Talk:Chalcogen

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Meaning of chalcogen[edit]

what is the origin of the word Chalcogen?

Found it. "Ore former". Corrected the page and added the ref I used. --ES2

Hey guys: according to http://en.wikipedia.org/wiki/Copper#History chalkos means copper! (added by some one else)

According to my very ancient dictionary of classical Greek Chalkos does mean copper. According to the source cited for this statement, the person who coined the term did intend it to mean 'ore former', but this seems to me to be a piece of bad etymology, probably by some one who did not know Greek. NB please sign your contributions on talk pages! See also my comment under Talk:copper Peterkingiron 22:55, 7 July 2006 (UTC)
Wilhelm Blitz and Werner Fischer came up with the names
[1] Palantini (talk) 04:02, 13 October 2008 (UTC)

Hello. I am a Greek physicist. Chalkos (in Greek "χαλκός") does mean copper and not ore. I looked for it in many Greek dictionaries (e.g. Mpampiniotis' and Triantafilidis' dictionaries). The word in ancient Greek had the same meaning as in modern Greek (the metal copper) so reference [1] wrong. The Greek word for ore is "ορυκτό" (orikto) or "μετάλλευμα" (metalevma).

Chalkos certainly means copper, but the article is talking about chalcogen. "gen" refers to genesis, I presume. So the whole word refers to the origin of copper, to the ore that "creates" the copper, itself containing the chalcogen elements.--Wickey-nl (talk) 15:29, 3 May 2010 (UTC)

I expanded the etymology out into a whole section. Let me know if anyone still has a problem with it. —Keenan Pepper 21:17, 3 May 2010 (UTC)

Beside the necessity to translate greek in latin, there is no reference for the second part of the name.--Wickey-nl (talk) 13:15, 4 May 2010 (UTC)
Uh, I don't understand what you mean by "translate greek into latin". The Latin word for copper is aes or cuprum, but what does that have to do with anything?
As for γιγνομαι, I just took that from Halogen#Etymology. That part actually comes from a large group of related Greek words, so you might see other sources say γενος or -γενες or whatever. They're all correct. —Keenan Pepper 19:40, 4 May 2010 (UTC)
Sorry, I meant it should be translated into latin alphabet, so in western alphabet. Thus gígnomai. By the way, that term is not found in the reference. My etymological dictionary says gen comes from gennan = produce. The German article says from γεννώ = erzeugen, produce. --Wickey-nl (talk) 12:02, 5 May 2010 (UTC)

The Oxford English Dictionary website, oed.com, gives the etymology as

[< CHALCO- comb. form + -GEN comb. form, after HALOGEN n. Cf. earlier CHALCOGENIDE n.]

and for chalcogenide,

[< CHALCO- comb. form + -GEN comb. form + -IDE suffix, after German Chalkogenid (W. Klemm & H. U. von Vogel 1934, in Zeitschr. f. anorg. u. allgemeine Chem. 219 45).]

I'll provide temporary access to the etymology of -gen: http://www.benjamin-mills.com/Wikipedia/-gen.png.

Ben (talk) 14:33, 5 May 2010 (UTC)

Hello again, the same Greek physicist. You have done great work here.

The word γίγνομαι (gignome) means give birth to but it also has a wider meaning. It is an old greek (καθαρεύουσα) and ancient greek word still in use although in modern greek we use the word γεννάω or γεννώ. Γεννάν (gennan) means they give birth. In the article you now mention: "and because the word χαλκός in ancient Greek was associated with metals and metal-bearing rock in general (because copper, and its alloy bronze, was one of the first metals to be used by humans)." I think (but I am not sure) that in classical ancient Greek (5th century BC) χαλκός is copper and its alloy, μέταλλο (metalo) is metal and σίδηρος (sidiros) is iron. What you mention about the interpretation of the word χαλκός as metal in general is probably true for the bronze age (much before the 10th century BC). The problem probably originates, as already mentioned, from the person who coined the term the first place so now we have to use bad etymology. —Preceding unsigned comment added by 188.4.21.242 (talk) 17:23, 7 May 2010 (UTC)

If I understand well, genes is the root of geinomai, gignomai, gennan, gignere (give birth to). Compare the English word gene genus.
The fault would be, that the word genes itself as suffix is not capable of meaning "that which produces" [2]. May be because producer and product are exchanged???--Wickey-nl (talk) 10:16, 8 May 2010 (UTC)
(Greek physicist: see sign-button above)


Color for chalcogens[edit]

I have come up with a color for the chalcogens.







Chalcogens

—Preceding unsigned comment added by Wd930 (talkcontribs)

This is one of the most bizarre comments I've ever seen. You've "come up with a color for the chalcogens", and that color is apparently white. Bwuh? —Keenan Pepper 04:11, 5 December 2010 (UTC)

GA Review[edit]

This review is transcluded from Talk:Chalcogen/GA1. The edit link for this section can be used to add comments to the review.

Reviewer: Jasper Deng (talk · contribs) 20:13, 22 January 2013 (UTC)

GA review (see here for what the criteria are, and here for what they are not)

I might want to see more formal prose.

