]].<ref name=Boyle/>

;1735:Swedish chemist [[Georg Brandt]] analyzes a dark blue pigment found in copper ore. Brandt demonstrated that the pigment contained a new element, later named [[cobalt]].<ref>Georg Brandt first showed cobalt to be a new metal in: G. Brandt (1735) "Dissertatio de semimetallis" (Dissertation on semi-metals), ''Acta Literaria et Scientiarum Sveciae'' (Journal of Swedish literature and sciences), vol. 4, pages 1–10.<br />See also: '''(1)''' G. Brandt (1746) "Rön och anmärkningar angäende en synnerlig färg — cobolt" (Observations and remarks concerning an extraordinary pigment — cobalt), ''Kongliga Svenska vetenskapsakademiens handlingar'' (Transactions of the Royal Swedish Academy of Science), vol.7, pages 119–130; '''(2)''' G. Brandt (1748) "Cobalti nova species examinata et descripta" (Cobalt, a new element examined and described), ''Acta Regiae Societatis Scientiarum Upsaliensis'' (Journal of the Royal Scientific Society of Uppsala), 1st series, vol. 3, pages 33–41; '''(3)''' James L. Marshall and Virginia R. Marshall (Spring 2003) [http://www.chem.unt.edu/Rediscovery/Riddarhyttan.pdf "Rediscovery of the Elements: Riddarhyttan, Sweden,"] {{webarchive|url=https://web.archive.org/web/20100703175508/http://www.chem.unt.edu/Rediscovery/Riddarhyttan.pdf |date=2010-07-03 }} ''The Hexagon'' (official journal of the [[Alpha Chi Sigma]] fraternity of chemists), vol. 94, no. 1, pages 3–8.</ref><ref name="Wang">{{cite journal |journal=Journal of the Minerals, Metals and Materials Society |volume=58 |issue=10 |year=2006 |doi=10.1007/s11837-006-0201-y |pages=47–50 |title=Cobalt—Its recovery, recycling, and application |first=Shijie |last=Wang |bibcode=2006JOM....58j..47W |s2cid=137613322 }}</ref>

;1754:[[Joseph Black]] isolates [[carbon dioxide]], which he called "fixed air".<ref>{{cite web |last=Cooper |first=Alan |title=Joseph Black |work=History of Glasgow University Chemistry Department |publisher=University of Glasgow Department of Chemistry |year=1999 |url=http://www.chem.gla.ac.uk/dept/black.htm |access-date=2006-02-23 |archive-url=https://web.archive.org/web/20060410074412/http://www.chem.gla.ac.uk/dept/black.htm <!-- Bot retrieved archive --> |archive-date=2006-04-10}}</ref>

[[File:Chemielabor des 18. Jahrhunderts, Naturhistorisches Museum Wien.jpg|thumb|A typical chemical laboratory of the 18th century]]

;1757:[[Louis Claude Cadet de Gassicourt]], while investigating arsenic compounds, creates [[Cadet's fuming liquid]], later discovered to be [[cacodyl oxide]], considered to be the first synthetic [[organometallic]] compound.<ref>{{cite journal |title=Cadet's Fuming Arsenical Liquid and the Cacodyl Compounds of Bunsen |first=Dietmar |last=Seyferth |journal=Organometallics |year=2001 |volume=20 |issue=8 |pages=1488–1498 |doi=10.1021/om0101947 |doi-access=free }}</ref>

;1758:[[Joseph Black]] formulates the concept of [[latent heat]] to explain the [[thermochemistry]] of [[phase changes]].<ref>{{cite book |last=Partington |first=J.R. |title=A Short History of Chemistry |url=https://archive.org/details/shorthistoryofch0000part_q6h4 |url-access=registration |publisher=Dover Publications, Inc |year=1989 |isbn=978-0-486-65977-0 |author-link=J. R. Partington}}</ref>

;1766:[[Henry Cavendish]] discovers [[hydrogen]] as a colorless, odourless gas that burns and can form an explosive mixture with air.<ref name=pt>{{cite journal |last=Cavendish |first=Henry |title=Three Papers Containing Experiments on Factitious Air, by the Hon. Henry Cavendish |journal=Philosophical Transactions |year=1766 |volume=56 |pages=141–184 |url=https://books.google.com/books?id=ygqYnSR3oe0C&q=the+scientific+papers+cavendish |access-date=6 November 2007 |doi=10.1098/rstl.1766.0019 |publisher=The University Press|doi-access=free |bibcode=1766RSPT...56..141C }}</ref>

;1773–1774: [[Carl Wilhelm Scheele]] and [[Joseph Priestley]] independently isolate oxygen, called by Priestley "dephlogisticated air" and Scheele "fire air".<ref>{{cite book | chapter = Joseph Priestley | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation | year = 2005 }}</ref><ref>{{cite web | title = Carl Wilhelm Scheele | work = History of Gas Chemistry | publisher = Center for Microscale Gas Chemistry, Creighton University | date = 2005-09-11 | url = http://mattson.creighton.edu/History_Gas_Chemistry/Scheele.html | access-date = 2007-02-23}}</ref>

[[File:David - Portrait of Monsieur Lavoisier (cropped).jpg|thumb|right|upright|Antoine-Laurent de Lavoisier (1743–94) is considered the "[[List of people considered father or mother of a scientific field#Chemistry|Father of Modern Chemistry]]".]]

;1778:[[Antoine Lavoisier]], considered "The father of modern chemistry",<ref>"Lavoisier, Antoine." Encyclopædia Britannica. 2007. Encyclopædia Britannica Online. 24 July 2007  <http://www.britannica.com/eb/article-9369846>.</ref> recognizes and names oxygen, and recognizes its importance and role in combustion.<ref name=lavoisier>{{cite web |last=Weisstein |first=Eric W. |title=Lavoisier, Antoine (1743–1794) |work=Eric Weisstein's World of Scientific Biography |publisher=Wolfram Research Products |year=1996 |url=http://scienceworld.wolfram.com/biography/Lavoisier.html |access-date=2007-02-23}}</ref>

;1787:Antoine Lavoisier publishes ''Méthode de nomenclature chimique'', the first modern system of chemical nomenclature.<ref name=lavoisier/>

;1787:[[Jacques Charles]] proposes [[Charles's law]], a corollary of Boyle's law, describes relationship between [[temperature]] and volume of a gas.<ref>{{cite web|title=Jacques Alexandre César Charles |work=Centennial of Flight |publisher=U.S. Centennial of Flight Commission |year=2001 |url=http://www.centennialofflight.gov/essay/Dictionary/Charles/DI16.htm |access-date=2007-02-23 |url-status=dead |archive-url=https://web.archive.org/web/20070224222637/http://www.centennialofflight.gov/essay/Dictionary/Charles/DI16.htm |archive-date=2007-02-24 }}</ref>

;1789:Antoine Lavoisier publishes ''[[Traité Élémentaire de Chimie]]'', the first modern chemistry textbook.  It is a complete survey of (at that time) modern chemistry, including the first concise definition of the [[law of conservation of mass]], and thus also represents the founding of the discipline of [[stoichiometry]] or quantitative chemical analysis.<ref name=lavoisier/><ref>{{cite book |last=Burns |first=Ralph A. |title=Fundamentals of Chemistry |url=https://archive.org/details/fundamentalsofch0003burn |url-access=registration |publisher=Prentice Hall |year=1999 |page=[https://archive.org/details/fundamentalsofch0003burn/page/32 32] |isbn=978-0-02-317351-6}}</ref>

