Timeline of chemical elements discoveries
8200
226128608
2008-07-16T23:05:35Z
Nergaal
4761569
/* Unrecorded discoveries */
The discovery of the elements known to exist today is presented here in chronological order. The elements are listed generally in the order in which each was first defined as the pure element, as the exact date of discovery of most elements cannot be accurately defined. There are no written records for the discoveries of the first few elements that were known in antiquity.
Given is each element's [[list of elements by name|name]], [[atomic number]], year of first report, name of the discoverer, and some notes related to the discovery.
[[Image:Periodic table.svg|right|200px|thumb|[[Periodic Table]] of elements]]
==Unrecorded discoveries==
{| class="wikitable sortable width=150%"
|-
! [[Atomic number|Z]]<br>
! Name<br>
! Earliest use<br>
! Oldest<br>remaining<br>sample<br>
! Discoverers
! Place of<br>oldest<br>sample<br>
! class="unsortable" |Notes
|-
|29
|[[Copper]]
|9000 BCE
|6000 BCE
|[[Copper#History|Middle East]]
|[[Copper#History|Anatolia]]
|Copper was probably the first metal mined and crafted by man.<ref>http://www.rameria.com/inglese/history.html</ref> Earliest estimates of discovery of copper suggest around 9000 BCE in the Middle East. It is one of the most important materials to humans throughout the entire [[copper age|copper]] and [[bronze age]]s. Copper beads dating from 6000 BCE were found in [[Çatal Höyük]], [[Anatolia]].<ref>[http://www.csa.com/discoveryguides/copper/overview.php CSA - Discovery Guides, A Brief History of Copper]</ref>
|-
|79
|[[Gold]]
|before 6000 BCE
|5500 BCE
|[[Gold#History|Middle East]]
|Egypt
|Archaeologists suggest that first use of gold began with the first civilizations in the Middle East. It may have been the first metal used by humans. Oldest remaining gold jewelry is that in the tomb of Egyptian [[Queen Zer]].<ref>http://bullion.nwtmint.com/gold_history.php</ref><ref>http://indianvillage.com/turquoiseinfo.htm</ref>
|-
|82
|[[Lead]]
|7000 BCE
|3800 BCE
|[[Lead#History|Near East]]
|[[Abydos]]
|It is believed that lead smelting began at least 9000 years ago, and the oldest known artifact of lead is statuette found at the temple of [[Osiris]] on the site of Abydos dated circa 3800 BC.<ref>http://www.lead.org.au/lanv2n3/lanv2n3-22.html</ref> Lead was first purified and clearly differentiated from tin by medieval [[Alchemy and chemistry in Islam|Arabic chemists]]<ref name=El-Eswed>{{citation|title=Lead and Tin in Arabic Alchemy|first=Bassam I.|last=El-Eswed|journal=Arabic Sciences and Philosophy|year=2002|volume=12|pages=139–53|publisher=[[Cambridge University Press]]|doi=10.1017/S0957423902002060}}</ref>
|-
|47
|[[Silver]]
|before 5000 BCE
|~4000 BCE
|[[Silver#History|Asia Minor]]
|?
|Estimated to have happened to shortly after that of copper and gold.<ref>[http://elements.vanderkrogt.net/elem/ag.html 47 Silver]</ref><ref>[http://chemistry.about.com/od/elementfacts/a/silver.htm Silver Facts - Periodic Table of the Elements<!-- Bot generated title -->]</ref>
|-
|26
|[[Iron]]
|before 5000 BCE
|4000BCE
|[[History of ferrous metallurgy|?]]
|Egypt
|There is evidence that iron is known from before 5000 BCE.<ref>[http://elements.vanderkrogt.net/elem/fe.html 26 Iron<!-- Bot generated title -->]</ref> The oldest known iron objects used by humans are some beads made from meteorite iron, in Egypt, made about 4000BCE. Discovery of smelting around 3000 BCE lead to the prominence of use of iron for tools and weapons, which lead to the start of [[iron age]] around 1200 BCE.<ref>http://courses.wcupa.edu/jones/his101%5Cmisc%5Cpersia.htm</ref>
|-
|6
|[[Carbon]]
|3750 BCE
|?
|[[Carbon#History|Egyptians and Sumerians]]
|?
|Earliest known use of charcoal for the reduction of copper, zinc and tin ores in the manufacture of bronze, by the Egyptians and Sumerians.<ref>http://www.caer.uky.edu/carbon/history/carbonhistory.shtml</ref> [[Diamond]]s were probably known as early as 2500 BCE<ref>{{cite news | url = http://news.bbc.co.uk/2/hi/science/nature/4555235.stm | title = Chinese made first use of diamond | publisher = BBC News | date= 17 May 2005 | accessdate = 2007-03-21}}</ref> First true chemical analyzes were made in the 18th century CE,<ref>{{cite book |author=R-A Ferchault de Réaumur |last=Ferchault de Réaumur |first=R-A |year=1722 |title=L'art de convertir le fer forgé en acier, et l'art d'adoucir le fer fondu, ou de faire des ouvrages de fer fondu aussi finis que le fer forgé (English translation from 1956) |location=Paris, Chicago}}</ref> and in 1789 was listed by [[Antoine Lavoisier]] as an element.<ref>{{citeweb|author=Senese,Fred |date=September 9, 2009|url= http://antoine.frostburg.edu/chem/senese/101/inorganic/faq/discovery-of-carbon.shtm |title=Who discovered carbon?|publisher=Frostburg State University|accessdate=2007-11-24 }}</ref>
|-
|50
|[[Tin]]
|3500 BCE
|2000 BCE
|[[Tin#History|?]]
|?
|First smelt in combination with copper around 3500 BCE to produce [[bronze]] and [[brass]].<ref>http://elements.vanderkrogt.net/elem/sn.html</ref> Oldest artifacts date around 200 BCE.<ref>http://neon.mems.cmu.edu/cramb/Processing/history.html</ref> First purified and clearly differentiated from lead by medieval [[Alchemy and chemistry in Islam|Arabic chemists]] (ca. 700–1400 CE).<ref name=El-Eswed/>
|-
|16
|[[Sulfur]]
|before 2000 BCE
|?
|[[Sulfur#History|Chinese/Indians]]
|?
|First used at least 4000 years ago.<ref>[http://www.georgiagulfsulfur.com/history.htm Sulfur History<!-- Bot generated title -->]</ref> First identified as an element by [[Geber]] (ca. 800 CE).<ref name="r8"/> Also recognized as an element by [[Antoine Lavoisier]] in 1777.
|-
|80
|[[Mercury (element)|Mercury]]
|before 2000 BCE
|1500 BCE
||[[Mercury (element)#History|Chinese/Indians]]
|Egyptians
|Known to ancient Chinese and Hindus before 2000 BC, and found in Egyptian tombs dating from 1500 BCE.<ref>{{cite web | title=Mercury and the environment — Basic facts | publisher=''[[Environment Canada]], Federal Government of Canada'' | year=2004 | url=http://www.ec.gc.ca/MERCURY/EN/bf.cfm | accessdate=2008-03-27}}</ref> First identified as an element by [[Geber]] (ca. 800 CE).<ref name="r8">Strathern, Paul. (2000). Mendeleyev’s Dream – the Quest for the Elements. New York: Berkley Books.</ref>
|}
==Recorded discoveries==
{| class="sortable wikitable"
|-
! | Z<br>
! | Element<br>name<br>
! | First<br>observed or<br>predicted<br>
! | First<br>report of<br><small>characterization<br>(widely recognized)</small><br><ref name=D1/><ref name=D2/>
! | First<br>isolation<br><small>(widely known)</small><br>
! | First<br>observerer<br>
! | First person<br>to report characterization<br><small>(usually accepted discoverer)</small><br>
! | First<br>isolator<br>
! class="unsortable"| Notes
|-
|33
|[[Arsenic]]
|800 CE (ca.)