  1. It is reasonably well written.
    a (prose): b (MoS for lead, layout, word choice, fiction, and lists):
    The prose fails to impress. "Thus the chalcogens bear copper" is inaccurate, for example, and the prose doesn't flow as well as I hope (though I understand that you are describing an entire element group. Also, I see quite a few typos (19 th century, for instance).
    Comment. Typos fixed. King Jakob C 23:14, 22 January 2013 (UTC)
    I still see instances of saying livermorium is made in nuclear reactors - it is made in particle accelerators. Also, I might again want to see a better flow in the article (if possible, if not it's not a big issue). "Not much is known about polonium's properties, but it is thought to be a metal" - I would try to make mention of the fact that this is disputed. Not much otherwise.--Jasper Deng (talk) 00:45, 1 February 2013 (UTC)
    Fixed. King Jakob C 01:33, 1 February 2013 (UTC)
  2. It is factually accurate and verifiable.
    a (reference section): b (citations to reliable sources): c (OR):
    "Thus the chalcogens bear copper" is probably meant to mean that they tend to combine with copper, but this statement as-is is definitely wrong. In addition, livermorium is made in particle accelerators, not nuclear reactors. Also, I see two bare references that should be converted to full citations.
    Comment. I fixed a few of the not-so-great sentences and phrases (including the thing about particle accelerators/nuclear reactors), and removed (or commented out) some of the uncited stuff. Which references are bare references? King Jakob C 23:14, 22 January 2013 (UTC)
    References 6-9, 19, 21, 36, and 38 have incomplete citations. I generally use the ProveIt gadget to do citations, see your user preferences if you'd like to use it - it'll make it easy to fill out full citations.--Jasper Deng (talk) 23:32, 22 January 2013 (UTC)
    Which sources aren't reliable? King Jakob C 15:30, 29 January 2013 (UTC)
    It's not about their reliability. It's about the completeness of their citations. Normally an on-hold lasts only 1 week, but I will give an extension to 10 days from the original date of the review to fix these issues (until 1 February). Unfortunately the GA will have to fail if these issues aren't addressed by then.--Jasper Deng (talk) 05:00, 31 January 2013 (UTC)
    OK, I fixed most of the references, but I can't fix references 3 and 9, because they don't list an author.King Jakob C 16:30, 31 January 2013 (UTC)
    The author is not mandatory in that case, but the citation should still be complete (even without the author).--Jasper Deng (talk) 20:31, 31 January 2013 (UTC)
    All done. Publishers are added where possible. Anything else? King Jakob C 23:53, 31 January 2013 (UTC)
  3. It is broad in its coverage.
    a (major aspects): b (focused):
    The only concern I have here is the organization of information, as it doesn't seem to flow that easily from one element's information to another's.
  4. It follows the neutral point of view policy.
    Fair representation without bias:
  5. It is stable.
    No edit wars, etc.:
  6. It is illustrated by images and other media, where possible and appropriate.
    a (images are tagged and non-free content have fair use rationales): b (appropriate use with suitable captions):
    Might want to change "recovered from hydrocarbons" to "recovered from the refinement of petroleum/oil" (choose either petroleum/oil), because sulfur isn't strictly a part of hydrocarbons.
  7. Overall:
    Pass/Fail:
    Placed on hold while these issues are addressed.

I will go though the article in more detail over the weekend. Nergaal (talk) 04:40, 23 January 2013 (UTC)

Went through most of the articles and references. Did I miss anything? Nergaal (talk) 19:05, 1 February 2013 (UTC)
As far as I can tell the references are good. King jakob c 2 (talk) 22:26, 3 February 2013 (UTC)

Did it pass?King jakob c 2 (talk) 12:49, 2 February 2013 (UTC)

Sorry for the delay (I was quite busy in the past few days).
I still would like the prose to flow better (but if you can give a reason why not, I'd be convinced). I also think a citation is needed for Frasch's discovery of the original process.--Jasper Deng (talk) 04:55, 5 February 2013 (UTC)
I did another copyedit. As for the citation of Frasch's process, I put the citation at the end of the paragraph.King Jakob C2 01:24, 6 February 2013 (UTC)
"However, Carl..." is followed by another "However," sentence - I think that's a bit awkward. The lead also does not fully summarize the article (does not mention applications, for instance).--Jasper Deng (talk) 06:03, 8 February 2013 (UTC)
Fixed the "however" sentence. And all of the sections with level-2 headings have something about then mentioned in the lead section.King Jakob C2 12:53, 8 February 2013 (UTC)
"Livermorium has not been produced in high enough amounts for its role in organisms to be detectable." - a rather jumbled sentence, and likely wrong, as the polonium article and the info on its toxicity clearly contradict it.--Jasper Deng (talk) 19:03, 9 February 2013 (UTC)
I removed that sentence.King Jakob C2 19:11, 9 February 2013 (UTC)
Actually I mistakenly thought it was dealing w/ Po, but in any case it's a rather jumbled sentence, so if this info is staying it should be written better.--Jasper Deng (talk) 19:26, 9 February 2013 (UTC)
I put the sentence back in, this time just saying that livermorium's toxicity was unknown. Anyway, has it passed now or is there anything else?King Jakob C2 02:16, 10 February 2013 (UTC)

──────────────────────────────────────────────────────────────────────────────────────────────────── Hhm... I'm still a bit skeptical of why we're including livermorium in this because its properties haven't been verified.--Jasper Deng (talk) 23:20, 10 February 2013 (UTC)

The sentence regarding livermorium is gone.King Jakob C2 00:00, 11 February 2013 (UTC)
I mean, how do we know that livermorium is a chalcogen for sure?--Jasper Deng (talk) 04:25, 11 February 2013 (UTC)
I assumed that it was to be regarded as a chalcogen as it is mentioned in the template {{Periodic Table (chalcogens)}}King Jakob C2 12:36, 11 February 2013 (UTC)
Well, as is the case for the carbon family's article, we can't say it for sure - we have to say "possibly".--Jasper Deng (talk) 03:47, 12 February 2013 (UTC)
I did say possibly; should the article even mention livermorium elsewhere in the article, as its chalcogen status is uncertain?King Jakob C2 12:27, 12 February 2013 (UTC)
On that, it may be good to mention relativistic effects on why livermorium may or may not be a member.Jasper Deng (talk) 23:12, 12 February 2013 (UTC)
Actually, I just noticed that John Emsley's book Nature's Building Blocks states that livermorium is a member of group 16 (i.e., the chalcogens).King Jakob C2 23:34, 12 February 2013 (UTC)
But barring chemical experiments we can never be sure.--Jasper Deng (talk) 00:43, 13 February 2013 (UTC)
I wrote in the article that livermorium is predicted to be a chalcogen.King Jakob C2 02:17, 13 February 2013 (UTC)

What is being in group 16? What is being a chalcogen?