;1797:[[Joseph Proust]] proposes the [[law of definite proportions]], which states that elements always combine in small, whole number ratios to form compounds.<ref>{{cite web | title = Proust, Joseph Louis (1754–1826) | work = 100 Distinguished Chemists | publisher = European Association for Chemical and Molecular Science | year = 2005 | url = http://www.euchems.org/Distinguished/19thCentury/proustlouis.asp | access-date = 2007-02-23 | archive-url = https://web.archive.org/web/20080515224050/http://www.euchems.org/Distinguished/19thCentury/proustlouis.asp | archive-date = 2008-05-15}}</ref>

;1800:[[Alessandro Volta]] devises the first [[Voltaic pile|chemical battery]], thereby founding the discipline of [[electrochemistry]].<ref>{{cite web | title = Inventor Alessandro Volta Biography | work = The Great Idea Finder | year = 2005 | url = http://www.ideafinder.com/history/inventors/volta.htm | access-date = 2007-02-23}}</ref>

==19th century==
[[File:Dalton John desk.jpg|thumb|right|180px|John Dalton (1766–1844)]]
;1803:[[John Dalton]] proposes [[Dalton's law]], which describes relationship between the components in a mixture of gases and the relative pressure each contributes to that of the overall mixture.<ref name=dalton>{{cite book | chapter = John Dalton | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation | year = 2005 }}</ref>

;1805:[[Joseph Louis Gay-Lussac]] discovers that water is composed of two parts hydrogen and one part oxygen by volume.<ref>{{cite book | chapter = Joseph Louis Gay-Lussac | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation | year = 2005 }}</ref>

;1808:Joseph Louis Gay-Lussac collects and discovers several chemical and physical properties of air and of other gases, including experimental proofs of [[Boyle's law|Boyle's]] and [[Charles's law]]s, and of relationships between density and composition of gases.<ref name=JLGL>{{cite web | title = December 6 Births | work = Today in Science History | year = 2007 | url = http://www.todayinsci.com/12/12_06.htm | access-date = 2007-03-12}}</ref>

;1808:John Dalton publishes ''New System of Chemical Philosophy'', which contains first modern scientific description of the [[atomic theory]], and clear description of the [[law of multiple proportions]].<ref name=dalton/>

;1808:[[Jöns Jakob Berzelius]] publishes ''Lärbok i Kemien'' in which he proposes modern [[chemical symbols]] and notation, and of the concept of relative [[atomic weight]].<ref>{{cite book | chapter = Jöns Jakob Berzelius | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation | year = 2005 }}</ref>

;1811:[[Amedeo Avogadro]] proposes [[Avogadro's law]], that equal volumes of gases under constant temperature and pressure contain equal number of molecules.<ref>{{cite web | title = Michael Faraday | work = Famous Physicists and Astronomers | url = http://www.phy.hr/~dpaar/fizicari/xfaraday.html | access-date = 2007-03-12}}</ref>
[[File:Urea Structural Formula V2.svg|thumb|right|160px|Structural formula of urea]]
;1825:[[Friedrich Wöhler]] and [[Justus von Liebig]] perform the first confirmed discovery and explanation of [[isomers]], earlier named by Berzelius.  Working with cyanic acid and fulminic acid, they correctly deduce that isomerism was caused by differing arrangements of atoms within a molecular structure.<ref name=wohlerliebig>{{cite book | chapter = Justus von Liebig and Friedrich Wöhler  | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation | year = 2005 }}</ref>

;1827:[[William Prout]] classifies biomolecules into their modern groupings: [[carbohydrates]], [[proteins]] and [[lipids]].<ref name=Prout>{{cite web | title = William Prout | url = http://www.cartage.org.lb/en/themes/Biographies/MainBiographies/P/Prout/1.html | access-date = 2007-03-12 | url-status = dead | archive-url = https://web.archive.org/web/20070926215538/http://www.cartage.org.lb/en/themes/Biographies/MainBiographies/P/Prout/1.html | archive-date = 2007-09-26 }}</ref>

;1828:Friedrich Wöhler synthesizes [[urea]], thereby establishing that organic compounds could be produced from inorganic starting materials, disproving the theory of [[vitalism]].<ref name=wohlerliebig/>

;1832:Friedrich Wöhler and Justus von Liebig discover and explain [[functional group]]s and [[radical (chemistry)|radicals]] in relation to organic chemistry.<ref name=wohlerliebig/>

;1840:[[Germain Hess]] proposes [[Hess's law]], an early statement of the [[law of conservation of energy]], which establishes that energy changes in a chemical process depend only on the states of the starting and product materials and not on the specific pathway taken between the two states.<ref>{{cite web|title=Hess, Germain Henri |url=http://www.cartage.org.lb/en/themes/Biographies/MainBiographies/H/Hess/1.html |access-date=2007-03-12 |url-status=dead |archive-url=https://web.archive.org/web/20070209062053/http://www.cartage.org.lb/en/themes/Biographies/MainBiographies/H/Hess/1.html |archive-date=2007-02-09 }}</ref>

;1847:[[Hermann Kolbe]] obtains [[acetic acid]] from completely inorganic sources, further disproving vitalism.<ref>{{cite web | title = Kolbe, Adolph Wilhelm Hermann | publisher = European Association for Chemical and Molecular Sciences | work = 100 Distinguished European Chemists | year = 2005 | url = http://www.euchems.org/Distinguished/19thCentury/kolbeadolph.asp | access-date = 2007-03-12 | archive-url = https://web.archive.org/web/20081011092124/http://www.euchems.org/Distinguished/19thCentury/kolbeadolph.asp | archive-date = 2008-10-11}}</ref>

;1848:[[Lord Kelvin]] establishes concept of [[absolute zero]], the temperature at which all molecular motion ceases.<ref>{{cite web |last=Weisstein |first=Eric W. |title=Kelvin, Lord William Thomson (1824–1907) |work=Eric Weisstein's World of Scientific Biography |publisher=Wolfram Research Products |year=1996 |url=http://scienceworld.wolfram.com/biography/Kelvin.html |access-date=2007-03-12}}</ref>

;1849:[[Louis Pasteur]] discovers that the [[racemic]] form of [[tartaric acid]] is a mixture of the levorotatory and dextrotatory forms, thus clarifying the nature of [[optical rotation]] and advancing the field of [[stereochemistry]].<ref>{{cite web | title = History of Chirality | publisher = Stheno Corporation | year = 2006 | url = http://www.sthenocorp.com/history.htm | access-date = 2007-03-12 |archive-url = https://web.archive.org/web/20070307222010/http://www.sthenocorp.com/history.htm <!-- Bot retrieved archive --> |archive-date = 2007-03-07}}</ref>

;1852:[[August Beer]] proposes [[Beer's law]], which explains the relationship between the composition of a mixture and the amount of light it will absorb.  Based partly on earlier work by [[Pierre Bouguer]] and [[Johann Heinrich Lambert]], it establishes the [[analytical chemistry|analytical]] technique known as [[spectrophotometry]].<ref>{{cite web | title = Lambert-Beer Law | publisher = Sigrist-Photometer AG | date = 2007-03-07 | url = http://www.photometer.com/en/abc/abc_061.htm | access-date = 2007-03-12}}</ref>

;1855:[[Benjamin Silliman, Jr.]] pioneers methods of [[petroleum cracking]], which makes the entire modern [[petrochemical industry]] possible.<ref>{{cite web|title=Benjamin Silliman, Jr. (1816–1885) |work=Picture History |publisher=Picture History LLC |year=2003 |url=http://www.picturehistory.com/find/p/17879/mcms.html |access-date=2007-03-24 |url-status=dead |archive-url=https://web.archive.org/web/20070707023346/http://www.picturehistory.com/find/p/17879/mcms.html |archive-date=2007-07-07 }}</ref>