|
|800 CE (ca.)
|[[Geber]]
|
|[[Geber]]
|Discovered and isolated by [[Geber]] ca. 800 CE.<ref name=Sarton>[[George Sarton]], ''Introduction to the History of Science'' ([[cf.]] Dr. A. Zahoor and Dr. Z. Haq (1997), [http://www.cyberistan.org/islamic/Introl1.html ''Quotations From Famous Historians of Science''], [http://www.cyberistan.org Cyberistan])</ref><ref name=Ansari>{{citation|title=Electrocyclic reactions: from fundamentals to research|first1=Farzana Latif|last1=Ansari|first2=Rumana|last2=Qureshi|first3=Masood Latif|last3=Qureshi|year=1998|publisher=Wiley-VCH|isbn=3527297553|pages=2}}</ref> [[Albertus Magnus]] was the first European to isolate the element in 1250.<ref name=D1>{{cite web |url=http://www.chemicalelements.com/show/dateofdiscovery.html |title=Periodic Table: Date of Discovery|accessdate=2007-03-13}}</ref><ref name=D2>{{cite web |url=http://chemistry.about.com/library/das/aa030303a.htm |title=Timeline of Element Discovery|accessdate=2007-03-13}}</ref> In 1649, [[Johann Schröder]] published two ways of preparing elemental arsenic.
|-
|51
|[[Antimony]]
|800 (ca.)
|
|800 (ca.)
|[[Geber]]
|
|[[Geber]]
|Discovered and isolated by [[Geber]] ca. 800 CE.<ref name=Sarton/><ref name=Ansari/> [[Basilius Valentinus]] was the first European to describe the element around 1450.<ref name=D1/><ref name=D2/> First description of a procedure for isolating elemental antimony in 1540 by [[Vannoccio Biringuccio]].
|-
|83
|[[Bismuth]]
|800 (ca.)
|
|1753
|[[Geber]]
|
|[[Claude François Geoffroy]]
|Discovered by [[Geber]] ca. 800.<ref name=Ansari/><ref name=Briffault>[[Robert Briffault]] (1938), ''The Making of Humanity'', p. 195</ref> Later described in writings attributed to [[Basilius Valentinus]] around 1450.<ref name=D1/> Definitively identified by [[Claude François Geoffroy]] in 1753.<ref name=D2/>
|-
|30
|[[Zinc]]
|1526
|
|1746
|[[Paracelsus]]
|
|[[Andreas Sigismund Marggraf]]
|Identified as a unique metal by the alchemist Paracelsus but was extracted as a metal since antiquity (by [[History of metallurgy in the Indian subcontinent|Indian metallurgists]] before 100 BCE), but the true nature of this metal was not understood in ancient times.<ref>http://elements.vanderkrogt.net/elem/zn.html</ref>
|-
|15
|[[Phosphorus]]
|1669
|
|''1669''
|[[Hennig Brand]]
|
|''Hennig Brand''
|Prepared from urine, it was the first element to be chemically discovered.<ref>http://elements.vanderkrogt.net/elem/p.html</ref>
|-
|27
|[[Cobalt]]
|1732
|
|?
|[[Georg Brandt]]
|
|?
|Proved that the blue color of glass is due to a new kind of metal and not bismuth as thought previously.<ref>http://elements.vanderkrogt.net/elem/co.html</ref>
|-
|78
|[[Platinum]]
|1735
|
|''1735''
|[[Antonio de Ulloa]]
|
|''Antonio de Ulloa''
|First description of a metal found in [[South America]]n gold was in 1557 by [[Julius Caesar Scaliger]]. Ulloa published his findings in 1748, but [[Charles Wood (scientist)|Sir Charles Wood]] also investigated the metal in 1741. First reference to it as a new metal was made by [[William Brownrigg]] in 1750.<ref>http://elements.vanderkrogt.net/elem/pt.html</ref>
|-
|28
|[[Nickel]]
|1751
|
|''1751''
|[[Axel Fredrik Cronstedt]]
|
|''Axel Fredrik Cronstedt''
|By attempting to extract copper from the mineral known as "fake copper" (now known as [[niccolite]]).<ref>http://elements.vanderkrogt.net/elem/ni.html</ref>
|-
|12
|[[Magnesium]]
|1755
|
|1808
|[[Joseph Black]]
|
|[[Humphry Davy]]
|Black observed that ''magnesia alba'' (MgO) was not [[quicklime]] (CaO). Davy isolated it electrochemically from [[magnesia]].<ref>http://elements.vanderkrogt.net/elem/mg.html</ref>
|-
|1
|[[Hydrogen]]
|1766
|
|1500(ca.)
|[[Henry Cavendish]]
|
|[[Paracelsus]]
|Cavendish was the first to distinguish {{chem|H|2}} from other gases, although [[Paracelsus]] around 1500, Robert Boyle, and Joseph Priestley had observed its production by reacting strong acids with metals. Lavoisier named it in 1793.<ref>http://elements.vanderkrogt.net/elem/h.html</ref><ref>{{cite book|title=The Encyclopedia of the Chemical Elements|last=Andrews|first=A. C.|publisher=Reinhold Book Corporation|location=New York|year=1968|pages=272|editor=Clifford A. Hampel|chapter=Oxygen|id=LCCN 68-29938}}</ref>
|-
|8
|[[Oxygen]]
|1771
|
|''1771''
|[[Carl Wilhelm Scheele]]
|
|''Carl Wilhelm Scheele''
|Obtained from by heating [[mercuric oxide]] and [[nitrate]]s in 1771, but published his findings in 1777. [[Joseph Priestley]] also prepared this new ''air'' by 1774, but only Lavoisier recognized it as a true element and named it in 1777.<ref>http://elements.vanderkrogt.net/elem/o.html</ref><ref>{{cite book|title=The Encyclopedia of the Chemical Elements|last=Cook|first=Gerhard A.|coauthors=Lauer, Carol M.|publisher=Reinhold Book Corporation|location=New York|year=1968|pages=499–500|editor=Clifford A. Hampel|chapter=Oxygen|id=LCCN 68-29938}}</ref>
|-
|7
|[[Nitrogen]]
|1772
|
|''1772''
|[[Daniel Rutherford]]
|
|''Daniel Rutherford''
|He showed that the air in which animals had breathed, even after removal of the exhaled carbon dioxide, was no longer able to burn a candle. [[Carl Wilhelm Scheele]], [[Henry Cavendish]], and [[Joseph Priestley]] also studied the element about the same time, and Lavoisier named it in 1775-6.<ref>http://elements.vanderkrogt.net/elem/n.html</ref>
|-
|17
|[[Chlorine]]
|1774
|
|''1774''
|[[Carl Wilhelm Scheele]]
|
|''Carl Wilhelm Scheele''
|Obtained it from [[hydrochloric acid]], but thought it was on oxide. Only in 1808 Humphry Davy recognized it as an element.<ref>http://elements.vanderkrogt.net/elem/cl.html</ref>
|-
|25
|[[Manganese]]
|1770
|
|1774
|[[Torbern Olof Bergman]]
|
|[[Johan Gottlieb Gahn]]
|Distinguished [[pyrolusite]] as the calx of a new metal. [[Ignatius Gottfred Kaim]] also discovered the new metal in 1770 and Scheele in 1774 too. It was isolated by reduction of [[manganese dioxide]] with carbon.<ref>http://elements.vanderkrogt.net/elem/mn.html</ref>
|-
|56
|[[Barium]]
|1772
|
|1808
|[[Carl Wilhelm Scheele]]
|
|[[Humphry Davy]]
|Scheele distinguished a new earth ([[BaO]]) in [[pyrolusite]] and Davy isolated the metal by [[elecrolysis]].<ref>http://elements.vanderkrogt.net/elem/ba.html</ref>
|-
|42
|[[Molybdenum]]
|1778
|
|1781
|[[Carl Wilhelm Scheele]]
|
|[[Peter Jacob Hjelm]]
|Scheele recognised as a constituent of [[Molybdenite|molybdena]].<ref>http://elements.vanderkrogt.net/elem/mo.html</ref>
|-
|52
|[[Tellurium]]
|1782
|
|1795?
