Editing Chalcogen (section)

===Periodic table placing===
[[File:Mendelejevs periodiska system 1871.png|thumb|upright=1.5|[[Dmitri Mendeleev]]'s periodic system proposed in 1871 showing oxygen, sulfur, selenium and tellurium part of his group VI]]

Three of the chalcogens (sulfur, selenium, and tellurium) were part of the discovery of [[Periodic table|periodicity]], as they are among a series of triads of elements in the same [[group (periodic table)|group]] that were noted by [[Johann Wolfgang Döbereiner]] as having similar properties.<ref name="The Disappearing Spoon"/> Around 1865 [[John Alexander Reina Newlands|John Newlands]] produced a series of papers where he listed the elements in order of increasing atomic weight and similar physical and chemical properties that recurred at intervals of eight; he likened such periodicity to the [[octave]]s of music.<ref>{{Cite journal |title = On Relations Among the Equivalents |author = Newlands, John A. R. |journal = Chemical News |volume = 10 |pages = 94–95 |date =20 August 1864 |url=http://web.lemoyne.edu/~GIUNTA/EA/NEWLANDSann.HTML |url-status=live |archive-url=https://web.archive.org/web/20110101073248/http://web.lemoyne.edu/~GIUNTA/EA/NEWLANDSann.HTML |archive-date=January 1, 2011 |access-date=November 25, 2013}}</ref><ref>{{cite journal |title = On the Law of Octaves |author = Newlands, John A. R. |journal = Chemical News |volume = 12 |page = 83 |date = 18 August 1865 |url=http://web.lemoyne.edu/~GIUNTA/EA/NEWLANDSann.HTML |url-status=live |archive-url=https://web.archive.org/web/20110101073248/http://web.lemoyne.edu/~GIUNTA/EA/NEWLANDSann.HTML |archive-date=January 1, 2011 |access-date=November 25, 2013}}</ref> His version included a "group b" consisting of oxygen, sulfur, selenium, tellurium, and [[osmium]].

[[File:Johann Wolfgang Döbereiner.jpg|thumb|upright|left|[[Johann Wolfgang Döbereiner]] was among the first to notice similarities between what are now known as chalcogens.]]

After 1869, [[Dmitri Mendeleev]] proposed his periodic table placing oxygen at the top of "group VI" above sulfur, selenium, and tellurium.<ref>{{cite journal|last=Mendelejew |first=Dimitri |year=1869 |title=Über die Beziehungen der Eigenschaften zu den Atomgewichten der Elemente |journal=Zeitschrift für Chemie |pages=405–406 |language=de}}</ref> [[Chromium]], [[molybdenum]], [[tungsten]], and [[uranium]] were sometimes included in this group, but they would be later rearranged as part of [[group 6 element|group VIB]]; uranium would later be moved to the [[actinide]] series. Oxygen, along with sulfur, selenium, tellurium, and later polonium would be grouped in ''group VIA'', until the group's name was changed to ''group 16'' in 1988.<ref>{{cite journal |last1=Fluck |first1=E.|year=1988 |title=New Notations in the Periodic Table |journal=[[Pure and Applied Chemistry|Pure Appl. Chem.]]|volume=60|pages=431–436|doi=10.1351/pac198860030431|url=http://www.iupac.org/publications/pac/1988/pdf/6003x0431.pdf |archive-url=https://ghostarchive.org/archive/20221010/http://www.iupac.org/publications/pac/1988/pdf/6003x0431.pdf |archive-date=2022-10-10 |url-status=live|issue=3 |s2cid=96704008|access-date=November 25, 2013}}</ref>