;1856:[[Sir William Henry Perkin|William Henry Perkin]] synthesizes [[Perkin's mauve]], the first synthetic dye.  Created as an accidental byproduct of an attempt to create [[quinine]] from [[coal tar]].  This discovery is the foundation of the dye synthesis industry, one of the earliest successful chemical industries.<ref>{{cite book | chapter = William Henry Perkin  | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation | year = 2005 }}</ref>

;1857:[[Friedrich August Kekulé von Stradonitz]] proposes that [[carbon]] is tetravalent, or forms exactly four [[chemical bonds]].<ref name=kekule>{{cite book | chapter = Archibald Scott Couper and August Kekulé von Stradonitz | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation | year = 2005 }}</ref>

;1859–1860: [[Gustav Kirchhoff]] and [[Robert Bunsen]] lay the foundations of [[spectroscopy]] as a means of chemical analysis, which lead them to the discovery of [[caesium]] and [[rubidium]]. Other workers soon used the same technique to discover [[indium]], [[thallium]], and [[helium]].<ref>{{cite web |last1=O'Connor |first1=J. J. |last2=Robertson |first2=E.F. |title=Gustav Robert Kirchhoff |work=MacTutor |publisher=School of Mathematics and Statistics University of St Andrews, Scotland |year=2002 |url=http://www-groups.dcs.st-and.ac.uk/~history/Biographies/Kirchhoff.html |access-date=2007-03-24 |archive-date=2009-10-15 |archive-url=https://web.archive.org/web/20091015115130/http://www-groups.dcs.st-and.ac.uk/~history/Biographies/Kirchhoff.html |url-status=dead }}</ref>

;1860:[[Stanislao Cannizzaro]], resurrecting Avogadro's ideas regarding diatomic molecules, compiles a table of [[atomic weight]]s and presents it at the 1860 [[Karlsruhe Congress]], ending decades of conflicting atomic weights and molecular formulas, and leading to Mendeleev's discovery of the periodic law.<ref>Eric R. Scerri, ''The Periodic Table: Its Story and Its Significance'', Oxford University Press, 2006.</ref>

;1862:[[Alexander Parkes]] exhibits [[Parkesine]], one of the earliest [[synthetic polymer]]s, at the International Exhibition in London.  This discovery formed the foundation of the modern [[plastics industry]].<ref>{{cite web | title = Alexander Parkes (1813–1890) | work = People & Polymers | publisher = Plastics Historical Society | url = http://www.plastiquarian.com/parkes.htm | access-date = 2007-03-24 |archive-url = https://web.archive.org/web/20070315102347/http://www.plastiquarian.com/parkes.htm <!-- Bot retrieved archive --> |archive-date = 2007-03-15}}</ref>

;1862:[[Alexandre-Emile Béguyer de Chancourtois]] publishes the telluric helix, an early, three-dimensional version of the [[Periodic table|periodic table of the elements]].<ref name=periodic>{{cite web | title = The Periodic Table | publisher = The Third Millennium Online | url = http://www.3rd1000.com/history/periodic.htm | access-date = 2007-03-24}}</ref>

;1864:[[John Alexander Reina Newlands|John Newlands]] proposes the law of octaves, a precursor to the [[periodic law]].<ref name=periodic/>

;1864:[[Lothar Meyer]] develops an early version of the periodic table, with 28 elements organized by [[Valence (chemistry)|valence]].<ref name=meyermendeleev>{{cite book | chapter = Julius Lothar Meyer and Dmitri Ivanovich Mendeleev  | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation | year = 2005 }}</ref>

;1864:[[Cato Maximilian Guldberg]] and [[Peter Waage]], building on [[Berthollet|Claude Louis Berthollet]]'s ideas, proposed the [[law of mass action]].<ref name="GW1">C.M. Guldberg and P. Waage,"Studies Concerning Affinity" ''C. M. Forhandlinger: Videnskabs-Selskabet i Christiana'' (1864),  35</ref><ref name="GW2">P. Waage, "Experiments for Determining the Affinity Law" ,''Forhandlinger i Videnskabs-Selskabet i Christiania'', (1864) 92.</ref><ref name="GW3">C.M. Guldberg, "Concerning the Laws of Chemical Affinity", ''C. M. Forhandlinger i Videnskabs-Selskabet i Christiania'' (1864) 111</ref>

;1865:[[Johann Josef Loschmidt]] determines exact number of molecules in a [[mole (unit)|mole]], later named [[Avogadro constant]].<ref>{{Cite web|url=http://www.uh.edu/engines/epi1858.htm|title=No. 1858: Johann Josef Loschmidt|website=www.uh.edu|access-date=2016-10-09}}</ref>

;1865:Friedrich August Kekulé von Stradonitz, based partially on the work of Loschmidt and others, establishes structure of benzene as a six carbon ring with alternating [[Single bond|single]] and [[double bond]]s.<ref name=kekule/>

;1865:[[Adolf von Baeyer]] begins work on [[indigo dye]], a milestone in modern industrial organic chemistry which revolutionizes the dye industry.<ref>{{cite web | title = Adolf von Baeyer: The Nobel Prize in Chemistry 1905 | work = Nobel Lectures, Chemistry 1901–1921 | publisher = Elsevier Publishing Company | year = 1966 | url = http://nobelprize.org/nobel_prizes/chemistry/laureates/1905/baeyer-bio.html | access-date = 2007-02-28}}</ref>
[[File:Mendeleev's 1869 periodic table.png|thumb|right|Mendeleev's 1869 [[Periodic table]]]]
;1869:[[Dmitri Mendeleev]] publishes the first modern periodic table, with the 66 known elements organized by atomic weights.  The strength of his table was its ability to accurately predict the properties of as-yet unknown elements.<ref name=periodic/><ref name=meyermendeleev/>

;1873:[[Jacobus Henricus van 't Hoff]] and [[Joseph Achille Le Bel]], working independently, develop a model of [[chemical bonds|chemical bonding]] that explains the chirality experiments of Pasteur and provides a physical cause for [[optical activity]] in chiral compounds.<ref>{{cite book | chapter = Jacobus Henricus van't Hoff | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation | year = 2005 }}</ref>

;1876:[[Josiah Willard Gibbs]] publishes ''[[On the Equilibrium of Heterogeneous Substances]]'', a compilation of his work on thermodynamics and [[physical chemistry]] which lays out the concept of [[Thermodynamic free energy|free energy]] to explain the physical basis of chemical equilibria.<ref>{{cite web |last1=O'Connor |first1=J. J. |last2=Robertson |first2=E.F. |title=Josiah Willard Gibbs |work=MacTutor |publisher=School of Mathematics and Statistics University of St Andrews, Scotland |year=1997 |url=http://www-groups.dcs.st-and.ac.uk/~history/Biographies/Gibbs.html |access-date=2007-03-24 |archive-date=2010-03-27 |archive-url=https://web.archive.org/web/20100327095905/http://www-groups.dcs.st-and.ac.uk/~history/Biographies/Gibbs.html |url-status=dead }}</ref>

;1877:[[Ludwig Boltzmann]] establishes statistical derivations of many important physical and chemical concepts, including [[entropy]], and distributions of molecular velocities in the gas phase.<ref>{{cite web |last=Weisstein |first=Eric W. |title=Boltzmann, Ludwig (1844–1906) |work=Eric Weisstein's World of Scientific Biography |publisher=Wolfram Research Products |year=1996 |url=http://scienceworld.wolfram.com/biography/Boltzmann.html |access-date=2007-03-24}}</ref>

;1883:[[Svante Arrhenius]] develops [[ion]] theory to explain conductivity in [[electrolyte]]s.<ref>{{cite book | chapter = Svante August Arrhenius | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation | year = 2005 }}</ref>