|[[Franz-Joseph Müller von Reichenstein]]
|
|[[Martin Heinrich Klaproth]]
|Muller observed it as an impurity in gold ores from Transylvania.<ref>http://elements.vanderkrogt.net/elem/te.html</ref>
|-
|74
|[[Tungsten]]
|1781
|
|1783
|[[Torbern Bergman]]
|
|[[Juan José Elhuyar|Juan José]] [[Fausto Elhuyar]]
|Bergman obtained from [[scheelite]] an oxide of a new element. The Elhuyars obtained [[tungstic acid]] from [[wolframite]] and reduced it with charcoal.<ref>http://elements.vanderkrogt.net/elem/w.html</ref>
|-
|38
|[[Strontium]]
|1787
|
|1808
|[[William Cruikshank]]
|
|Humphry Davy
|Cruikshank and [[Adair Crawford]] in 1790 concluded that [[strontianite]] contained a new earth. It was eventually isolated electrochemically in 1808 by Humphry Davy.<ref>http://elements.vanderkrogt.net/elem/sr.html</ref>
|-
!
!
!
!'''''1789'''''
!
!colspan=3|[[Antoine Lavoisier]]
!The first modern list of chemical elements, containing among others, 23 elements of those known then.<ref>http://homepage.mac.com/dtrapp/periodic.f/lavoisier.html</ref> He also redefined the term "element". Until him, all metals except mercury were not considered elements.
|-
|40
|[[Zirconium]]
|1789
|
|1824
|[[Martin Heinrich Klaproth]]
|
|[[Jöns Jakob Berzelius]]
|Klaproth identified the a new element in [[zirconia]].<ref>http://elements.vanderkrogt.net/chronology_index.html</ref><ref>{{Citation| contribution = Zirconium| year = 2007–2008| title = CRC Handbook of Chemistry and Physics| editor-last = Lide| editor-first = David R.| volume = 4| pages = 42| place = New York| publisher = CRC Press| id = 978-0-8493-0488-0}}</ref>
|-
|92
|[[Uranium]]
|1789
|
|1841
|[[Martin Heinrich Klaproth]]
|
|[[Eugène-Melchior Péligot]]
|Mistakenly identified an [[uranium oxide]] obtained from [[pitchblende]] as the element itself and named it after the recenty discovered planet [[Uranus (planet)|Uranus]].<ref>{{cite journal| title = Chemische Untersuchung des Uranits, einer neuentdeckten metallischen Substanz| author = [[Martin Heinrich Klaproth|M. H. Klaproth]]| journal = Chemische Annalen| volume = 2| issue =| year = 1789| pages = 387–403}}</ref><ref>{{cite journal| title = Recherches Sur L'Uranium| author = E.-M. Péligot| journal = Annales de chimie et de physique| volume = 5| issue = 5| year = 1842| pages = 5–47| url =http://gallica.bnf.fr/ark:/12148/bpt6k34746s/f4.table}}</ref>
|-
|22
|[[Titanium]]
|1791
|
|1825
|[[William Gregor]]
|
|[[Jöns Jakob Berzelius]]
|Gregor found an oxide of a new metal in [[ilmenite]] and [[Martin Heinrich Klaproth]] independently discovered the element in [[rutile]] in 1795 and named it. Pure metallic form was obtained only in 1910 by [[Matthew A. Hunter]].<ref>{{cite web|title=Titanium|url=http://periodic.lanl.gov/elements/22.html|date=2004|accessdate=2006-12-29| publisher=[[Los Alamos National Laboratory]]}}</ref><ref>{{cite book |title=''The Encyclopedia of the Chemical Elements'' |year=1968 |author=Barksdale, Jelks |publisher=[[Reinhold Book Corporation]] |location=[[Skokie, Illinois]] |pages=732-38 "Titanium"|id=LCCCN 68-29938}}</ref>
|-
|39
|[[Yttrium]]
|1794
|
|1840
|[[Johan Gadolin]]
|
|[[Carl Gustav Mosander]]
|Discovered in [[gadolinite]], but Mosander showed later that it contained more elements.<ref>{{cite journal|url=http://books.google.com/books?id=VV5KAAAAMAAJ&pg=PA46&lpg=PA46&dq=Yttrium+discovery&source=web&ots=kIrp-JqrS0&sig=Vjpm3O79VUAN-FiVRKaSmuCalbg&hl=en&sa=X&oi=book_result&resnum=9&ct=result|journal=Kongl. Vet. Acad. Handl.|volume=XV|pages=137 | doi = 10.1103/| doi_brokendate = 2008-06-25 | title = Introduction to the Rarer Elements}}</ref><ref>{{citejournal|year=1796|journal=Crell Anal.|volume=I|pages=313 | title =. }}</ref>
|-
|24
|[[Chromium]]
|1797
|
|1798
|[[Louis Nicolas Vauquelin]]
|
|''Louis Nicolas Vauquelin''
|Discovered and isolated from [[crocoite]].<ref>http://elements.vanderkrogt.net/elem/cr.html</ref>
|-
|4
|[[Beryllium]]
|1798
|
|1828
|Nicolas-Louis Vauquelin
|
|[[Friedrich Wöhler]] and [[Antoine Bussy]]
|Vauquelin discovered the oxide in [[beryl]] and emerald, and Klaproth suggested the present name around 1808.<ref>http://elements.vanderkrogt.net/elem/be.html</ref>
|-
|23
|[[Vanadium]]
|1801
|
|1830
|[[Andrés Manuel del Río]]
|
|[[Nils Gabriel Sefström]]
|Río found the metal in [[vanadinite]] but retracted the claim after [[Hippolyte Victor Collet-Descotils]] disputed it. Sefström isolated and named it, and later it was shown that Río had been right in the first place.<ref>http://elements.vanderkrogt.net/elem/v.html</ref>
|-
|41
|[[Niobium]]
|1801
|
|1864
|[[Charles Hatchett]]
|
|[[Christian Wilhelm Blomstrand]]
|Hatchett found the element in [[columbite]] ore and named it ''columbium''. [[Heinrich Rose]] proved in 1844 that the element is distinct from tantalum, and renamed it ''niobium'' which was officially accepted in 1949.<ref>http://elements.vanderkrogt.net/elem/ni.html</ref>
|-
|73
|[[Tantalum]]
|1802
|
|?