The shape of the modern periodic table forces Lv to occupy the space below Po. That much is clear. It is in the vertical column marked 16 even if it does not behave chemically like its lighter congeners (look at Fl). But is that enough for being in group 16? Is a group merely a vertical column in the periodic table? That seems to be not strong enough a definition. Or is it something more? But then, consider element 118. As a gas, it is almost certainly very ignoble. Does that bar it from being titled a "noble gas"? If trivial names and IUPAC numbering names are synonymous, does that also bar it from being a group 18 element? But does that make any sense? And what about the old CAS and old IUPAC names? And does referring to a group as a family show any change in meaning or connotation?

An even stronger question: what is a chalcogen? Must a chalcogen follow its group's trivial name, combining with metals in ores? But then, polonium does not do that, and no one seriously questions its status as a chalcogen. But then does it really mean anything stronger than "group 16 element"? And just what does that term mean anyway?

Is that all "group 16" and "chalcogen" mean, being forced by the layout of the periodic table to occupy a space in the column beginning with oxygen and sulfur? But then, why should "halogen" then mean any more, excluding element 117 (and sometimes even astatine, by some authors)? Why is it then treated as connoting more than "chalcogen"? Is it just that the stable members of that family show greater homogenity? But isn't that inconsistent? But is it used that way? And if it is, don't we need some explanation?

TL;DR: This is a confusing issue! What do those IUPAC numbers and trivial names actually mean and imply? Double sharp (talk) 13:28, 13 February 2013 (UTC)

Regarding the question about what is a chalcogen, this, this and this all indicate that chalcogens are in fact just the column on the periodic table, which would mean that livermorium is one of them.
As for the question about halogens, one could reasonably consider that the halogens as either a group with similar chemical properties (like metalloids), or a column in the periodic table.King Jakob C2 17:01, 13 February 2013 (UTC)
Your first link states that O, S, Se, Te, and Po [Lv excluded, maybe they haven't updated it yet?] are the chalcogens and that they form group VIa (IUPAC: 16). Does that mean anything different from them being in group 16?
Your second and third links seem (to me, at least) to support your statement that "chalcogen" and "group 16" are synonymous.
But none of these sources consider Lv (not even a brief mention, not even as "element 116"), which is problematic as that is the element in question. Is it a chalcogen by definition by virtue of its position in the periodic table (gained from its atomic number of 116), or is it not? If it is not, is the only way it could be officially accepted as a chalcogen a demonstration of its chemical properties? Double sharp (talk) 12:47, 14 February 2013 (UTC)
P.S. Just to avoid misunderstandings, when I say "group" without qualification I mean the concept referred to at group (periodic table). I'm mentioning this because you compared the halogens to the metalloids. (Do all the halogens have similar chemical properties? The first four certainly do, but At, not so much. 117 should be even worse, although 171 should be like Cl and Br again. As such, can we consider them a group using your implicit definition of a collection of elements with similar chemical properties? They are still a vertical column in the periodic table, and must stay that way for periodicity, but is that all a group means? Is that all its trivial name means?) Double sharp (talk) 12:51, 14 February 2013 (UTC)
The point I was trying to make with the external links is that a group (like the chalcogens) is a column in the periodic table. Group (periodic table) and Template:Periodic table (group names) also seem to agree with this. So, given the current arrangement of the periodic table, livermorium would have to be a chalcogen.King Jakob C2 17:58, 14 February 2013 (UTC)
Of course it is. But is it just that? Or is it something else? Is a group described as a column in the periodic table because the elements in the column have similar chemical properties such that they conform to the definition of a group? Then what happens if we do not know the chemical properties of an element that would otherwise be in the group? I apologize if I am being confusing, but this is an interesting question. Double sharp (talk) 08:47, 16 February 2013 (UTC)
The elements in a column don't have similar chemical properties (that's why groups with similar properties, like the metalloids don't always occupy just one column), so the definition of a group can't have anything to do with that...unless one considers valence electrons; if periodic law holds up, every chalcogen should be missing exactly 2.King Jakob C2 12:59, 16 February 2013 (UTC)
From group (periodic table): "The explanation of the pattern of the table is that the elements in a group have similar physical or chemical characteristic of the outermost electron shells of their atoms (i.e., the same core charge), as most chemical properties are dominated by the orbital location of the outermost electron." Double sharp (talk) 15:55, 16 February 2013 (UTC)

────────────────────────────────────────────────────────────────────────────────────────────────────Which is what I was saying above.King Jakob C2 16:12, 16 February 2013 (UTC)

But it means that if the valence electron configuration is the same (s2p4 for every chalcogen), then the chemical properties should also be similar. And indeed, S, Se, and Te are quite similar chemically, of course going down the nonmetal-to-metal gradation. O is an outlier here and is actually commonly excluded from the chalcogens: Po is so metallic that it doesn't behave like a textbook chalcogen anymore. Double sharp (talk) 07:35, 17 July 2014 (UTC)
  • Given that, I think the article can be Yes check.svg passed now.--Jasper Deng (talk) 01:43, 20 February 2013 (UTC)

Orphaned references in Chalcogen[edit]

I check pages listed in Category:Pages with incorrect ref formatting to try to fix reference errors. One of the things I do is look for content for orphaned references in wikilinked articles. I have found content for some of Chalcogen's orphans, the problem is that I found more than one version. I can't determine which (if any) is correct for this article, so I am asking for a sentient editor to look it over and copy the correct ref content into this article.