;1884:Jacobus Henricus van 't Hoff publishes ''Études de Dynamique chimique'', a seminal study on [[chemical kinetics]].<ref>{{cite web | title = Jacobus H. van 't Hoff: The Nobel Prize in Chemistry 1901 | work = Nobel Lectures, Chemistry 1901–1921 | publisher = Elsevier Publishing Company | year = 1966 | url = http://nobelprize.org/nobel_prizes/chemistry/laureates/1901/hoff-bio.html | access-date = 2007-02-28}}</ref>

;1884:[[Hermann Emil Fischer]] proposes structure of [[purine]], a key structure in many biomolecules, which he later synthesized in 1898.  Also begins work on the chemistry of [[glucose]] and related [[sugar]]s.<ref>{{cite web | title = Emil Fischer: The Nobel Prize in Chemistry 1902 | work = Nobel Lectures, Chemistry 1901–1921 | publisher = Elsevier Publishing Company | year = 1966 | url = http://nobelprize.org/nobel_prizes/chemistry/laureates/1902/fischer-bio.html | access-date = 2007-02-28}}</ref>

;1884:[[Henry Louis Le Chatelier]] develops [[Le Chatelier's principle]], which explains the response of dynamic [[chemical equilibrium|chemical equilibria]] to external stresses.<ref>{{cite book | chapter = Henry Louis Le Châtelier | title = World of Scientific Discovery | publisher = Thomson Gale | year = 2005 | url = http://www.bookrags.com/biography/henry-louis-le-chatelier-wsd/ | access-date = 2007-03-24}}</ref>

;1885:[[Eugen Goldstein]] names the [[cathode ray]], later discovered to be composed of electrons, and the [[canal ray]], later discovered to be positive hydrogen ions that had been stripped of their electrons in a [[cathode ray tube]].  These would later be named [[proton]]s.<ref>{{cite web | title = History of Chemistry | work = Intensive General Chemistry| publisher = Columbia University Department of Chemistry Undergraduate Program | url = http://www.columbia.edu/itc/chemistry/chem-c2507/navbar/chemhist.html | access-date = 2007-03-24}}</ref>

;1893:[[Alfred Werner]] discovers the octahedral structure of cobalt complexes, thus establishing the field of [[coordination chemistry]].<ref>{{cite web | title = Alfred Werner: The Nobel Prize in Chemistry 1913 | work = Nobel Lectures, Chemistry 1901–1921 | publisher = Elsevier Publishing Company | year = 1966 | url = http://nobelprize.org/nobel_prizes/chemistry/laureates/1913/werner-bio.html | access-date = 2007-03-24}}</ref>

;1894–1898: [[William Ramsay]] discovers the [[noble gases]], which fill a large and unexpected gap in the periodic table and led to models of chemical bonding.<ref>{{cite web | title = William Ramsay: The Nobel Prize in Chemistry 1904 | work = Nobel Lectures, Chemistry 1901–1921 | publisher = Elsevier Publishing Company | year = 1966 | url =  http://nobelprize.org/nobel_prizes/chemistry/laureates/1904/ramsay-bio.html | access-date = 2007-03-20}}</ref>

;1897:[[J. J. Thomson]] discovers the [[electron]] using the [[cathode ray tube]].<ref>{{cite book | chapter = Joseph John Thomson | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation | year = 2005 }}</ref>

;1898:[[Wilhelm Wien]] demonstrates that canal rays (streams of positive ions) can be deflected by magnetic fields, and that the amount of deflection is proportional to the [[mass-to-charge ratio]].  This discovery would lead to the [[analytical chemistry|analytical]] technique known as [[mass spectrometry]].<ref>{{cite web | title = Alfred Werner: The Nobel Prize in Physics 1911 | work = Nobel Lectures, Physics 1901–1921 | publisher = Elsevier Publishing Company | year = 1967 | url = http://nobelprize.org/nobel_prizes/physics/laureates/1911/wien-bio.html | access-date = 2007-03-24}}</ref>

;1898:[[Maria Sklodowska-Curie]] and [[Pierre Curie]] isolate [[radium]] and [[polonium]] from [[pitchblende]].<ref>{{cite book | chapter = Marie Sklodowska Curie | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation |year=2005}}</ref>

;c. 1900: [[Ernest Rutherford]] discovers the source of [[radioactivity]] as decaying atoms; coins terms for various types of radiation.<ref name=rutherford>{{cite web | title = Ernest Rutherford: The Nobel Prize in Chemistry 1908 | work = Nobel Lectures, Chemistry 1901–1921 | publisher = Elsevier Publishing Company | year = 1966 | url = http://nobelprize.org/nobel_prizes/chemistry/laureates/1908/rutherford-bio.html | access-date = 2007-02-28}}</ref>

==20th century==
;1903:[[Mikhail Semyonovich Tsvet]] invents [[chromatography]], an important analytic technique.<ref>{{cite encyclopedia | title = Tsvet, Mikhail (Semyonovich) | encyclopedia = Compton's Desk Reference | publisher = Encyclopædia Britannica | year = 2007 | url = http://deskreference.britannica.com/ebc/print?tocId=9381267 | archive-url = https://archive.today/20120630161359/http://deskreference.britannica.com/ebc/print?tocId=9381267 | url-status = dead | archive-date = 2012-06-30 | access-date = 2007-03-24 }}</ref>

;1904:[[Hantaro Nagaoka]] proposes an early [[Bohr model|nuclear model]] of the atom, where electrons orbit a dense massive nucleus.<ref name=physTL>{{cite web | title = Physics Time-Line 1900 to 1949 | publisher = Weburbia.com | url = http://www.weburbia.com/pg/hist3.htm | access-date = 2007-03-25 | url-status = dead | archive-url = https://web.archive.org/web/20070430031506/http://www.weburbia.com/pg/hist3.htm | archive-date = 2007-04-30 }}</ref>

;1905:[[Fritz Haber]] and [[Carl Bosch]] develop the [[Haber process]] for making [[ammonia]] from its elements, a milestone in industrial chemistry with deep consequences in agriculture.<ref>{{cite book | chapter = Fritz Haber | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation | year = 2005 }}</ref>

;1905:[[Albert Einstein]] explains [[Brownian motion]] in a way that definitively proves atomic theory.<ref>{{cite web |last=Cassidy |first=David |title=Einstein on Brownian Motion |publisher=The Center for History of Physics |year=1996 |url=http://www.aip.org/history/einstein/essay-brownian.htm |access-date=2007-03-25 |archive-date=2007-02-06 |archive-url=https://web.archive.org/web/20070206051254/http://www.aip.org/history/einstein/essay-brownian.htm |url-status=dead }}</ref>

;1907:[[Leo Hendrik Baekeland]] invents [[bakelite]], one of the first commercially successful plastics.<ref>{{cite book | chapter = Leo Hendrik Baekeland | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation | year = 2005 }}</ref>

[[File:Robert-millikan2.jpg|right|thumb|upright|[[Robert A. Millikan]] performed the oil drop experiment.]]
;1909:[[Robert Millikan]] measures the charge of individual electrons with unprecedented accuracy through the [[oil drop experiment]], confirming that all electrons have the same charge and mass.<ref>{{cite web | title = Robert A. Millikan: The Nobel Prize in Physics 1923 | work = Nobel Lectures, Physics 1922–1941 | publisher = Elsevier Publishing Company | year = 1965 | url = http://nobelprize.org/nobel_prizes/physics/laureates/1923/press.html | access-date = 2007-07-17}}</ref>

;1909:[[S. P. L. Sørensen]] invents the [[pH]] concept and develops methods for measuring acidity.<ref>{{cite book | chapter = Søren Sørensen | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation | year = 2005 }}</ref>