|[[Anders Gustaf Ekeberg]]
|
|?
|Ekeberg found another element in minerals similar to [[columbite]] and in 1844, Heinrich Rose proved that it was distinct from niobium.<ref>http://elements.vanderkrogt.net/elem/ta.html</ref>
|-
|46
|[[Palladium]]
|1802
|
|''1802''
|[[William Hyde Wollaston]]
|
|''William Hyde Wollaston''
|Wollaston discovered it in samples of platinum from South America, but did not publish his results immediately. He had intended to name it after the newly discovered [[asteroid]], [[Ceres (dwarf planet)|Ceres]], but by the time he published his results in 1804, cerium had taken that name. Wollaston named it after the more recently discovered asteroid [[2 Pallas|Pallas]].<ref>http://elements.vanderkrogt.net/elem/pd.html</ref>
|-
|58
|[[Cerium]]
|1803
|
|1839
|[[Martin Heinrich Klaproth]]; [[Jöns Jakob Berzelius]] and [[Wilhelm Hisinger]]
|
|[[Carl Gustaf Mosander]]
|Berzelius and Hisinger discovered the element in [[ceria]] and named it after the newly discovered [[asteroid]] (then considered a planet), [[Ceres (dwarf planet)|Ceres]]. Klaproth discovered it simultaneously and independently in some tantalum samples. Mosander proved later that the samples of all three researchers had at least another element in it, [[lathanum]].<ref>http://elements.vanderkrogt.net/elem/ce.html</ref>
|-
|76
|[[Osmium]]
|1803
|
|''1803''
|[[Smithson Tennant]]
|
|''Smithson Tennant''
|Tennant had been working on samples of South American platinum in parallel with Wollaston and discovered two new elements, which he named osmium and iridium.<ref>http://elements.vanderkrogt.net/elem/os.html</ref>
|-
|77
|[[Iridium]]
|1803
|
|''1803''
|[[Smithson Tennant]]
|
|''Smithson Tennant''
|Tennant had been working on samples of South American platinum in parallel with Wollaston and discovered two new elements, which he named osmium and iridium, and published the iridium results in 1804.<ref>http://elements.vanderkrogt.net/elem/ir.html</ref>
|-
|45
|[[Rhodium]]
|1804
|
|''1804''
|[[William Hyde Wollaston]]
|
|''William Hyde Wollaston''
|Wollaston discovered and isolated it from crude platinum samples from South America.<ref>http://elements.vanderkrogt.net/elem/rh.html</ref>
|-
|19
|[[Potassium]]
|1807
|
|''1807''
|[[Humphry Davy]]
|
|''Humphry Davy''
|Davy discovered it by using [[electrolysis]] on [[potash]].<ref>http://elements.vanderkrogt.net/elem/k.html</ref>
|-
|11
|[[Sodium]]
|1807
|
|''1807''
|[[Humphry Davy]]
|
|''Humphry Davy''
|Davy discovered it a few days after potassium, by using [[electrolysis]] on [[soda]].<ref>http://elements.vanderkrogt.net/elem/na.html</ref>
|-
|20
|[[Calcium]]
|1808
|
|''1808''
|[[Humphry Davy]]
|
|''Humphry Davy''
|Davy discovered the metal by [[electrolysis]] of [[quicklime]].<ref>http://elements.vanderkrogt.net/elem/na.html</ref>
|-
|5
|[[Boron]]
|1808
|
|1808
|[[Joseph Louis Gay-Lussac]] & [[Louis Jacques Thénard]]
|
|[[Humphry Davy]]
|On June 30, 1808, Lussac and Thénard announced a new element in [[boric acid|sedative salt]], and nine days later Davy announced the isolation of metallic boron.<ref>http://elements.vanderkrogt.net/elem/b.html</ref>
|-
|53
|[[Iodine]]
|1811
|
|''1811''
|[[Bernard Courtois]]
|
|''Bernard Courtois''
|Courtois discovered it in the ashes of [[sea weed]].<ref>http://elements.vanderkrogt.net/elem/i.html</ref>
|-
|3
|[[Lithium]]
|1817
|
|''1817''
|[[Johan August Arfwedson]]
|
|''Johan August Arfwedson''
|Arwerdson discovered the alkali in [[petalite]].<ref>http://elements.vanderkrogt.net/elem/li.html</ref>
|-
|48
|[[Cadmium]]
|1817
|
|''1817'
|[[Karl Samuel Leberecht Hermann|K.S.L Hermann]], [[Friedrich Stromeyer|F. Stromeyer]] &[[J.C.H. Roloff]]
|
|''K.S.L Hermann, F. Stromeyer, J.C.H. Roloff''
|All three found an unknown metal in a sample of [[zinc oxide]] from Silesia, but the name that Stromeyer gave became the accepted one.<ref>http://elements.vanderkrogt.net/elem/cd.html</ref>
|-
|34
|[[Selenium]]
|1817
|
|''1817''
|[[Jöns Jakob Berzelius]] & [[Johann Gottlieb Gahn]]
|
|''J.J.Berzelius & J.G.Gahn''
|While working with lead they discovered a substance that they thought it is tellurium, and after realizing it is different.<ref>http://elements.vanderkrogt.net/elem/se.html</ref>
|-
|32
|[[Silicon]]
|1824
|
|''1824''
|[[Jöns Jakob Berzelius]]
|
|''J.J.Berzelius''
|[[Humphry Davy]] thought in 1800 that [[silica]] is an element, not an compound, and in 1808 suggested the present name. In 1811 Louis-Joseph Gay-Lussac and Louis-Jacques Thénard probably prepared impure silicon, but Berzelius is credited with the discovery for obtaining the pure element in 1824.<ref>http://elements.vanderkrogt.net/elem/si.html</ref>
|-
|13
|[[Aluminium]]
|1825
|
|''1825''
|[[Hans Christian Ørsted]]
|
|''H.C.Ørsted''
|[[Antoine Lavoisier]] predicted in 1787 that [[alumine]] is the oxide of an undiscovered element, and in 1808 [[Humphry Davy]] tried to decompose it, and although failed, suggested the present name. [[Hans Christian Ørsted]] was the first to isolate metallic aluminum in 1825.<ref>http://elements.vanderkrogt.net/elem/al.html</ref>
|-
|35
|[[Bromine]]
|1825
|
|''1825''
|[[Antoine Jérôme Balard|A.J.Balard]],[[Leopold Gmelin|L.Gmelin]]
|
|''A.J.Balard & L.Gmelin''
|They both discovered the element in the Autumn of 1825, and published the results next year.<ref>http://elements.vanderkrogt.net/elem/br.html</ref>
|-
|90
|[[Thorium]]
|1829
|
|?