Reference named "Nature's Building Blocks":

  • From Halogen: Emsley, John (2011). Nature's Building Blocks. 
  • From Neptunium: John Emsley. Nature's Building Blocks. Page 345-346
  • From Carbon group: Emsley, John (2011), Nature's Building Blocks 

I apologize if any of the above are effectively identical; I am just a simple computer program, so I can't determine whether minor differences are significant or not. AnomieBOT 00:15, 16 February 2013 (UTC)

A-class review[edit]

I'm nominating chalcogen for a-class because I'm pretty sure it meets all the criteria (it's long enough, has reliable sources, and doesn't look like it was written by a 2-year-old). King Jakob C2 15:12, 13 May 2013 (UTC)

Based on a first read, my comments fall under three headings: fine-tuning, grammar, and structure.
Fine-tuning
  • When Berzelius suggested the name 'amphigens' what did he have in mind? That is, what does amphigens mean and what was its relevance? And why didn't it get up?

yellow tickY Partly fixed. I found information on the meaning of "amphigen" but could not find anything about why it fell out of common usage, only when it did. King Jakob C2 23:54, 26 May 2013 (UTC)

  • What are 'amphid salts'? Sandbh (talk) 00:47, 9 June 2013 (UTC)
  • Pretty good. So, what's an 'oxy salt"? Sandbh (talk) 12:00, 9 June 2013 (UTC)
  • Livermorium: say something about (a) its uses: presumably none; and (b) its isotopes

Yes check.svg DoneKing Jakob C2 23:54, 26 May 2013 (UTC)

  • Say something about selenium being regarded as a metalloid in environmental chemistry

Yes check.svg Done 23:27, 7 June 2013 (UTC)

  • When you write, "Little is known about Po properties" that is not so. Quite a bit is known about polonium's properties.

FixedKing Jakob C2 23:54, 26 May 2013 (UTC)

Grammar
I noticed a fair number of grammatical errors such as incomplete sentences and a few spelling mistakes. I suggest you carefully reread your article, paragraph by paragraph, looking for and fixing these. Here are some illustrative examples:
  • Many of these contain sulfur but some, such as Na2B2Se7.[23]

FixedKing Jakob C2 23:54, 26 May 2013 (UTC)

  • Selenoethers are in the form of R2Se or RSeR [what does the R mean?]

FixedKing Jakob C2 23:54, 26 May 2013 (UTC)

  • Compounds in the for of M-E

FixedKing Jakob C2 23:54, 26 May 2013 (UTC)

  • A total of 130,000 phosphorus-sulfur compounds, 6000 phosphorus-selenium compounds, and 350 phosphorus-tellurium compounds.

FixedKing Jakob C2 23:54, 26 May 2013 (UTC)

  • Sweeden

FixedKing Jakob C2 23:54, 26 May 2013 (UTC)

Structure
  • Check to see the lede adequately represents the main body of the article

Yes check.svg Done King Jakob C2 23:27, 7 June 2013 (UTC)

  • This will be harder. Some of the sections of the article, such as 1.3 Chemical, have so much information in them that I couldn't grasp the key points of what was being said. The amount of information is not a problem; the issue is the way the information is structured/flows. This can be addressed but will take a bit of work.
I'm happy to look again at this article when the above items have been addressed. I can also help with the last structure point, as time permits. Sandbh (talk) 04:15, 26 May 2013 (UTC)
I will look for more grammatical errors soon. King Jakob C2 23:54, 26 May 2013 (UTC)

TCO comments[edit]

It is a wonderful topic and I am happy to see it being worked on. There are a few places that the article delights me but also many places needing more substantial work (not just polishing of details).

1. Images: Needs more pretty pictures. They really help an article a lot. Find the best ones in appearance and relevance. The S phase diagram and the Mendeleev table are unreadable and boring. Get some picture for Historical. Etc.

Doing... King Jakob C2 12:45, 2 June 2013 (UTC)

Yes check.svg Done? King Jakob C2 23:27, 7 June 2013 (UTC)

2. Lead: needs work to make more engaging and easy. This is the most important text so really needs to be honed. First couple sentences have a lot of formatting. I wonder if just using a hatnote could be helpful here (have an idea of how to do this...) Also, maybe some different places for the para breaks. Get the citations out of there (put content in body and then summarize in lead). And the detail about atomic radii seems not very lead worthy anyhow.

yellow tickY Partly done; rm old style group numbers; they are secondary, bracketed and already in the infobox (note: this way they disapear from the lead, and stay in the infobox, contrary to proposal next point below). Hatnote: see no need; a hatnote is generally not intended for extra information on this topic. -DePiep (talk) 14:06, 3 June 2013 (UTC)

3. Infobox: I like the pics of elements a lot, but think you could go a lot more minimalist and it would work better. how about ditching the outlining and the legend at the bottom and the names (they are in lead already) and just give me our little clickable Periodic Table along with the element pics? Further, please go to WP: Graphics Lab and have them crop you a new version of oxygen that has more the aspect ratio of the others. I want to be able to see that there is more than one, when I see first screen. Also, that thing is just too phallic.

Commented on this below. In general: I do not see the improvements of these proposals. Also, this infobox style & format is used over all groups of course. -DePiep (talk) 14:08, 3 June 2013 (UTC)

4. Refs: lot of Disappearing Spoon and lab group websites. Not enough Greenwood and Earnshaw. For the first ref, please break it out into page numbers. And turn the bare urls into detailed citations. Britannica is unacceptable.

yellow tickY Partly done I've heard the "Britannica is unacceptable" thing before, how come? King Jakob C2 12:45, 2 June 2013 (UTC)
See WP:TERTIARY. Double sharp (talk) 12:47, 2 June 2013 (UTC)
Linked page only says that some such sources are more reliably than others. King Jakob C2 23:27, 7 June 2013 (UTC)
It's not so much unacceptable as frowned upon or discouraged, and only really not a good idea if you have a primary or secondary source that gives the same information. For this, it is almost certain that there is such a primary or secondary source. Double sharp (talk) 11:38, 6 August 2013 (UTC)

5. Properties: If you graphed or tabulated some of the properties, could support the discussion of trends. Also, not sure the crystal structures are so interesting (no trend really) and maybe belongs in a phase/allotrope or chemical section.