;1911:[[Antonius van den Broek]] proposes the idea that the elements on the periodic table are more properly organized by positive nuclear charge rather than atomic weight.<ref>{{cite web |last=Parker |first=David |title=Nuclear Twins: The Discovery of the Proton and Neutron |work=Electron Centennial Page |url=http://www.davidparker.com/janine/twins.html |access-date=2007-03-25}}</ref>

;1911:The first [[Solvay Conference]] is held in [[Brussels]], bringing together most of the most prominent scientists of the day.  Conferences in physics and chemistry continue to be held periodically to this day.<ref>{{cite web | title = Solvay Conference | publisher = Einstein Symposium | year = 2005 | url = http://www.bibalex.org/Einstein2005/About_Solvay.htm | access-date = 2007-03-28}}</ref>

;1911:Ernest Rutherford, [[Hans Geiger]], and [[Ernest Marsden]] perform the [[Geiger–Marsden experiment|gold foil experiment]], which proves the nuclear model of the atom, with a small, dense, positive nucleus surrounded by a diffuse [[electron cloud]].<ref name=rutherford/>

;1912:[[William Henry Bragg]] and [[William Lawrence Bragg]] propose [[Bragg's law]] and establish the field of [[X-ray crystallography]], an important tool for elucidating the crystal structure of substances.<ref name="autogenerated1">{{cite web | title = The Nobel Prize in Physics 1915 | work = Nobelprize.org | publisher = The Nobel Foundation | url = http://nobelprize.org/nobel_prizes/physics/laureates/1915/ | access-date = 2007-02-28}}</ref>

;1912:[[Peter Debye]] develops the concept of [[dipole|molecular dipole]] to describe asymmetric charge distribution in some molecules.<ref>{{cite web | title = Peter Debye: The Nobel Prize in Chemistry 1936 | work = Nobel Lectures, Chemistry 1922–1941 | publisher = Elsevier Publishing Company | year = 1966 | url = http://nobelprize.org/nobel_prizes/chemistry/laureates/1936/debye-bio.html | access-date = 2007-02-28}}</ref>
[[File:Bohr atom model.svg|thumb|right|180px|The Bohr model of the atom]]
;1913:[[Niels Bohr]] introduces concepts of [[quantum mechanics]] to atomic structure by proposing what is now known as the [[Bohr model]] of the atom, where electrons exist only in strictly defined [[Atomic orbital|orbitals]].<ref>{{cite web | title = Niels Bohr: The Nobel Prize in Physics 1922 | work = Nobel Lectures, Chemistry 1922–1941 | publisher = Elsevier Publishing Company | year = 1966 | url = http://nobelprize.org/nobel_prizes/physics/laureates/1922/bohr-bio.html | access-date = 2007-03-25}}</ref>

;1913:[[Henry Moseley]], working from Van den Broek's earlier idea, introduces concept of [[atomic number]] to fix inadequacies of Mendeleev's periodic table, which had been based on atomic weight.<ref>{{cite web |last=Weisstein |first=Eric W. |title=Moseley, Henry (1887–1915) |work=Eric Weisstein's World of Scientific Biography |publisher=Wolfram Research Products |year=1996 |url=http://scienceworld.wolfram.com/biography/Moseley.html |access-date=2007-03-25}}</ref>

;1913:[[Frederick Soddy]] proposes the concept of [[isotope]]s, that elements with the same chemical properties may have differing atomic weights.<ref>{{cite web | title = Frederick Soddy The Nobel Prize in Chemistry 1921  | work = Nobel Lectures, Chemistry 1901–1921 | publisher = Elsevier Publishing Company | year = 1966 | url = http://nobelprize.org/nobel_prizes/chemistry/laureates/1921/soddy-bio.html | access-date = 2007-03-25}}</ref>

;1913:[[J. J. Thomson]] expanding on the work of Wien, shows that charged subatomic particles can be separated by their mass-to-charge ratio, a technique known as [[mass spectrometry]].<ref>{{cite web | title = Early Mass Spectrometry | work = A History of Mass Spectrometry | publisher = Scripps Center for Mass Spectrometry | year = 2005 | url = http://masspec.scripps.edu/MSHistory/timelines/1897.php | access-date = 2007-03-26 |archive-url = https://web.archive.org/web/20070303134854/http://masspec.scripps.edu/MSHistory/timelines/1897.php <!-- Bot retrieved archive --> |archive-date = 2007-03-03}}</ref>

;1916:[[Gilbert N. Lewis]] publishes "The Atom and the Molecule", the foundation of [[valence bond theory]].<ref name=lewis>{{cite book | chapter = Gilbert Newton Lewis and Irving Langmuir | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation | year = 2005 }}</ref>

;1921:[[Otto Stern]] and [[Walther Gerlach]] establish concept of [[Spin (physics)|quantum mechanical spin]] in subatomic particles.<ref>{{cite web | title = Electron Spin | url = http://hyperphysics.phy-astr.gsu.edu/hbase/spin.html | access-date = 2007-03-26}}</ref>

;1923:Gilbert N. Lewis and [[Merle Randall]] publish ''Thermodynamics and the Free Energy of Chemical Substances'', first modern treatise on [[chemical thermodynamics]].<ref>{{cite web |last1=LeMaster |first1=Nancy |last2=McGann |first2=Diane |title=GILBERT NEWTON LEWIS: AMERICAN CHEMIST (1875–1946) |work=Woodrow Wilson Leadership Program in Chemistry |publisher=The Woodrow Wilson National Fellowship Foundation |year=1992 |url=http://www.woodrow.org/teachers/ci/1992/Lewis.html |access-date=2007-03-25 |url-status=dead |archive-url=https://web.archive.org/web/20070401163425/http://www.woodrow.org/teachers/ci/1992/Lewis.html |archive-date=2007-04-01 }}</ref>

;1923:Gilbert N. Lewis develops the electron pair theory of [[acid]]/[[base (chemistry)|base]] reactions.<ref name=lewis/>

;1924:[[Louis de Broglie]] introduces the wave-model of atomic structure, based on the ideas of [[wave–particle duality]].<ref>{{cite web | title = Louis de Broglie: The Nobel Prize in Physics 1929 | work = Nobel Lectures, Physics 1922–1941 | publisher = Elsevier Publishing Company | year = 1965 | url = http://nobelprize.org/nobel_prizes/physics/laureates/1929/broglie-bio.html | access-date = 2007-02-28}}</ref>

;1925:[[Wolfgang Pauli]] develops the [[Pauli exclusion principle|exclusion principle]], which states that no two electrons around a single nucleus may have the same quantum state, as described by four [[quantum numbers]].<ref>{{cite web | title = Wolfgang Pauli: The Nobel Prize in Physics 1945 | work = Nobel Lectures, Physics 1942–1962 | publisher = Elsevier Publishing Company | year = 1964 | url = http://nobelprize.org/nobel_prizes/physics/laureates/1945/pauli-bio.html | access-date = 2007-02-28}}</ref>

{{Image frame |content=<math>H(t) | \psi (t) \rangle = i \hbar \frac{d}{d t} | \psi (t) \rangle</math> |caption=The Schrödinger equation}}
;1926:[[Erwin Schrödinger]] proposes the [[Schrödinger equation]], which provides a mathematical basis for the wave model of atomic structure.<ref>{{cite web | title = Erwin Schrödinger: The Nobel Prize in Physics 1933 | work = Nobel Lectures, Physics 1922–1941 | publisher = Elsevier Publishing Company | year = 1965 | url = http://nobelprize.org/nobel_prizes/physics/laureates/1933/schrodinger-bio.html | access-date = 2007-02-28}}</ref>

;1927:[[Werner Heisenberg]] develops the [[uncertainty principle]] which, among other things, explains the mechanics of electron motion around the nucleus.<ref>{{cite web | title = Werner Heisenberg: The Nobel Prize in Physics 1932 | work = Nobel Lectures, Physics 1922–1941 | publisher = Elsevier Publishing Company | year = 1965 | url = http://nobelprize.org/nobel_prizes/physics/laureates/1932/heisenberg-bio.html | access-date = 2007-02-28}}</ref>