|[[Jöns Jakob Berzelius]]
|
|?
|Berzelius obtained the oxide of a new earth in [[thorite]].<ref>http://elements.vanderkrogt.net/elem/th.html</ref>
|-
|57
|[[Lanthanum]]
|1838
|
|?
|[[Carl Gustaf Mosander|C.G.Mosander]]
|
|?
|Mosander found a new element in samples of [[ceria]] and published his results in 1842, but later, he showed that this [[lathana]] contained four more elements.<ref>http://elements.vanderkrogt.net/elem/la.html</ref>
|-
|68
|[[Erbium]]
|1842
|
|?
|[[Carl Gustaf Mosander|C.G.Mosander]]
|
|?
|Mosander managed to split the old [[yttria]] into yttria proper and [[erbia]], and later [[terbia]] too.<ref>http://elements.vanderkrogt.net/elem/er.html</ref>
|-
|65
|[[Terbium]]
|1842
|
|''1842''
|[[Carl Gustaf Mosander|C.G.Mosander]]
|
|''C.G.Mosander''
|In 1842 Mosander split [[yttria]] into two more earths, [[erbia]] and [[terbia]]<ref>http://elements.vanderkrogt.net/elem/tb.html</ref>
|-
|44
|[[Ruthenium]]
|1807
|
|1807
|[[Jedrzej Sniadecki|J.Sniadecki]]
|
|J.Sniadecki
|Sniadecki isolated the element in 1807 but his work was not ratified. [[Gottfried Wilhelm Osann]] thought thought he found three new metals in Russian platinum samples, and in 1844, [[Karl Karlovich Klaus]] confirmed that there was a new element. The latter is usually recognized as the discoverer of the element.<ref>http://elements.vanderkrogt.net/elem/ru.html</ref>
|-
|55
|[[Caesium]]
|1860
|
|1882
|[[Robert Bunsen|R.W.Bunsen]] and [[Gustav Kirchhoff|G.R.Kirchhoff]]
|
|[[Carl Setterberg]]
|Bunsen and Kirchhoff were the first to suggest finding new elements by [[spectrum analysis]]. They discovered caesium by its two blue [[emission line]]s in a sample of [[Dürkheim]] [[mineral water]].<ref>http://elements.vanderkrogt.net/elem/cs.html</ref> The pure metal was eventually isolated in 1962 by Setterberg.<ref>http://www.chem.shef.ac.uk/chm131-2001/chb01jms/caesium.html</ref>
|-
|37
|[[Rubidium]]
|1861
|
|?
|[[Robert Bunsen|R.W.Bunsen]] and [[Gustav Kirchhoff|G.R.Kirchhoff]]
|
|[[Hevesy]]
|Bunsen and Kirchhoff discovered it just a few months after caesium, by observing new spectral lines in the mineral [[lepidolite]]. Bunsen never obtained a pure sample of the metal, which was later obtained by Hervesy.<ref>http://elements.vanderkrogt.net/elem/rb.html</ref>
|-
|81
|[[Thallium]]
|1861
|
|1862
|[[William Crookes]]
|
|[[Claude-Auguste Lamy]]
|Shortly after the discovery of rubidium, Crookes found a new green line in a selenium sample and later that year, Lamy found the element to be metallic.<ref>http://elements.vanderkrogt.net/elem/tl.html</ref>
|-
|49
|[[Indium]]
|1863
|
|1867
|[[Ferdinand Reich|F.Reich]] and [[Hieronymous Theodor Richter|H.T.Richter]]
|
|T.Richter
|Riach and Richter First identified it in [[sphalerite]] by its birght indigo-blue spectroscopic emission line. Richter isolated the metal several years later.<ref>http://elements.vanderkrogt.net/elem/in.html</ref>
|-
|2
|[[Helium]]
|1868
|
|1895
|[[Pierre Janssen|P.Janssen]]& [[Joseph Norman Lockyer|J.N.Lockyer]]
|
|[[Sir William Ramsay|W.Ramsay]], [[Per Theodor Cleve|P.T.Cleve]]& [[Nils Langlet|N.Langlet]]
|Janssen and Lockyer observed independently a yellow spectral line in the solar spectrum that did not match any other element.
Years later, Ramsay, Cleve, and Langlet observed independently the element trapped in [[clevite]] about the same time.<ref>http://elements.vanderkrogt.net/elem/he.html</ref>
|-
!
!
!
!
!'''''1869'''''
!colspan=3 |<center> [[Mendeleev]]
!Mendeleev arranges the 66 elements known at that time into the first modern periodic table
|-
|31
|[[Gallium]]
|1875
|
|?
|[[Paul Emile Lecoq de Boisbaudran|P.E.L.de Boisbaudran]]
|
|''P.E.L.de Boisbaudran''
|Boisbaudran observed on a Pyrenea [[blende]] sample some emission lines corresponding to the eka-aluminum that was predicted by[[Mendeleev's predicted elements|predicted]] by [[Mendeleev]] in 1871 and subsequently isolated the element by electrolysis.<ref>http://elements.vanderkrogt.net/elem/ga.html</ref>
|-
|70
|[[Ytterbium]]
|1878
|
|?
|[[Jean Charles Galissard de Marignac|J.C.G. de Marignac]]
|
|?
|In October 22, 1878, Marignac reported splitting [[terbia]] in two new earths, terbia proper and [[ytterbia]].<ref>http://elements.vanderkrogt.net/elem/yb.html</ref>
|-
|67
|[[Holmium]]
|1878
|
|?
|[[Marc Delafontaine|M.Delafontaine]] ??[[Jacques-Louis Soret]] and [[Per Teodor Cleve]]??
|
|?
|Delafontaine found it in [[samarskite]] and next year, Per Teodor Cleve split Marignac's [[erbia]] into erbia proper and two new elements, thulium and holmium.<ref>http://elements.vanderkrogt.net/elem/ho.html</ref>
|-
|69
|[[Thulium]]
|1879
|
|''1879''
|[[Per Teodor Cleve|P.T.Cleve]]
|
|''P.T.Cleve''
|Cleve split Marignac's [[erbia]] into erbia proper and two new elements, thulium and holmium.<ref>http://elements.vanderkrogt.net/elem/tm.html</ref>
|-
|21
|[[Scandium]]
|1879
|
|''1879''
|[[Lars Fredrik Nilson|L.F.Nilson]]
|
|''L.F.Nilson''
|Nilson split Marignac's [[ytterbia]] into pure one and a new element that matched [[Mendeleev's predicted elements|1871 Mendeleev's predicted]] eka-boron.<ref>http://elements.vanderkrogt.net/elem/sc.html</ref>
|-
|62
|[[Samarium]]
|1879
|
|''1879''
|[[Paul Emile Lecoq de Boisbaudran|P.E.L. de Boisbaudran]]
|
|'P.E.L. de Boisbaudran''
|Boisbaudran noted a new earth in [[samarskite]] and named it after the mineral.<ref>http://elements.vanderkrogt.net/elem/sm.html</ref>
|-
|64
|[[Gadolinium]]
|1880
|
|1886
|[[Jean Charles Galissard de Marignac]]
|
|[[François Lecoq de Boisbaudran]]
|Marignac initially observed the new earth in [[terbia]] and later, Bouisbaudran obtained a pure sample from [[samarskite]].<ref>http://elements.vanderkrogt.net/elem/gd.html</ref>
|-
|59
|[[Praseodymium]]
|1885
|
|?