6. Isotopes: Too much of a blur of bluelinked numbers in first para. Put that in a table or just cut the list. Also last sentence about spin doesn't really go with the para on decay methods (nor do I understand what it means). Perhaps cut sentence. Yes check.svg Done King Jakob C2 23:27, 7 June 2013 (UTC) 7. Chemical: Fine to discuss the different views, but most people would call polonium a metal. It has metallic conductivity. If it is ductile that would seal it. Also the picture of water belongs in compounds. Also, when you talk about single bonds of S and O, it really is O-O versus S-S in the reference. not R-S versus R-O for instance.

Most people would not, actually, call polonium a metal, none of the chemistry books I've got my hands on call it a metal. King Jakob C2 23:27, 7 June 2013 (UTC)
I struggle with the notion of polonium as metalloid. The literature is about 50-50 as to whether it is a metal or a metalloid. The only arguments I've been able to find on this question are those in favour of polonium being classified as a metal. Tellingly, in my view, I haven't been able to find any sources arguing in favour of classifying polonium as a metalloid. If you go by the approach of classifying the elements on basis of whether they exhibit a preponderance of metallic or nonmetallic properties (or neither, in which case you have a metalloid) then the weight of evidence, based on the literature, falls on the metal side of the line.
Polonium has some nonmetallic properties. It forms anionic polonides, has easily hydrolysed halides and forms an unstable and volatile liquid hydride PoH2. But gold can form anionic aurides and has a heap of other nonmetallic properties. And easily hydolysed halides are relatively common among the poor metals. And tin, lead and bismuth also form unstable volatile hydrides.
It also has some intermediate properties: a coordination number of 6; an electronegativity of 2; an ionisation energy of 818 kJ; and an intermediate metallicity ratio (noting the latter is a non-relativistic construct).
Polonium has, however, more substantial metallic properties: it conducts electricity like a metal; it has a metallic band structure in both of its known forms [an argument killer, in my view, unless there is an undiscovered more stable semiconducting form]; it's enthalpy of fusion of 13 kJ/mol is close to the average of 14.5 for close-packed metals; it is soluble in acids, thereby forming the rose-coloured Po2+ cation, and displacing hydrogen; many polonium salts are known; and the oxide PoO2 assumes the fluorite structure more typical of ionic compounds/metallic oxides, and is predominately basic in nature.
It looks more like a poor metal than a metalloid. In my experience, the authors of text-books that classify polonium as a metalloid tend not to have done their homework and non-critically accept and reproduce the statements of earier, similary less thorough authors. Sandbh (talk) 12:31, 8 June 2013 (UTC)
Maybe the article should just say that polonium could be either a metal or a metalloid, without taking sides? King Jakob C2 14:41, 8 June 2013 (UTC)
It would be fair to say, 'Polonium is sometimes classified as a metal and at other times as a metalloid. Arguments have been made in favour of the former classification, on the basis of the more substantial metallic properties exhibited by polonium, such as its electrical conductivity and cationic chemistry.' Sandbh (talk) 02:33, 9 June 2013 (UTC)
An afterthought on ductility. Polonium, which has a simple cubic structure, is probably brittle. The simple cubic (SC) lattice has few slip systems and hence low ductility and low fracture resistance. It (SC) is also characterised by extreme elastic anisotropy, again suggesting polycrystalline polonium is likely to be brittle (as is the case with As, Sb and Bi which also have notably anisotropic crystalline structures). Finally, polonium at room temperature is thought to comprise a mixture of the alpha and beta phases. I doubt whether this would do anything for it's ductility. Sandbh (talk) 11:39, 9 June 2013 (UTC)
I see also that beta polonium has a rhombohedral structure. As I understand it, such crystal structures have limited slip systems and are therefore relatively brittle. Sandbh (talk) 00:36, 10 June 2013 (UTC)

8. Compounds: Phosphorous at end seems overly long versus the hydrides shortness.

9. Chalcophile: seems like this could go into one of the other sections, maybe occurrence? Don't like the list of blue linked symbols. Instead draw me a little picture of the PT (or part of it) and color in the ones that are chalcophiles. Also the list says chalco in addition (and then has Se, Te, and Po in the list). Fixed

10: Allotropes: Move this so it is before chemistry and compounds. Also, it is too listy (who cares about some of nthe strange allotropes or even theoretical ones). Maybe instead draw me a graph with a temp scale and then show when each element changes phases. Fixed - I don't think the discussed allotropes are theoretical. King Jakob C2 12:45, 2 June 2013 (UTC)

11. Early discoveries: Give me a picture of Greek Flame or one of the scientists or some special experiment. FixedKing Jakob C2 12:45, 2 June 2013 (UTC)

12. Occurrence: that's a great pic, but maybe move to the phases (allotropes) section. Instead if we had one of these centered L-R tables showing the source mineral (or apparatus to produce element) for each one, could be interesting. yellow tickY Partly done

13. Production: less geographic detail and bluelinking in the figure caption please. yellow tickY Partly done King Jakob C2 23:27, 7 June 2013 (UTC) 14. Applications: delete first para. Give me pictures. Fixed - but 1st paragraph moved to bottom of section instead

15. Bio role: Needs picture. Cut the toxicity discussion of polonium. First 5 words of para are all you need. Tox is next section. Fixed

16. Tox: Need picture Fixed King Jakob C2 23:27, 7 June 2013 (UTC) TCO (talk) 07:35, 2 June 2013 (UTC)

re Images. Indeed the top Oxygen picture better be more square, but cropping this picture would leave a cutout. So maybe there is a different picture. In the Mendeleev scheme, shall we mark this group, say a soft yellow background?
re Infobox: Removing the (group) names: ... or remove most of them from the lead? The CAS and old IUPAC name are secondary I think; they cause extra punctuation, and disrupt the reading flow: good candidates to be moved to the infobox (out of the lead). Maybe the pronounciation can go there too. Reducing layout: of course if the markings go (border, atomic number color) the legend goes too. If not, the legend should stay (no unexplained color). All this pertains to all group infoboxes, of course, so any changes should be discussed and applied after zooming out, overlooking all group articles 1–18, where GAs and FAs can be a leading guide. Even better: we should zoom out even more, overviewing all element pages, since we want consistency. Disclosure: I've spend some time on the infoboxes and legends, and my view on information is more tabular than verbose. -DePiep (talk) 09:03, 2 June 2013 (UTC)