;1927:[[Fritz London]] and [[Walter Heitler]] apply quantum mechanics to explain covalent bonding in the hydrogen molecule,<ref>{{cite journal |last1=Heitler |first1=Walter |last2=London |first2=Fritz |year=1927 |title=Wechselwirkung neutraler Atome und homöopolare Bindung nach der Quantenmechanik |journal=Zeitschrift für Physik |volume=44 |issue= 6–7|pages=455–472 |bibcode=1927ZPhy...44..455H |doi=10.1007/BF01397394 |s2cid=119739102 }}</ref> which marked the birth of [[quantum chemistry]].<ref>Ivor Grattan-Guinness. ''Companion Encyclopedia of the History and Philosophy of the Mathematical Sciences''. Johns Hopkins University Press, 2003, p. 1266.; [[Jagdish Mehra]], [[Helmut Rechenberg]]. ''The Historical Development of Quantum Theory''. Springer, 2001, p. 540.</ref>

;1929: [[Linus Pauling]] publishes [[Pauling's rules]], which are key principles for the use of [[X-ray crystallography]] to deduce molecular structure.<ref name=pauling>{{cite web|title=Linus Pauling: The Nobel Prize in Chemistry 1954|work=Nobel Lectures, Chemistry 1942–1962|publisher=Elsevier|year=1964|url=http://nobelprize.org/nobel_prizes/chemistry/laureates/1954/pauling-bio.html|access-date=2007-02-28}}</ref>

;1931:[[Erich Hückel]] proposes [[Hückel's rule]], which explains when a planar ring molecule will have [[aromaticity|aromatic]] properties.<ref>{{cite web |last=Rzepa |first=Henry S. |title=The aromaticity of Pericyclic reaction transition states |publisher=Department of Chemistry, Imperial College London |url=http://www.ch.ic.ac.uk/rzepa/pericyclic/ |access-date=2007-03-26}}</ref>

;1931:[[Harold Urey]] discovers [[deuterium]] by [[fractional distillation|fractionally distilling]] liquid hydrogen.<ref>{{cite web | title = Harold C. Urey: The Nobel Prize in Chemistry 1934 | work = Nobel Lectures, Chemistry 1922–1941 | publisher = Elsevier Publishing Company | year = 1965 | url = http://nobelprize.org/nobel_prizes/chemistry/laureates/1934/urey-bio.html | access-date = 2007-03-26}}</ref>
[[File:Nylon6 and Nylon 66.png|thumb|right|180px|Model of two common forms of nylon]]
;1932:[[James Chadwick]] discovers the [[neutron]].<ref>{{cite web | title = James Chadwick: The Nobel Prize in Physics 1935 | work = Nobel Lectures, Physics 1922–1941 | publisher = Elsevier Publishing Company | year = 1965 | url = http://nobelprize.org/nobel_prizes/physics/laureates/1935/chadwick-bio.html | access-date = 2007-02-28}}</ref>

;1932–1934:Linus Pauling and [[Robert Mulliken]] quantify [[electronegativity]], devising the scales that now bear their names.<ref>{{cite journal |last=Jensen |first=William B.|author1-link=William B. Jensen |doi=10.1021/ed080p279 |title=Electronegativity from Avogadro to Pauling: II. Late Nineteenth- and Early Twentieth-Century Developments |journal=Journal of Chemical Education |year=2003 |volume=80 |issue=3 |page=279 |bibcode=2003JChEd..80..279J }}</ref>

;1935:[[Wallace Carothers]] leads a team of chemists at [[DuPont]] who invent [[nylon]], one of the most commercially successful synthetic polymers in history.<ref>{{cite book|chapter=Wallace Hume Carothers|title=Chemical Achievers: The Human Face of Chemical Sciences|publisher=Chemical Heritage Foundation|year=2005}}</ref>

;1937:[[Carlo Perrier]] and [[Emilio Segrè]] perform the first confirmed synthesis of [[technetium|technetium-97]], the first artificially produced element, filling a gap in the periodic table.  Though disputed, the element may have been synthesized as early as 1925 by [[Walter Noddack]] and others.<ref>{{cite web | title = Emilio Segrè: The Nobel Prize in Physics 1959 | work = Nobel Lectures, Physics 1942–1962 | publisher = Elsevier Publishing Company | year = 1965 | url = http://nobelprize.org/nobel_prizes/physics/laureates/1959/segre-bio.html | access-date = 2007-02-28}}</ref>

;1937:[[Eugene Houdry]] develops a method of industrial scale catalytic cracking of petroleum, leading to the development of the first modern oil refinery.<ref>{{cite book | chapter = Eugene Houdry | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation | year = 2005 }}</ref>

;1937:[[Pyotr Kapitsa]], [[John F. Allen (physicist)|John Allen]] and [[Don Misener]] produce supercooled [[helium|helium-4]], the first zero-viscosity [[superfluid]], a substance that displays quantum mechanical properties on a macroscopic scale.<ref>{{cite web | title = Pyotr Kapitsa: The Nobel Prize in Physics 1978 | work = Les Prix Nobel, The Nobel Prizes 1991 | publisher = Nobel Foundation | year = 1979 | url = http://nobelprize.org/nobel_prizes/physics/laureates/1978/kapitsa-bio.html | access-date = 2007-03-26}}</ref>

;1939:[[Otto Hahn]] and [[Lise Meitner]] discover the process of [[nuclear fission]] in [[uranium]].<ref>{{cite web | title = Otto Hahn: The Nobel Prize in Chemistry 1944 | work = Nobel Lectures, Chemistry 1942–1962 | publisher = Elsevier Publishing Company | year = 1964 | url = http://nobelprize.org/nobel_prizes/chemistry/laureates/1944/hahn-bio.html | access-date = 2007-04-07}}</ref>

;1939:Linus Pauling publishes ''The Nature of the Chemical Bond'', a compilation of a decades worth of work on [[chemical bonding]].  It is one of the most important modern chemical texts.  It explains [[orbital hybridization|hybridization theory]], [[covalent bonding]] and [[ionic bonding]] as explained through electronegativity, and [[resonance (chemistry)|resonance]] as a means to explain, among other things, the structure of [[benzene]].<ref name=pauling/>

;1940:[[Edwin McMillan]] and [[Philip H. Abelson]] identify [[neptunium]], the lightest and first synthesized [[transuranium element]], found in the products of uranium [[Nuclear fission|fission]].  McMillan would found a lab at [[University of California, Berkeley|Berkeley]] that would be involved in the discovery of many new elements and isotopes.<ref name=seaborg>{{cite book | chapter = Glenn Theodore Seaborg | title = Chemical Achievers: The Human Face of Chemical Sciences | publisher = Chemical Heritage Foundation | year = 2005 }}</ref>

;1941:[[Glenn T. Seaborg]] takes over McMillan's work creating new atomic nuclei.  Pioneers method of [[neutron capture]] and later through other [[nuclear reactions]].  Would become the principal or co-discoverer of nine new chemical elements, and dozens of new isotopes of existing elements.<ref name=seaborg/>

;1944 
:[[Robert Burns Woodward]] and [[William von Eggers Doering]] successfully synthesized of [[quinine]]. This achievement, characterized of fully artificial chemicals as source for synthesis process, opened an era called as "Woodwardian era" or "chemical era" when many drugs and chemicals, as well as [[organic synthesis]] methods invented. Due to the growth of chemical industry, many fields has grown, such as [[Pharmaceutical industry|drug industry]].<ref>{{Cite journal |last=Seeman |first=Jeffrey I. |date=2007 |title=The Woodward-Doering/Rabe-Kindler total synthesis of quinine: setting the record straight |journal=Angewandte Chemie International Edition |volume=46 |issue=9 |pages=1378–1413 |doi=10.1002/anie.200601551 |issn=1433-7851 |pmid=17294412|doi-access=free }}</ref>