|[[Carl Auer von Welsbach|C.A.von Welsbach]]
|
|?
|Von Welsbach discovered two new distinct elements in [[ceria]]: praseodymium and neodymium.<ref>http://elements.vanderkrogt.net/elem/pr.html</ref>
|-
|60
|[[Neodymium]]
|1885
|
|?
|[[Carl Auer von Welsbach|C.A.von Welsbach]]
|
|?
|Von Welsbach discovered two new distinct elements in [[ceria]]: praseodymium and neodymium.<ref>http://elements.vanderkrogt.net/elem/nd.html</ref>
|-
|66
|[[Dysprosium]]
|1886
|
|?
|[[Paul Emile Lecoq de Boisbaudran]]
|
|?
|De Boisbaudran found a new earth in [[erbia]].<ref>http://elements.vanderkrogt.net/elem/nd.html</ref>
|-
|32
|[[Germanium]]
|1886
|
|?
|[[Clemens Winkler|C.A.Winkler]]
|
|?
|In February 1886 Winkler found in [[argyrodite]] the eka-silicon that [[Mendeleev's predicted elements|Mendeleev had predicted in 1871]].<ref>http://elements.vanderkrogt.net/elem/ge.html</ref>
|-
|9
|[[Fluorine]]
|1886
|
|''1886''
|[[Henri Moissan]]
|
|''H.Moissan''
|Lavoisier predicted an element obtained from [[fluorhydric acid]] and between 1812 and 1886 many researchers tried to obtain this element. It was eventually isolated by Moissan.<ref>http://elements.vanderkrogt.net/elem/f.html</ref>
|-
|18
|[[Argon]]
|1894
|
|''1894''
|[[John Strutt, 3rd Baron Rayleigh|Lord Rayleigh]] & [[William Ramsay|W.Ramsay]]
|
|''Lord Rayleigh & W.Ramsay''
|They discovered the gas by comparing the molecular weights of nitrogen prepared by [[liquefaction]] from air and nitrogen prepared by chemical means. It is the first noble gas to be isolated.<ref>http://elements.vanderkrogt.net/elem/ar.html</ref>
|-
|36
|[[Krypton]]
|1898
|
|1898
|Sir [[William Ramsay]] & [[Morris W. Travers]]
|
|''W.Ramsay & M.W.Travers''
|On May 30, 1898, Ramsay separated a third noble gas from liquid argon by difference in boiling point.<ref>http://elements.vanderkrogt.net/elem/ne.html</ref>
|-
|10
|[[Neon]]
|1898
|
|1898
|Sir [[William Ramsay]] & [[Morris W. Travers]]
|
|''W.Ramsay & M.W.Travers''
|In June 1898 Ramsay separated a new noble gas from liquid argon by difference in boiling point.<ref>http://elements.vanderkrogt.net/elem/ne.html</ref>
|-
|54
|[[Xenon]]
|1898
|
|1898
|Sir [[William Ramsay]] & [[Morris W. Travers]]
|
|''W.Ramsay & M.W.Travers''
|On July 12, 1898 Ramsay separated a third noble gas within three weeks, from liquid argon by difference in boiling point.<ref>http://elements.vanderkrogt.net/elem/xe.html</ref>
|-
|84
|[[Polonium]]
|1898
|
|1902
|[[Pierre Curie]] and [[Marie Curie]]
|
|[[Willy Marckwald]]
|In an experiment done on July 13, 1898, the Curies noted an increased radioactivity in the uranium obtained from [[pitchblende]] which they assigned to an unknown element.<ref>http://elements.vanderkrogt.net/elem/po.html</ref>
|-
|88
|[[Radium]]
|1898
|
|1902
|[[Pierre Curie]] and [[Marie Curie]]
|
|Marie Curie
|The Curies reported on December 26, 1898, a new element different from polonium, which Marie later isolated from [[uraninite]].<ref>http://elements.vanderkrogt.net/elem/ra.html</ref>
|-
|86
|[[Radon]]
|1898
|
|1910
|[[Friedrich Ernst Dorn]]
|
|[[William Ramsay]] and [[Robert Whytlaw-Gray]]
|Dorn discovered a radioactive gas resulting from the radioactive decay of radium, isolated later by Ramsay and Gray.<ref>{{cite journal|title=Discovery of Radon|journal=[[Nature (journal)|Nature]]|volume=179|issue=4566|page=912|date=May 1957|author=Partington, J. R.}}</ref><ref>{{cite journal | title = La densité de l’emanation du radium | author = Ramsay, W.; Gray, R. W. | journal = Comptes rendus hebdomadaires des seances de l'Academie des sciences | volume = 151 | pages = 126–128 | year = 1910 | url = http://gallica.bnf.fr/ark:/12148/bpt6k31042/f126.table }}</ref>
|-
|89
|[[Actinium]]
|1899
|
|''1899''
|[[André-Louis Debierne|A.-L.Debierne]]
|
|''A.-L.Debierne''
|Debierne obtained from pitchblende a substance that had similar properties to thorium.<ref>http://elements.vanderkrogt.net/elem/ac.html</ref>
|-
|63
|[[Europium]]
|1896
|
|1901
|[[Eugene Demarcay]]
|
|Eugene Demarcay
|Demarçay found spectral lines of a new element in Lecoq's samarium, and separated this element several years later.<ref>http://elements.vanderkrogt.net/elem/eu.html</ref>
|-
|71
|[[Lutetium]]
|1906
|
|''1906''
|[[Georges Urbain]] & [[Carl Auer von Welsbach]]
|
|''G. Urbain & C.A. von Welsbach''
|Urbain and von Welsbach proved independently that the old [[ytterbium]] did also contain a new element.<ref>http://elements.vanderkrogt.net/elem/lu.html</ref>
|-
|75
|[[Rhenium]]
|1908
|
|''1908''
|[[Masataka Ogawa]]
|
|''Masataka Ogawa''
|Ogawa found it in [[thorianite]] but assigned it is element 43 instead of 75 and named it ''nipponium''. <ref>http://www.maik.ru/abstract/radchem/0/radchem0535_abstract.pdf</ref> In 1922 [[Walter Noddack]], [[Ida Eva Tacke]] and [[Otto Berg]] announced its separation from [[gadolinite]] and gave it the present name. <ref>http://elements.vanderkrogt.net/elem/rh.html</ref>
|-
|72
|[[Hafnium]]
|1911
|
|1922
|[[Georges Urbain]] & [[ Vladimir Ivanovich Vernadskij]]
|
|[[Dirk Coster]] and [[Georg von Hevesy]]
|Urbain claimed to have found the element in rare-earth residues, while [[Vernadskij]] independently found it in [[orthite]]. Neither clamis were confirmed due to the War. After it, Coster and Hevesy found it by X-ray spectroscopic analysis in Norwegian zircon.<ref>http://elements.vanderkrogt.net/elem/hf.html</ref> It is the last stable element to be discovered.
