Wikipedia:Featured article candidates/Nonmetal/archive7

The following is an archived discussion of a featured article nomination. Please do not modify it. Subsequent comments should be made on the article's talk page or in Wikipedia talk:Featured article candidates. No further edits should be made to this page.

The article was archived by Gog the Mild via FACBot (talk) 22 October 2023 [1].

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Nonmetal

Nominator(s): Sandbh (talk) 12:30, 19 September 2023 (UTC)

While the idea of what a "metal" is has been around since BCE times it was not until over two millenia later that the term "nonmetal" appeared. It was an unfortunate term since explaining what something is not, is difficult.

The structure of the main body of the article has only six sections: Definition—Properties—Types—Prevalence—Uses—History.

There is a table at the end comparing the properties of metals and the different types of nonmetals.

The gist of the nonmetal article should be able to be got by reading only the topic sentence of each paragraph. The technical subject matter means there is some jargon, which I've attempted to minimise.

Since the article was last at FAC, in May-June 2023, it’s been further copy edited, checked for compliance with MOS, the title simplified, the scope honed, and the lede table streamlined. Sandbh (talk) 12:30, 19 September 2023 (UTC)

Comments from Graham Beards

Sorry but I think many of the later additions are not improvements. The prose suffers badly from padding, redundancy, editorializing, and verbosity. Here are examples:

• Within the realm of elemental composition,
• underscoring their pivotal role in the composition of the planet.
• Vital to the composition of living organisms are the nonmetals hydrogen, oxygen, carbon, and nitrogen, which constitute a significant portion of their structural makeup.
• More broadly speaking,
• A degree of ambiguity surrounds
• Further contributing to the evolving landscape of elemental classification
• Approximately half of nonmetallic elements exist in gaseous states, (= are gases)
• with the majority of the remainder being lustrous solids (= most are)
• bromine stands as the singular nonmetal that manifests as a liquid (= the only)
• invariably manifest as solids (= are usually a solid)
• Noteworthy
• Notable
• It is noteworthy
• As to their chemical behavior
• Physically, the unclassified nonmetals appear to lack rhyme or reason.
• In the context of the periodic table
• are recognized as (= are)
• An impressive facet
• A few noteworthy examples
• The majority of (= most)
• Curiously (really?)
• The showcase moment

• "Sodium and potassium, in contrast, exhibited a remarkable behavior—they floated on water." !! Aluminium foil, gold foil, iron ships etc float on water.

Yes, for over two millenia, metals were distinguished from other substances by the fact that (in bulk) they were heavier than water. When Davy, in 1807, isolated sodium and potassium their low densities challenged the conventional wisdom that metals were ponderous substances. Many chemists did not regard them as proper metals. In 1808, Erman and Simon suggested using the term metalloid to refer to the newly discovered elements sodium and potassium. Their suggestion was ignored by the chemical community. The two new elements were eventually admitted into the metal club on the basis of their chemical properties. On the other hand, Davy's discovery "annihilated" the line of demarcation between metals and nonmetals—Hare RA & Bache F 1836, Compendium of the Course of Chemical Instruction in the Medical Department of the University of Pennsylvania, p. 310.

Aluminium was not discovered until 1824, quite a few years later.

I will add have added a footnote about this. Sandbh (talk) 06:09, 24 September 2023 (UTC)

Ref Wiberg 2001, pp. 257–258, 261–262 is a red linked

Fixed. Sandbh (talk) 06:09, 24 September 2023 (UTC)

I still think the "Some cross-type properties" is way too noisy.

After so many FACS, we shouldn't be seeing these issues. Graham Beards (talk) 13:49, 19 September 2023 (UTC)

Thank you Graham Beards.

Re prose, FAC #6 was an austere version without (as you put it) "padding, redundancy, editorializing, and verbosity". I'm happy to revert to the more austere version of prose.

I am sorry that you find the "Some cross-type properties" table at the end of the article to be "way too noisy". It has only five physical properties and five chemistry-based properties. What is it that you find to be way too noisy?

I am sorry that you feel that after so many FACs, we shouldn't be seeing those issues. Before FAC #7 the article had been to peer-review twice and was copy-edited by an editor from the Guild of Copy Editors. Sandbh (talk) 04:47, 20 September 2023 (UTC)

Since then there have been numerous changes. For example:

• "About half of nonmetallic elements are gases; most of the rest are shiny solids." (April 30)
• "Approximately half of nonmetallic elements exist in gaseous states, with the majority of the remainder being lustrous solids." (Current)

Which is not an improvement in my view. Graham Beards (talk) 05:47, 20 September 2023 (UTC)

I agree and will change this to back to the April 30 version. Sandbh (talk) 23:10, 20 September 2023 (UTC)