The term Chalcogen often refers to the heavier members of group 16, S, Se, Te excluding oxygen.[edit]

Many well known chemists would say the term chalcogen excludes oxygen, e.g Greenwood &Earnshaw in Chemistry of the elements , the excellent series Handbook of Chalcogen Chemistry:New Perspectives in Sulfur, Selenium and Tellurium ed by Francesco Devillanova and Woolf-Walther Du Mont. Shouldn't there be a note that the chalcogen name is not recognised everywhere as referring to the whole group but has been used by many to refer to sulfur and heavier members?Axiosaurus (talk) 10:33, 14 September 2013 (UTC)

P.S this why the term chalcophile mentioned in the article excludes oxygen because oxygen wasn't termed a chalcogenAxiosaurus (talk) 10:37, 14 September 2013 (UTC)
I think I gave King jakob c a comment along these lines some time earlier, that chemists wouldn't group S with O, instead grouping S with Se and Te (and I guess Po if they can afford it?!) I note that pretty much the same applies to the pnictogens (N vs P/As/Sb/Bi). Double sharp (talk) 14:40, 15 September 2013 (UTC)
...and Yes check.svg Done Double sharp (talk) 14:42, 15 September 2013 (UTC)

P.S. Officially, though (per IUPAC), "chalcogen" means the entire group 16 (including O; not sure about Lv). It makes me wonder how much of this is an artifact of O being discussed separately from the true chalcogens (S/Se/Te. Po is marginal; though it could reasonably be said to continue the trend down, I think by then we're at the point that it's more reflective of its true nature to call it a metal rather than a chalcogen), due to its wildly different chemistry, and the term "chalcogen" never actually being defined precisely? (Same for "pnictogen", of course.) And if the chemical differences between O and the true chalcogens mean that sometimes O actually is intentionally excluded from the chalcogens, does Po (and Lv, predicted) ever get similar treatment? Double sharp (talk) 15:38, 17 November 2013 (UTC)

Possible improvements[edit]

A lot of good stuff in this article but I think there are ways it could be improved.

Atomic and Physical section It says paraphrased "All have the same number of valence electron electrons resulting in similar trends." There are other factors. The problem with the chalcogens is that trends are difficult to discern as the group splits into

  • O, highly electronegative, readily forms double bonds, gives best examples of hydrogen bonding.
  • S Se and Te where S and Se are similar but Te does have differences.
  • Po, well that forms Po2+ , completely out of step, and the chemistry is not well known- who would want to work with it and who would fund it?

The elements table could be enhanced to make the O2, S8, Se chain, Te chain, Po metal distinctions more obvious. Also insulator, semiconductor metal distinction.

Needs more on coordination numbers, and possibly redox potentials to add a bit of chemical cred.

Allotropes Se has at least 8 allotropes according to Greenwood. Grey selenium is a photoconductor and used in old Xerox machines - probably worthy of a "for interest" statement. Also a better description is helical chains, quoting the crystal form isn't helpful its the way the atoms attach that tells the chemical story. Te is also helical chains and similar to grey Se.

Describing the crystal form of the solid elements seems irrelevant, the real story surely is that oxygen is O2, sulfur S8, Se and Te form helical chains and Po is metallic. Crystal form is not that helpful.

Chemical section To attempt to write such a summary would intimidate a seasoned academic! Mixing oxygen in with the rest really makes it much more difficult. There is a lot of detail here and either a lot more needs to be added using general text books or it all needs to be scaled back. Comments on what is there now follow.

General point- the discusion of oxidation states is repeated - seems unnecessary. Where is the mention of hydrogen bonding? Key difference.

Polarizability of O2- - wouldn't it be be more accessible to say oxide more ionic than sulfides, selenides etc? Polarizabilty implies an appreciation of Fajans rules. Also I think it's better to use a general text book reference than a thesis on such a general point.

"The oxidation number of the most common chalcogen compounds is -2". If what is meant is that most oxygen compounds are -2 then OK, but it implies the other members of the group too. In these -2 is restricted to simple binary compounds with metals and the hydrides.

"One difference is that sulfur double bonds are far weaker than oxygen double bonds, but sulfur single bonds are stronger than oxygen single bonds." What is being referred to is the relative strength of S-S and O-O bonds, not general single or double bonds to O and S. Also perhaps a better reference.

Tellurate- discrete TeO42- (unlike sulfate and selenate) is actually rare- usually meta-telluates are polymeric anions- an example of Te favouring 6 coordination in contrast to sulfur and selenium in the sulfates and selenates.

Compounds with hydrogen Conspicuous by its absence. Its mentioned in others but that doesn't do it justice. Gives a chance to talk about hydrogen bonding in water and the differences between water and the corresponding S, Se, Te compounds. Also disulfane and polysulfanes and the differences between sulfur and tellurium in forming chains.

Halides Note that semantically oxygen forms a fluoride but the rest are oxides so perhaps "with halogens " would be better.. The statement "The majority of simple chalcogen halides are well-known and widely used as chemical reagents" doesn't compute. Halogen oxides are often really nasty- and are not that widely used. I think the statement may apply to sulfur. "Out of the compounds consisting purely of chalcogens and halogens, there are a total of 13 chalcogen fluorides, nine chalcogen chlorides, eight chalcogen bromides, and six chalcogen iodides that are known", needs a reference. Wikipedia quotes 10 chlorine oxides- so it may not stack up. "These include SeSX, with X being chlorine or bromine. Such compounds can form in mixtures of sulfur dichloride and selenium halides. These compounds have been fairly recently structurally characterized, as of 2008." Firstly the generic formula of SeSX cannot be right reference needed- was it in Devillanova? To be honest not that notable in the bigger scheme. The tellurium lower halides needs references. And what about tritellurium dichloride?