|-
|91
|[[Protactinium]]
|1913
|
|?
|[[Otto H. Göhring]] and [[Kasimir Fajans]]
|
|?
|The two obtained the first isotope of this element that had been [[Mendeleev's predicted elements|predicted by Mendeleev in 1871]] as a member of the natural decay of <sup>238</sup>U.<ref>http://elements.vanderkrogt.net/elem/pa.html</ref> Originally isolated in 1900 by [[William Crookes]].<ref> {{cite book | last = Emsley | first = John | title = Nature's Building Blocks | edition = (Hardcover, First Edition) | publisher = [[Oxford University Press]] | date = 2001 | pages = page 347 | id = ISBN 0198503407 }}</ref>
|-
|43
|[[Technetium]]
|1937
|
|''1937''
|[[Carlo Perrier]] and [[Emilio Segrè]]
|
|''C.Perrier and E.Segrè''
|The two discovered a new element in a molybdenum that was used in a [[cyclotrone]], the first [[synthetic element]] to be discovered. It had been [[Mendeleev's predicted elements|predicted by Mendeleev in 1871]] as eka-manganese.<ref>http://elements.vanderkrogt.net/elem/tc.html</ref><ref>''History of the Origin of the Chemical Elements and Their Discoverers'', Individual Element Names and History, "Technetium"</ref>
|-
|87
|[[Francium]]
|1939
|
|''1939''
|[[Marguerite Perey]]
|
|''M.Perey''
|Perey discovered it as a decay product of <sup>227</sup>Ac.<ref>http://elements.vanderkrogt.net/elem/fr.html</ref> Francium is the last element to be discovered in nature, rather than synthesized in the lab, although some of the "synthetic" elements that were discovered later (plutonium, neptunium, astatine) were eventually found in trace amounts in nature as well.
|-
|85
|[[Astatine]]
|1940
|
|?
|[[Dale R. Corson]], [[K.R.Mackenzie]], [[Emilio Segrè]]
|
|?
|Obtained by bombarding bismuth with alpha particles.<ref>http://elements.vanderkrogt.net/elem/at.html</ref> Later determined to occur naturally in minuscule quantitites (<25 grams in earth's crust).
|-
|93
|[[Neptunium]]
|1940
|
|?
|[[Edwin McMillan|E.M. McMillan]] & [[Philip H. Abelson]]
|
|?
|Obtained by irradiating uranium with neutrons, it is the first [[transuranium element]] discovered.<ref>http://elements.vanderkrogt.net/elem/np.html</ref>
|-
|94
|[[Plutonium]]
|1940-1
|
|?
|[[Glenn T. Seaborg]], [[Arthur C. Wahl]], [[Joseph W. Kennedy]], [[Edwin M. McMillan]]
|
|?
|Prepared by bombardment of uranium with deuterons.<ref>http://elements.vanderkrogt.net/elem/pu.html</ref>
|-
|95
|[[Americium]]
|1944
|
|?
|[[Glenn T. Seaborg]], [[Ralph A. James]], [[Leon O. Morgan]], and [[Albert Ghiorso]]
|
|?
|Prepared by irradiating plutonium with neutrons during the [[Manhattan Project]].<ref>http://elements.vanderkrogt.net/elem/am.html</ref>
|-
|96
|[[Curium]]
|1944
|
|?
|[[Glenn T. Seaborg]], [[Ralph A. James]], and [[Albert Ghiorso]]
|
|?
|Prepared by bombarding plutonium with alpha particles during the [[Manhattan Project]]<ref>http://elements.vanderkrogt.net/elem/cm.html</ref>
|-
|61
|[[Promethium]]
|1942
|
|1945
|[[Chien Shiung Wu]], [[Emilio G. Segrè]], and [[Hans Albrecht Bethe]]
|
|[[Charles D. Coryell]], [[Jacob A. Marinsky]], [[Lawrence E. Glendenin]], [[Harold G. Richter]]
|It was probably first prepared in 1942 by bombarding neodymium and praseodymium with neurons, but separation of the element could not be carried out. Isolation was performed under the [[Manhattan Project]] in 1945.<ref>http://elements.vanderkrogt.net/elem/pr.html</ref>
|-
|97
|[[Berkelium]]
|1949
|
|?
|[[Stanley G. Thompson]], [[Albert Ghiorso]], & [[Glenn T. Seaborg]]
|
|?
|Created by bombardment of americium with alpha particles.<ref>http://elements.vanderkrogt.net/elem/bk.html</ref>
|-
|98
|[[Californium]]
|1950
|
|?
|[[Stanley G. Thompson]], [[Kenneth Street, Jr.]], [[Albert Ghiorso]], and [[Glenn T. Seaborg]]
|
|?
|Bombardment of curium with alpha particles.<ref>http://elements.vanderkrogt.net/elem/cf.html</ref>
|-
|99
|[[Einsteinium]]
|1952
|
|1952
|[[Albert Ghiorso]] et. al ([[Argonne Laboratory]], [[Los Alamos Laboratory]], and [[University of California]])
|
|
|Formed in the first thermonuclear explosion in November 1952, by irradiation of uranium with neutronsand kept secret for several years.<ref>http://elements.vanderkrogt.net/elem/ei.html</ref>
|-
|100
|[[Fermium]]
|1952
|
|?
|[[Albert Ghiorso]] et. al ([[Argonne Laboratory]], [[Los Alamos Laboratory]], and [[University of California]])
|
|
|Formed in the first thermonuclear explosion in November 1952, by irradiation of uranium with neutrons and kept secret for several years.<ref>http://elements.vanderkrogt.net/elem/fm.html</ref>
|-
|101
|[[Mendelevium]]
|1955
|
|?
|[[Albert Ghiorso]], [[Bernard G. Harvey], [[Gregory R. Choppin]], [[Stanley G. Thompson]], and [[Glenn T. Seaborg]]
|
|?
|Prepared by bombardment of einsteinium with helium.<ref>http://elements.vanderkrogt.net/elem/md.html</ref>
|-
|102
|[[Nobelium]]
|1958
|
|?
|[[Albert Ghiorso]], [[Torbjørn Sikkeland]], [[J.R. Walton]], and [[Glenn T. Seaborg]]
|
|?
|First prepared by bombardment of curium with carbon atoms.<ref>http://elements.vanderkrogt.net/elem/no.html</ref>
|-
|103
|[[Lawrencium]]
|1961
|
|?
|[[Albert Ghiorso]], [[Torbjørn Sikkeland]], [[Almon E. Larsh]], and [[Robert M. Latimer]]
|
|?
|First prepared by bombardment of californium with boron atoms.<ref>http://elements.vanderkrogt.net/elem/lw.html</ref>
|-
|104
|[[Rutherfordium]]
|1964
|
|?
|[[Georgy Nikolaevich Flerov]] et. al at [[Joint Institute for Nuclear Research|JINR in Dubna]]
|
|?
|Prepared by bombardment of plutonium with neon atoms.<ref>http://elements.vanderkrogt.net/elem/rf.html</ref>
|-
|105
|[[Dubnium]]
|1968
|
|?
|[[Georgy Nikolaevich Flerov]] et. al at [[Joint Institute for Nuclear Research|JINR in Dubna]]
|
|?