;1945–1946: [[Felix Bloch]] and [[Edward Mills Purcell]] develop the process of [[nuclear magnetic resonance]], an [[analytical chemistry|analytical]] technique important in elucidating structures of molecules, especially in [[organic chemistry]].<ref>{{cite web | title = The Nobel Prize in Physics 1952 | work = Nobelprize.org | publisher = The Nobel Foundation | url = http://nobelprize.org/nobel_prizes/physics/laureates/1952/ | access-date = 2007-02-28}}</ref>

:[[Jacob A. Marinsky]], [[Lawrence E. Glendenin]], and [[Charles D. Coryell]] perform the first confirmed synthesis of [[Promethium]], filling in the last "gap" in the periodic table.<ref name="histofelem">{{cite web |title=History of the Elements of the Periodic Table |url=http://www.ausetute.com.au/elemhist.html |access-date=2007-03-26 |publisher=AUS-e-TUTE}}</ref>

;1951:Linus Pauling uses X-ray crystallography to deduce the [[secondary structure]] of proteins.<ref name=pauling/>

;1952:[[Alan Walsh (scientist)|Alan Walsh]] pioneers the field of [[atomic absorption spectroscopy]], an important [[Quantitative property|quantitative]] spectroscopy method that allows one to measure specific concentrations of a material in a mixture.<ref>{{cite web |last=Hannaford |first=Peter |title=Alan Walsh 1916–1998 |work=AAS Biographical Memoirs |publisher=Australian Academy of Science |url=http://www.science.org.au/academy/memoirs/walsh2.htm |access-date=2007-03-26 |archive-url=https://web.archive.org/web/20070224214248/http://www.science.org.au/academy/memoirs/walsh2.htm <!-- Bot retrieved archive --> |archive-date=2007-02-24}}</ref>

;1952:[[Robert Burns Woodward]], [[Geoffrey Wilkinson]], and [[Ernst Otto Fischer]] discover the structure of [[ferrocene]], one of the founding discoveries of the field of [[organometallic chemistry]].<ref name=woodward>{{cite journal |last1=Cornforth |first1=Lord Todd, John |title=Robert Burns Woodward. 10 April 1917-8 July 1979 |journal=Biographical Memoirs of Fellows of the Royal Society |volume=27 |issue= 6|pages=628–695  |jstor=198111 |date=November 1981 |doi=10.1098/rsbm.1981.0025 |last2=Cornforth |first2=J. |last3=T. |first3=A. R. |last4=C. |first4=J. W.|doi-access=free }} ''note: authorization required for web access.''</ref>

;1953:[[James D. Watson]] and [[Francis Crick]] propose the structure of [[DNA]], opening the door to the field of [[molecular biology]].<ref>{{cite web | title = The Nobel Prize in Medicine 1962 | work = Nobelprize.org | publisher = The Nobel Foundation | url = http://nobelprize.org/nobel_prizes/medicine/laureates/1962/ | access-date = 2007-02-28}}</ref>

;1957: [[Jens Skou]] discovers [[Na⁺/K⁺-ATPase]], the first ion-transporting enzyme.<ref>{{cite journal |last=Skou |first=Jens  |title=The influence of some cations on an adenosine triphosphatase from peripheral nerves. |journal=Biochim Biophys Acta |volume=23 |issue=2 |pages=394–401 |year=1957 |pmid=13412736 |doi=10.1016/0006-3002(57)90343-8|s2cid=32516710 }}</ref>

;1958:[[Max Perutz]] and [[John Kendrew]] use X-ray crystallography to elucidate a [[protein]] structure, specifically [[sperm whale]] [[myoglobin]].<ref>{{cite web | title = The Nobel Prize in Chemistry 1962 | work = Nobelprize.org | publisher = The Nobel Foundation | url = http://nobelprize.org/nobel_prizes/chemistry/laureates/1962/ | access-date = 2007-02-28}}</ref>

;1962:[[Neil Bartlett (chemist)|Neil Bartlett]] synthesizes [[xenon hexafluoroplatinate]], showing for the first time that the noble gases can form chemical compounds.<ref name="Neil Bartlett and the Reactive Noble Gases">{{cite web|title=Neil Bartlett and the Reactive Noble Gases|url=http://portal.acs.org/portal/PublicWebSite/education/whatischemistry/landmarks/bartlettnoblegases/index.htm|publisher=[[American Chemical Society]]|access-date=June 5, 2012|url-status=dead|archive-url=https://archive.today/20130112091550/http://portal.acs.org/portal/PublicWebSite/education/whatischemistry/landmarks/bartlettnoblegases/index.htm|archive-date=January 12, 2013}}</ref>

;1962:[[George Olah]] observes [[carbocation]]s via [[superacid]] reactions.<ref>G. A. Olah, S. J. Kuhn, W. S. Tolgyesi, E. B. Baker, J. Am. Chem. Soc. 1962, 84, 2733; G. A. Olah, lieu. Chim. (Bucharest), 1962, 7, 1139 (Nenitzescu issue); G. A. Olah, W. S. Tolgyesi, S. J. Kuhn, M. E. Moffatt, I. J. Bastien, E. B. Baker, J. Am. Chem. Soc. 1963, 85, 1328.</ref>

;1964:[[Richard R. Ernst]] performs experiments that will lead to the development of the technique of [[Fourier transform]] NMR.  This would greatly increase the sensitivity of the technique, and open the door for [[magnetic resonance imaging]] or MRI.<ref>{{cite web | title = Richard R. Ernst The Nobel Prize in Chemistry 1991 | work = Les Prix Nobel, The Nobel Prizes 1991 | publisher = Nobel Foundation | year = 1992 | url = http://nobelprize.org/nobel_prizes/chemistry/laureates/1991/ernst-autobio.html | access-date = 2007-03-27}}</ref>

;1965:Robert Burns Woodward and [[Roald Hoffmann]] propose the [[Woodward–Hoffmann rules]], which use the symmetry of [[molecular orbital]]s to explain the stereochemistry of chemical reactions.<ref name=woodward/>

;1966:[[Hitoshi Nozaki]] and [[Ryōji Noyori]] discovered the first example of [[asymmetric catalysis]] ([[hydrogenation]]) using a structurally well-defined [[chirality (chemistry)|chiral]] [[transition metal]] complex.<ref>H. Nozaki, S. Moriuti, H. Takaya, R. Noyori, Tetrahedron Lett. 1966, 5239;</ref><ref>H.
Nozaki, H. Takaya, S. Moriuti, R. Noyori, Tetrahedron 1968, 24, 3655.</ref>

;1970: [[John Pople]] develops the [[Gaussian (software)|Gaussian]] program greatly easing [[computational chemistry]] calculations.<ref>W. J. Hehre, W. A. Lathan, R. Ditchfield, M. D. Newton, and J. A. Pople, Gaussian 70 (Quantum Chemistry Program Exchange, Program No. 237, 1970).</ref>

;1971:[[Yves Chauvin]] offered an explanation of the reaction mechanism of [[olefin metathesis]] reactions.<ref>''Catalyse de transformation des oléfines par les complexes du tungstène. II. Télomérisation des oléfines cycliques en présence d'oléfines acycliques'' Die Makromolekulare Chemie Volume 141, Issue 1, Date: 9 February '''1971''', Pages: 161–176 Par Jean-Louis Hérisson, Yves Chauvin {{doi|10.1002/macp.1971.021410112}}</ref>