"Halogens and chalcogens can also form halochalcogenate anions" Phrases like this make it sound like they are new and/or unusual. There are some really well known compounds such as chlorates.

With metals There is a massive chemistry of solid state oxides, sulfides etc. These are very important compounds. Any general chemistry text book would be a good starter. There are a lot of interest points points - such as superconductivity, catalysis etc.

With pnictogens Where is the mention of any nitrogen compounds? For example disulfur dinitride, polythiazyl etc.

"A total of 130,000 phosphorus-sulfur compounds, 6000 phosphorus-selenium compounds, and 350 phosphorus-tellurium compounds have been discovered." 130,000 binary phophorus sulfur compounds is this what is meant? Needs a bit of qualification and a reference.

"Almost all chalcogen pnictide salts are typically in the form of [PxE4x]3-, where E is a chalcogen." You can't use P for pnictide! These are salts containg Pnictide and chalcogen anions not salts of chalcogen pnictides as that sounds like a binary compound. Needs a reference.

"Tertiary phosphines can react with chalcogens to form compounds in the form of R3PE, where E is a chalcogen." needs a reference.

Other The interchalcogens deserve a little more detail. The whole paragraph on boron chalcogen compounds doesn't make sense to me, after a brief read of Devillanova it looks like it has been over abbreviated.


Axiosaurus (talk) 15:56, 16 September 2013 (UTC)

Adding to Project Chemistry[edit]

I have added this to Chemistry in the hope of attracting more editors to improve the chemical section. I have not rated it, but the chemical section as it stands is generously B/C borderline. IF it were me I would rewrite the section as a trends only with minimal detail in regards actual chemicals, referring back to the chemical compounds pages. Where they don't exist (like sulfur selenium tellurium and polonium!) they are the pages that need to be written. Axiosaurus (talk) 11:22, 19 September 2013 (UTC)

I could write Po now. The rest I will have to find out more about first. Double sharp (talk) 14:45, 19 September 2013 (UTC)
Perhaps the article could mainly discuss and compare the compounds of the chalcogens with fluorine, hydrogen and sodium? That cld be interesting and illustrative. Sandbh (talk) 21:47, 19 September 2013 (UTC)

Rating a B class[edit]

I have down-graded this chalcogen article to a generous B. I have come back to this article and there have been no fundamental change in it since its elevation to GA status. It is a very ambitious article mixing together oxygen chemistry with the rest of the group- oxygen is so different from the other group members that it invariably warrants separate treatment. (See Compounds of oxygen for the wikipedia take on oxygen chemistry - this rightly failed GA and has been almost ignored by editors ever since.) Simply tinkering around the edges of this flawed article with minor edits is not what is needed, IMO it needs a complete rethink and rewrite. Editors with more chemistry expertise need to be involved. Respected standard texts such as Greenwood and Wiberg should be used to get the scope correct.Axiosaurus (talk) 08:20, 7 August 2014 (UTC)

It did not fail GA. It passed. It's still a GA. You can't just unilaterally downgrade articles from GA. Comments like this are the main reason I quit editing chemistry articles. This elitist culture where experts are the only people who should contribute content gets to me. If you want to rewrite it, do that. Don't just threaten to downgrade articles. If you actually have some ideas, edit this article. --Jakob (talk) 12:09, 7 August 2014 (UTC)
Degrading should follow Wikipedia:Good article reassessment. It also says, an involved editor better not do the degrading individually. I suggest Axiosaurus undo the degrading, and follow the GAR. -DePiep (talk) 13:47, 7 August 2014 (UTC)
A complex wide ranging subject such as the chemistry of a group is as I said before last year on the talk page a difficult task, one to daunt a seasoned academic. I am not one of those. I do however know enough about group 16 to know that this article as it stands is not a good article. The GA process seems to suffer the flaw that the technical content is judged by the stability of the article. However when one or more editors push an article through in short measure, as was done with this article, then this criterion is missed and the review simply focuses on grammar, the presence of references etc. As for Jakec being so upset by their perception of an elitist culture so as to quit editing chemistry articles - well that is regrettable. I shall, when real life allows, get into this Wiki legal process to get this article properly graded. Axiosaurus (talk) 14:55, 7 August 2014 (UTC)
I understand your point, but still. I don't think it will help if we keep letter-warring that status as a replacement for discuss & improve. And this is not the only element-set article that needs this kind of AQ attention (it looks like each and every set needs a dishwash). -DePiep (talk) 15:29, 7 August 2014 (UTC)

Jakec's response to Axiosaurus's comments[edit]

This is really belated, but I think there are a few things that I can fix/clarify/explain.

First of all, the "with pnictogens" section isn't unreferenced. Most of that paragraph is cited to Dillanova, except for the last sentence. (We don't need a reference after every sentence, do we?) I've also clarified the thing about phosphorus-sulfur compounds.

"'Almost all chalcogen pnictide salts are typically in the form of [PxE4x]3-, where E is a chalcogen.' You can't use P for pnictide!"

Why not? Is it because P is also the symbol for phosphorus? I'm pretty sure that this formula is quoted from the Dillanova book, though I can't find it at the moment.

The first paragraph about oxidation states kind of summarizes oxidation states for the whole group and the others go into details. I've put those paragraphs together.