|By bombardment of americium with neon atoms.<ref>http://elements.vanderkrogt.net/elem/db.html</ref>
|-
|106
|[[Seaborgium]]
|1974
|
|?
|[[Albert Ghiorso]] et. al in [[University of California, Berkeley]]
|
|?
|Collisions of californium-249 with oxygen atoms.<ref>http://elements.vanderkrogt.net/elem/sg.html</ref>
|-
|107
|[[Bohrium]]
|1981
|
|?
|[[Gottfried Münzenberg]] et. al [[Gesellschaft für Schwerionenforschung|GSI in Darmstadt]]
|
|?
|Obtained by bombarding bismuth with chromium.<ref>http://elements.vanderkrogt.net/elem/bh.html</ref>
|-
|109
|[[Meitnerium]]
|1982
|
|?
|[[Gottfried Münzenberg]], [[Peter Armbruster]] et. al [[Gesellschaft für Schwerionenforschung|GSI in Darmstadt]]
|
|?
|Bombardment of bismuth with iron atoms.<ref>http://elements.vanderkrogt.net/elem/mt.html</ref>
|-
|108
|[[Hassium]]
|1984
|
|?
|[[Gottfried Münzenberg]], [[Peter Armbruster]] et. al at [[Gesellschaft für Schwerionenforschung|GSI in Darmstadt]]
|
|?
|Bombardment of lead with iron atoms<ref>http://elements.vanderkrogt.net/elem/hs.html</ref>
|-
|110
|[[Darmstadtium]]
|1994
|
|?
|[[Sigurd Hofmann]], et al at [[Gesellschaft für Schwerionenforschung|GSI in Darmstadt]]
|
|?
|Bombardment of lead with nickel.<ref>http://elements.vanderkrogt.net/elem/ds.html</ref>
|-
|111
|[[Roentgenium]]
|1994
|
|?
|[[Sigurd Hofmann]], et al at [[Gesellschaft für Schwerionenforschung|GSI in Darmstadt]]
|
|?
|Bombardment of bismuth with nickel.<ref>http://elements.vanderkrogt.net/elem/rg.html</ref>
|}
==Unconfirmed discoveries==
{| class="sortable wikitable"
|-
! | Z<br>
! | Name<br>
! | Discovery<br>year<br>
! | Discoverer<br>
! class="unsortable"| Notes
|-
|112
|[[Ununbium]]
|1996
|[[S. Hofmann]], [[V. Ninov]] et al, [[Gesellschaft für Schwerionenforschung|GSI]]
|
|-
|114
|[[Ununquadium]]
|1999
|[[Joint Institute for Nuclear Research]] in [[Dubna]]
|<ref>{{cite journal | last = Oganessian | first = Yu. Ts. | coauthors = ''et al.'' | year = 1999 | month = October | title = Synthesis of Superheavy Nuclei in the <sup>48</sup>Ca + <sup>244</sup>Pu Reaction | journal = Physical Review Letters | volume = 83 | pages = 3154 | doi = 10.1103/PhysRevLett.83.3154 | url = http://link.aps.org/abstract/PRL/v83/p3154 }}</ref>
|-
| 116
|[[Ununhexium]]
|2000
|[[Joint Institute for Nuclear Research]] in [[Dubna]]
|<ref>{{cite journal | last = Oganessian | first = Yu. Ts. | coauthors = ''et al.'' | year = 2000 | title = Observation of the decay of <sup>292</sup>116 | journal = Physical Review C | volume = 63 | pages = 011301 | doi = 10.1103/PhysRevC.63.011301 | url = http://link.aps.org/abstract/PRC/v63/e011301 }}</ref>
|-
| 118
|[[Ununoctium]]
|2002
| [[Joint Institute for Nuclear Research]] in Dubna and [[Lawrence Livermore National Laboratory]]
|<ref>{{cite journal | last = Oganessian | first = Yu. Ts. | coauthors = ''et al.'' | year = 2006 | title = Synthesis of the isotopes of elements 118 and 116 in the <sup>249</sup>Cf and <sup>245</sup>Cm+<sup>48</sup>Ca fusion reactions | journal = Physical Review C | volume = 74 | pages = 044602 | doi = 10.1103/PhysRevC.74.044602 | url = http://link.aps.org/abstract/PRC/v74/e044602 }}</ref>
|-
| 113
|[[Ununtrium]]
|2003
| [[Joint Institute for Nuclear Research]] in Dubna and [[Lawrence Livermore National Laboratory]]
|<ref name="113+115">{{cite journal | last = Oganessian | first = Yu. Ts. | coauthors = ''et al.'' | year = 2005 | title = Synthesis of elements 115 and 113 in the reaction <sup>243</sup>Am + <sup>48</sup>Ca | journal = Physical Review C | volume = 72 | pages = 034611 | doi = 10.1103/PhysRevC.72.034611 | url = http://link.aps.org/abstract/PRC/v72/e034611 }}</ref>
|-
| 115
|[[Ununpentium]]
|2003
| [[Joint Institute for Nuclear Research]] in Dubna and [[Lawrence Livermore National Laboratory]]
|<ref name="113+115" />
|-
| 122
|''[[Unbibium]]''
|''2008''
| [[Hebrew University of Jerusalem]]<ref>[http://arxiv.org/abs/0804.3869 [0804.3869] Evidence for a long-lived superheavy nucleus with atomic mass number A=292 and atomic number Z=~122 in natural Th<!-- Bot generated title -->]</ref>
| '''Disputed claim:'''A group led by [[Amnon Marinov]] at the Hebrew University of Jerusalem claims to have found single atoms of unbibium in naturally occurring thorium deposits at a concentration of between 10<sup>-11</sup> and 10<sup>-12</sup>.<ref>[http://arxivblog.com/?p=385 the physics arXiv blog » Blog Archive » First superheavy element found in nature<!-- Bot generated title -->]</ref> If this is accurate, unbibium would be the first naturally occurring element to be discovered in nature since [[Francium]].
|-
|-
|}
==See also==
* [[Periodic table]]
* [[Elements song]]
* [[Ytterby]]
* [[Classical element]]
==References==
{{reflist|2}}
==External links==
*[http://www.ausetute.com.au/elemhist.html History of Elements of the Periodic Table]
*[http://chemistry.about.com/library/weekly/aa030303a.htm Timeline of Element Discoveries]
{{PeriodicTablesFooter}}
[[Category:History of chemistry]]
[[Category:History of physics]]
[[Category:Lists of chemical elements|Discovery]]
[[Category:Discoverers of chemical elements|*]]
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[[af:Ontdekking van die chemiese elemente]]
[[ar:تاريخ الكيمياء]]
[[ca:Història dels elements químics]]
[[cy:Rhestr elfennau yn nhrefn eu darganfyddiad]]
[[fa:کشف عناصر شیمیایی]]
[[fr:Histoire de la découverte des éléments chimiques]]
[[id:Penemuan unsur kimia]]
[[it:Scoperta degli elementi chimici]]
[[ja:化学元素発見の年表]]
[[pl:Historia odkryć pierwiastków]]
[[pt:Descoberta dos elementos químicos]]
[[ru:Хронология открытия химических элементов]]