Editing Chalcogen (section)

===Atomic and physical===
Chalcogens show similar patterns in [[electron configuration]], especially in the outermost [[electron shell|shells]], where they all have the same number of [[valence electron]]s, resulting in similar trends in chemical behavior:

{| class="wikitable" style="white-space:nowrap;"
|-
!''[[Atomic number|Z]]'' !! [[Chemical element|Element]] !! [[Electron shell|Electrons per shell]]
|-
| 8 || Oxygen || 2, 6
|-
| 16 || Sulfur || 2, 8, 6
|-
| 34 || Selenium || 2, 8, 18, 6
|-
| 52 || Tellurium || 2, 8, 18, 18, 6
|-
| 84 || Polonium || 2, 8, 18, 32, 18, 6
|-
| 116 || Livermorium || 2, 8, 18, 32, 32, 18, 6 ''(predicted)''<ref name=Haire>{{Cite book |publisher= [[Springer Science+Business Media]] |location=Dordrecht, The Netherlands |bibcode=2011tcot.book.....M |doi =10.1007/978-94-007-0211-0 |editor1-last=Morss |editor1-first=Lester R. |editor2-last=Edelstein |editor2-first=Norman M. |editor3-last=Fuger| editor3-first=Jean |isbn =978-94-007-0210-3 |last1= Morss |first1= Lester R. |last2= Edelstein |first2= Norman M. |last3= Fuger |first3= Jean |year = 2011 |title = The Chemistry of the Actinide and Transactinide Elements }}</ref>
|}

{|class="wikitable" style="text-align:center"
|-
!Element !! Melting point<br />(°C)<ref name="Jackson2002" />
! Boiling point<br />(°C)<ref name="Jackson2002" />
!Density at STP<br />(g/cm<sup>3</sup>)<ref name="Jackson2002" />
|-
|Oxygen || −219 || −183 
|0.00143
|-
|Sulfur || 120 || 445 
|2.07
|-
|Selenium || 221 || 685 
|4.3
|-
|Tellurium || 450 || 988 
|6.24
|-
|Polonium || 254 || 962 
|9.2
|-
|Livermorium || 364–507 (predicted) || 762–862 (predicted) 
|14 (predicted)<ref name=Haire/>
|}

All chalcogens have six [[valence electron]]s. All of the solid, stable chalcogens are soft<ref>{{cite book|editor-last=Samsonov |editor-first=G. V. |chapter=Mechanical Properties of the Elements|doi=10.1007/978-1-4684-6066-7_7|isbn=978-1-4684-6066-7|chapter-url=http://ihtik.lib.ru/2011.08_ihtik_nauka-tehnika/2011.08_ihtik_nauka-tehnika_3560.rar|title=Handbook of the physicochemical properties of the elements|pages=387–446|publisher=IFI-Plenum|place=New York, USA|year=1968|url-status=dead|archive-url=https://web.archive.org/web/20150402123344/http://ihtik.lib.ru/2011.08_ihtik_nauka-tehnika/2011.08_ihtik_nauka-tehnika_3560.rar|archive-date=April 2, 2015|df=mdy-all}}</ref> and do not [[thermal conductivity|conduct heat]] well.<ref name="Jackson2002" /> [[Electronegativity]] decreases towards the chalcogens with higher atomic numbers. Density, melting and boiling points, and [[atomic radius|atomic]] and [[ionic radius|ionic radii]]<ref name="rsc">{{cite web |url=http://www.rsc.org/chemsoc/visualelements/pages/data/intro_groupvi_data.html |title=Visual Elements: Group 16 |publisher=Royal Society of Chemistry |access-date=November 25, 2013}}</ref> tend to increase towards the chalcogens with higher atomic numbers.<ref name="Jackson2002">{{cite book |last=Jackson |first=Mark |title=Periodic Table Advanced |publisher=Bar Charts Inc. |isbn=978-1-57222-542-8 |year=2002}}</ref>