Editing Hydrogen (section)

=== 18th century ===
[[File:Portret van Robert Boyle, RP-P-OB-4578 (cropped).jpg|thumb|[[Robert Boyle]], who discovered the reaction between [[iron filings]] and dilute acids]]
In 1671, Irish scientist [[Robert Boyle]] discovered and described the reaction between [[iron]] filings and dilute [[acid]]s, which results in the production of hydrogen gas.<ref>{{Cite book |last=Boyle |first=R. |url=https://quod.lib.umich.edu/e/eebo2/A29057.0001.001?rgn=main;view=fulltext |title=Tracts written by the Honourable Robert Boyle containing new experiments, touching the relation betwixt flame and air, and about explosions, an hydrostatical discourse occasion'd by some objections of Dr. Henry More against some explications of new experiments made by the author of these tracts: To which is annex't, an hydrostatical letter, dilucidating an experiment about a way of weighing water in water, new experiments, of the positive or relative levity of bodies under water, of the air's spring on bodies under water, about the differing pressure of heavy solids and fluids |publisher=Printed for Richard Davis |year=1672 |pages=64–65}}</ref><ref>{{cite web
|first=M.
|last=Winter
|date=2007
|url=http://education.jlab.org/itselemental/ele001.html
|title=Hydrogen: historical information
|publisher=WebElements Ltd
|access-date=5 February 2008
|archive-url=https://web.archive.org/web/20080410102154/http://education.jlab.org/itselemental/ele001.html
|archive-date=10 April 2008
}}</ref>
Boyle did not note that the gas was inflammable, but hydrogen would play a key role in overturning the [[phlogiston theory]] of combustion.<ref name=Ramsay-1896>{{Cite book |last=Ramsay |first=W. |url=https://www.gutenberg.org/files/52778/52778-h/52778-h.htm |title=The gases of the atmosphere: The history of their discovery |publisher=Macmillan |year=1896 |pages=19}}</ref>

In 1766, [[Henry Cavendish]] was the first to recognize hydrogen gas as a discrete substance, by naming the gas from a [[metal-acid reaction]] "inflammable air". He speculated that "inflammable air" was in fact identical to the hypothetical substance "[[Phlogiston theory|phlogiston]]"<ref>{{cite book |last = Musgrave
 |first = A.
 |chapter = Why did oxygen supplant phlogiston? Research programmes in the Chemical Revolution
 |title = Method and appraisal in the physical sciences
 |series = The Critical Background to Modern Science, 1800–1905
 |editor = Howson, C.
 |year = 1976
 |publisher = Cambridge University Press
 |access-date = 22 October 2011
 |chapter-url = http://ebooks.cambridge.org/chapter.jsf?bid=CBO9780511760013&cid=CBO9780511760013A009
 |doi = 10.1017/CBO9780511760013
 |isbn = 978-0-521-21110-9
 |url-access = registration
 |url = https://archive.org/details/methodappraisali0000unse
}}</ref><ref name="cav766">{{cite journal|last1=Cavendish|first1=Henry|title=Three Papers, Containing Experiments on Factitious Air, by the Hon. Henry Cavendish, F. R. S.|journal=Philosophical Transactions|date=12 May 1766|volume=56|pages=141–184|jstor=105491|bibcode=1766RSPT...56..141C|doi=10.1098/rstl.1766.0019|doi-access=free}}</ref> and further finding in 1781 that the gas produces water when burned. He is usually given credit for the discovery of hydrogen as an element.<ref name="Nostrand">{{cite encyclopedia| title=Hydrogen| encyclopedia=Van Nostrand's Encyclopedia of Chemistry| pages=797–799| publisher=Wylie-Interscience| year=2005| isbn=978-0-471-61525-5}}</ref><ref name="nbb">{{cite book| last=Emsley| first=John| title=Nature's Building Blocks| publisher=Oxford University Press| year=2001| location=Oxford| pages=183–191| isbn=978-0-19-850341-5}}</ref>

[[File:Antoine-Laurent Lavoisier by Louis Jean Desire Delaistre (cropped).jpg|thumb|[[Antoine Lavoisier]], who identified the element that came to be known as hydrogen]]
In 1783, [[Antoine Lavoisier]] identified the element that came to be known as hydrogen<ref>{{cite book| last=Stwertka| first=Albert| title=A Guide to the Elements| url=https://archive.org/details/guidetoelements00stwe| url-access=registration| publisher=Oxford University Press| year=1996| pages=[https://archive.org/details/guidetoelements00stwe/page/16 16–21]| isbn=978-0-19-508083-4}}</ref> when he and [[Pierre-Simon Laplace|Laplace]] reproduced Cavendish's finding that water is produced when hydrogen is burned.<ref name="nbb" /> Lavoisier produced hydrogen for his experiments on mass conservation by treating metallic [[iron]] with a stream of H<sub>2</sub>O through an incandescent iron tube heated in a fire. Anaerobic oxidation of iron by the protons of water at high temperature can be schematically represented by the set of following reactions:
*{{chem2|Fe + H2O -> FeO + H2}}
*{{chem2|2Fe + 3 H2O -> Fe2O3 + 3 H2}}
*{{chem2|3Fe + 4 H2O -> Fe3O4 + 4 H2}}

Many metals react similarly with water leading to the production of hydrogen.<ref>{{Cite journal |last1=Northwood |first1=D. O. |last2=Kosasih |first2=U. |date=1983 |title=Hydrides and delayed hydrogen cracking in zirconium and its alloys |url=https://journals.sagepub.com/doi/full/10.1179/imtr.1983.28.1.92 |journal=International Metals Reviews |language=en |volume=28 |issue=1 |pages=92–121 |doi=10.1179/imtr.1983.28.1.92 |issn=0308-4590}}</ref>  In some situations, this H<sub>2</sub>-producing process is problematic as is the case of zirconium cladding on nuclear fuel rods.<ref>{{cite journal |doi=10.1016/j.jnucmat.2019.02.042 |title=Hydrogen in zirconium alloys: A review |date=2019 |last1=Motta |first1=Arthur T. |last2=Capolungo |first2=Laurent |last3=Chen |first3=Long-Qing |last4=Cinbiz |first4=Mahmut Nedim |last5=Daymond |first5=Mark R. |last6=Koss |first6=Donald A. |last7=Lacroix |first7=Evrard |last8=Pastore |first8=Giovanni |last9=Simon |first9=Pierre-Clément A. |last10=Tonks |first10=Michael R. |last11=Wirth |first11=Brian D. |author11-link=Brian Wirth|last12=Zikry |first12=Mohammed A. |journal=Journal of Nuclear Materials |volume=518 |pages=440–460 |bibcode=2019JNuM..518..440M }}</ref>