Maybe more will come in the morning. --Jakob (talk) 01:48, 9 August 2014 (UTC)

Hi. Sorry but real life is v. difficult at the moment so i am unable to contribute in this issue in the way that I expected just a few days ago. Firstly glad to see you editing chemistry. Secondly Villanova as a reference is OK BUT it was written as a review of the latest (at the time of writing it) advances in chalogen chemistry. All the pre- 200? stuff has to be found in standard texts. Thirdly yes P is phosphorus and perhaps Vill. did use this, but another non element letter with an explanation would be preferable. The "big issue" with the article is the difference between O and the rest. This is a common theme in the periodic table the 2d period elemnts are always quirky. the chemistry of O and S particlar;y are very extensive and a reasonable coverage would make the article unwiieldy IMO which is why I suggested trends, and then refer to other articles. The only one i could find is compounds of oxygen which has sort of vegetated following a push for status years ago. Dipping out now for a few days.Axiosaurus (talk) 09:52, 9 August 2014 (UTC)
How about "Pn" for pnictogen? Double sharp (talk) 13:27, 9 August 2014 (UTC)

The article does state that oxygen is sometimes separate from the rest of the chalcogens. The discussion of chemical and physical trends also seems to imply that, even if it doesn't explicitly state it. Semi-unrelated: I apologize for being needlessly defensive in the thread above. --Jakob (talk) 01:45, 20 September 2014 (UTC)

Yes, but if you don't explicitly say it every time, it looks like O follows some sort of trend with the rest of the group. Imagine writing an article about group 1, stating in the intro that hydrogen is often separated from the alkali metals, and then putting H together with the alkali metals in every section on the trends! It would spectacularly not fit, but the article wouldn't show that. The article's treatment of O has the same problem, I think. Double sharp (talk) 02:10, 20 September 2014 (UTC)

Problems with this article- flagged as "dubious" and with missing information[edit]

I will add all of the discussion here. These are only the headline issues! (P.S. I flagged the article following the GA reassessment exercise here, where you can see my belated comments relating to the process. I felt it important to put a health warning on parts of the article. Axiosaurus (talk) 12:07, 20 September 2014 (UTC))

With halogens section
oxygen halogen compounds usually the more electronegative element takes the -ide ending.
The numbers of compounds miss out all the oxygen compounds. Probably miss the polonium compounds as well. I don't know where this duff information came from but it may only relate to the chalcogens S, Se and Te.
SF2 is well known, it dimerises and trimerises, also as an aside SCl2 is an industrial chemical used as solven in some vulcaniation processes.
SeSX- presumably this should be SeSX2 with an X-S-Se-X structure- it is in de Villanova!
Solubility of "Chalcogen halides with attached metal atoms " well the solids are often not molecular which is a justifiable inference from the statement. MoS2Cl3 is lattice compound. De villanova says that these compounds are usually soluble in organic solvents.

Axiosaurus (talk) 09:21, 20 September 2014 (UTC)

With metals
Missing information. This is a vast topic containing many significant compounds with very diverse properties. Some obvious misses are the metal oxides which are not mentioned at all. Simple binary chalogenides are not mentioned. The properties are very varied for example oxides may be basic and readily soluble or like a wristwatch sapphire glass inert and hard (its Al2O3). This is not surprising as the whole section is based on a 2008 review of recent advances.
As a general comment- metals here includes groups 1 and 2 and 13 but seems to exclude group 14, 15 metals. The confusion arises because the article treats the chemistry by group except in this case.

Axiosaurus (talk) 09:43, 20 September 2014 (UTC)

With Pnictides
Missing virtually all of the chemistry of nitrogen! and no mention of oxygen compounds with pnictides- probably the most important area containing so many well known compounds. The whole section is based primarily on De Villanovas 2008 review- so as this restricts itself to advances, and the chemistry of S, Se and Te, the article is unsurpisingly very limited in its coverage.
Dubious- the [PnxE4x]3- - this is not the case for the oxides- think of pyrophosphate. Not true for nitrogen - orthonitrate NO43- is a relatively recent discovery but nitrates and nitrites have been known for centuries.

Axiosaurus (talk) 10:15, 20 September 2014 (UTC)

Other
The presence of hydrogen bonding in water and the lack of it in the other hydrogen chalcogenides should be mentioned. Sulfur forms polysulfanes, a simple example of the catenation of S which contrasts with other elements in the group. As an aside nowhere in the article are polysulfide bridges mentioned, these are biologically important and the basis of vulcanization of rubber.
The interchalcogens containing oxygen are a very extensive class of compounds and are given scant attention. This includes all of the oxides and the oxo-acids and the oxochalcogenate salts. Examples are selenium dioxide, sulfuric acid, sulfate, selenate, selenite, tellurate.
The boron chalcogen compunds are not covered, for example the historically well known B2S3 is an example. The impression is given that boron sulfur compounds are hardly known but this is not the case, once again a reliance on the Villanova review is the cause. The example of the borane DMS complex may be incorrect the commercially available form is Me2SBH3.

Axiosaurus (talk) 11:53, 20 September 2014 (UTC)

ME compounds (Group 14 monochalcogenides) firstly SiS is high temperature molecule and unstable, GeS is a well known semiconductor which can be made by reacting GeCl2 with H2S, SnS is actuually a rare mineral. A reference is required for the near meningless staments regarding synthesis and a more balanced/iformed view taken on the relevance of the synthesis.

Axiosaurus (talk) 10:37, 21 September 2014 (UTC)

Allotropes
Greenwood describes more allotropes. these are described in the selenium article. The staement about one of the red allotrpes is at odds with Greenwood where he says that three red monoclinic allotrpes consist of puckered Se8 rings. As an aside α-Po has a unique structure for an element.Axiosaurus (talk) 09:59, 21 September 2014 (UTC)
Chemical
higher oxidation states are progressively less stable as you go down the group, hiwever intersing anomaly with selenium
double bonds stability reduces down the group, and the nature of the double bond changes, heaver chalcogens have debatable d orbital participation
polyatomic cations are a feature of S and Se , different from O
Zintl/cluster ions known
trends in organometallic compounds, chacogenols, so-called heavy ketones etc.etc
coordination chemistry of chalcogen bearing ligands, trends in hard soft acid base categorisation of the elements

Axiosaurus (talk) 15:20, 21 September 2014 (UTC)

Applications
Overall this section has some quite badly written sections. It is over-reliant on one reference- a thesis. Theses are not considered to be properly peer reviewd unlike a journal- it is preferable to quote peer reviewed journals if there is no standard text book available.
through bonds - the reference quoted refers to the electron transfer through bonds as opposed to through space.

Axiosaurus (talk) 17:17, 21 September 2014 (UTC)