;1975:[[Karl Barry Sharpless]] and group discover a stereoselective [[oxidation]] reactions including [[Sharpless epoxidation]],<ref>{{cite journal | doi = 10.1021/ja00538a077 | volume=102 | title=The first practical method for asymmetric epoxidation | year=1980 | journal=Journal of the American Chemical Society | pages=5974–5976 | last1 = Katsuki | first1 = Tsutomu| issue=18 }}</ref><ref>Hill, J. G.; [[K. Barry Sharpless|Sharpless, K. B.]]; Exon, C. M.; Regenye, R. ''[[Org. Synth.]]'', Coll. Vol. 7, p.461 (1990); Vol. 63, p.66 (1985). ([http://www.orgsyn.org/orgsyn/prep.asp?prep=cv7p0461 Article])</ref> [[Sharpless asymmetric dihydroxylation]],<ref>{{cite journal | doi = 10.1021/ja00214a053 | volume=110 | title=Asymmetric dihydroxylation via ligand-accelerated catalysis | year=1988 | journal=Journal of the American Chemical Society | pages=1968–1970 | last1 = Jacobsen | first1 = Eric N.| issue=6 }}</ref><ref>{{cite journal | doi = 10.1021/cr00032a009 | volume=94 | title=Catalytic Asymmetric Dihydroxylation | year=1994 | journal=Chemical Reviews | pages=2483–2547 | last1 = Kolb | first1 = Hartmuth C.| issue=8 }}</ref><ref>Gonzalez, J.; Aurigemma, C.; Truesdale, L. ''[[Org. Synth.]]'', Coll. Vol. 10, p.603 (2004); Vol. 79, p.93 (2002). ([http://www.orgsyn.org/orgsyn/prep.asp?prep=v79p0093 Article])</ref> and [[Sharpless oxyamination]].<ref>{{cite journal | doi = 10.1021/ja00841a071 | volume=97 | title=New reaction. Stereospecific vicinal oxyamination of olefins by alkyl imido osmium compounds | year=1975 | journal=Journal of the American Chemical Society | pages=2305–2307 | last1 = Sharpless | first1 = K. Barry| issue=8 }}</ref><ref>{{cite journal | doi = 10.1021/ja00479a051 | volume=100 | title=Osmium-catalyzed vicinal oxyamination of olefins by N-chloro-N-argentocarbamates | year=1978 | journal=Journal of the American Chemical Society | pages=3596–3598 | last1 = Herranz | first1 = Eugenio| issue=11 }}</ref><ref>Herranz, E.; [[K. Barry Sharpless|Sharpless, K. B.]] ''[[Org. Synth.]], Coll.'' Vol. 7, p.375 (1990); Vol. 61, p.85 (1983). ([http://www.orgsyn.org/orgsyn/prep.asp?prep=cv7p0375 Article])</ref>
[[File:C60 Molecule.svg|thumb|right|upright|Buckminsterfullerene, C<sub>60</sub>]]
;1985:[[Harold Kroto]], [[Robert Curl]] and [[Richard Smalley]] discover [[fullerenes]], a class of large carbon molecules superficially resembling the [[geodesic dome]] designed by architect [[R. Buckminster Fuller]].<ref>{{cite web | title = The Nobel Prize in Chemistry 1996 | work = Nobelprize.org | publisher = The Nobel Foundation | url = http://nobelprize.org/nobel_prizes/chemistry/laureates/1996/ | access-date = 2007-02-28}}</ref>

;1991:[[Sumio Iijima]] uses [[electron microscopy]] to discover a type of cylindrical fullerene known as a [[carbon nanotube]], though earlier work had been done in the field as early as 1951.  This material is an important component in the field of [[nanotechnology]].<ref>{{cite web | title = Benjamin Franklin Medal awarded to Dr. Sumio Iijima, Director of the Research Center for Advanced Carbon Materials, AIST | publisher = National Institute of Advanced Industrial Science and Technology | year = 2002 | url = http://www.aist.go.jp/aist_e/topics/20020129/20020129.html | access-date = 2007-03-27 | url-status = dead | archive-url = https://web.archive.org/web/20070404214121/http://www.aist.go.jp/aist_e/topics/20020129/20020129.html | archive-date = 2007-04-04 }}</ref>

;1994:First [[Holton Taxol total synthesis|total synthesis of Taxol]]  by [[Robert A. Holton]] and his group.<ref>''First total synthesis of taxol 1.'' Functionalization of the B ring Robert A. Holton, Carmen Somoza, Hyeong Baik Kim, Feng Liang, Ronald J. Biediger, P. Douglas Boatman, Mitsuru Shindo, Chase C. Smith, Soekchan Kim, et al.; [[J. Am. Chem. Soc.]]; '''1994'''; 116(4); 1597–1598. [http://pubs.acs.org/doi/abs/10.1021/ja00083a066 DOI Abstract]</ref><ref>{{cite journal | doi = 10.1021/ja00083a067 | volume=116 | title=First total synthesis of taxol. 2. Completion of the C and D rings | year=1994 | journal=Journal of the American Chemical Society | pages=1599–1600  | last1 = Holton | first1 = Robert A.| issue=4 }}</ref><ref>{{cite journal | doi = 10.1021/ja00227a043 | volume=110 | title=A synthesis of taxusin | year=1988 | journal=Journal of the American Chemical Society | pages=6558–6560  | last1 = Holton | first1 = Robert A.| issue=19 }}</ref>

;1995:[[Eric Cornell]] and [[Carl Wieman]] produce the first [[Bose–Einstein condensate]], a substance that displays quantum mechanical properties on the macroscopic scale.<ref>{{cite web|title=Cornell and Wieman Share 2001 Nobel Prize in Physics |work=NIST News Release |publisher=National Institute of Standards and Technology |year=2001 |url=https://www.nist.gov/public_affairs/releases/n01-04.htm |access-date=2007-03-27 |url-status=dead |archive-url=https://web.archive.org/web/20070610080506/https://www.nist.gov/public_affairs/releases/n01-04.htm |archive-date=2007-06-10 }}</ref>

==See also==

* [[History of chemistry]]
* [[Nobel Prize in chemistry]]
* [[List of Nobel laureates in Chemistry]]
* [[Timeline of chemical elements discoveries]]

==References==
{{Reflist|30em}}

==Further reading==
* ''[https://www.calameo.com/read/0076312910bd4f10e26dc Crossing Oceans: Exchange of Products, Instruments, Procedures and Ideas in the History of Chemistry and Related Sciences]'', edited by Ana Maria Alfonso-Goldfarb, Walter Carnielli, Hasok Chang, Márcia H. M. Ferraz, & Silvia Waisse. São Paulo, Brazil: Coleção CLE/UNICAMP, 2015.
* [[John Servos|Servos, John W.]], [https://books.google.com/books?id=1UZjU2WfLAoC ''Physical chemistry from Ostwald to Pauling : the making of a science in America''], Princeton, N.J. : Princeton University Press, 1990. {{ISBN|0-691-08566-8}}

==External links==
*[http://scienceworld.wolfram.com/biography/ Eric Weisstein's World of Scientific Biography]
*[http://mattson.creighton.edu/HistoryGasChemistry.html History of Gas Chemistry]
*[http://nobelprize.org/nobel_prizes/lists/all/ list of all Nobel Prize laureates]
*[http://www.ausetute.com.au/elemhist.html History of Elements of the Periodic Table]
*[https://www.listserv.dfn.de/sympa/info/chem-hist  CHEM-HIST: International Mailing List for the History of Chemistry]
{{History of chemistry}}
{{Branches of chemistry}}

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[[Category:History of chemistry]]
[[Category:Lists of inventions or discoveries|Chemistry, timeline of]]