Graham Beards: I copyedited the whole of the article, offline, to address the prose issues you raised including the examples (which were helpful, thank you). I've posted the revised article. Sandbh (talk) 13:37, 22 September 2023 (UTC)

That's infinitely better and I am close to supporting. There was one fused participle, but I couldn't think of a better wording. How attached are you to the table "Some cross-type properties". I don't think it is needed and it is difficult to understand. Graham Beards (talk) 15:43, 22 September 2023 (UTC)

Thank you Graham. I will take a closer look at the table, see what can be done about it, and report back here. Sandbh (talk) 00:26, 23 September 2023 (UTC)

Graham Beards: That table was not my best work. I have divided the table into two smaller tables and undertook some decluttering and tidying. The introduction to the tables has been rewritten to provide a better explanation and rationale. I feel that this subsection now brings things together in a pleasing way, given its location at the end of the article. Sandbh (talk) 05:52, 24 September 2023 (UTC)

Comments from Mike Turnbull

At present the lead includes the statement In contrast, metals are good conductors and most can easily be flattened into sheets and drawn into wires because of the free movement of their electrons. The part "because of the free movement of their electrons" seems unnecessary, because while it may explain the conductivity I don't think it explains the malleability and ductility and is in any case not needed in the lead of an article about nonmetals. The article ductility is the target for all the terms "flattened into sheets", "drawn into wires" and (in the first main section) "malleability" and "ductility", which suggests that fewer links are needed or some of the text could be removed. Mike Turnbull (talk) 15:51, 24 September 2023 (UTC)

Thank you Mike. I agree the text about free or unfree electrons doesn't need to be included in the lede, and have trimmed it. Per your suggestion I've replaced malleable and ductile with "pliable". Sandbh (talk) 05:13, 25 September 2023 (UTC)

Comments from Mirokado

• §Definition and applicable elements:
  • "they lack most or all the properties..." While "they lack all the properties..." would be correct grammar, here we need "they lack most or all of the properties..." since "most" requires "of".

    I tweaked, see this Google ngram. -- Mirokado (talk) 19:37, 2 October 2023 (UTC)

  • I like the little tables giving quick and prominent access to the articles for each element: I think we should include the wl for Oxygen in the table for a good user interface even though it happens to appear a bit earlier in the section too.
  • "Of the 118 known chemical elements": "chemical" is redundant here, particularly since we have already (correctly) linked to chemical element and then referred to just "elements".
• §Citations: please trigger a run of citation bot. This will probably pick up lots of changes to the citations (adding access icons for example) which would be very fiddly to fix by hand.

More later. -- Mirokado (talk) 19:22, 30 September 2023 (UTC)

Thank you Mirokado.

The first three items have been done. I was expecially impressed by the astuteness of the first one. Sandbh (talk) 05:07, 2 October 2023 (UTC)

Re citation bot check: The citation bot returned the following:

">Remedial work to prepare citations

>Consult APIs to expand templates

>Expand individual templates by API calls

>Remedial work to clean up templates

>No changes required.

# # #

Done with page."

I've nevertheless manually rechecked the first 100 cites, and hope to do the rest relatively soon. Sandbh (talk) 06:28, 2 October 2023 (UTC)

Thanks for checking. When I asked for this, I was thinking about this check of TRAPPIST-1, which resulted in lots of changes even after the article had been promoted. (I have removed some blank lines in the list syntax above, hope that is OK.) -- Mirokado (talk) 19:37, 2 October 2023 (UTC)

Mirokado: I've completed the manual check of all the cites. Sandbh (talk) 00:27, 6 October 2023 (UTC)

• §Allotropes: "Iodine among the halogen nonmetals, as well as the other unclassified nonmetals, and metalloids also have allotropic variations." The comma placement here is problematic and just moving a comma does not work very well either. I suggest rephrasing thus: "Iodine among the halogen nonmetals, as well as the metalloids and other unclassified nonmetals, also have allotropic variations."
• §Secondary periodicity: "groups 16 to 17" would be better written "groups 16 and 17".
• §Types: "Carbon, ... show some metallic character, as does hydrogen." Can we add parentheses or a note to clarify when hydrogen exhibits metallic behaviour ("at high pressure and temperature" for example)?
• §Noble gases: "As a further example, ..." I think this is intended to mean "To add more detail, ...", but since it is the first actual example of a compound in the section, "For example, ..." would be better.
• §Halogen nonmetals: here and elsewhere we are referring consistently to "halogen nonmetals". I have never encountered this nomenclature and think that "halogens" is the common term and cannot be confused with anything else. This contrasts with "alkali metals", since "alkali" on its own has other meanings and common usage.

More later. -- Mirokado (talk) 20:49, 2 October 2023 (UTC)

Thank you Mirokado.

• §Allotropes: The allotropes sentence is quite tricky. Taking your cue I've reworded it as follows:

"Allotropes also occur for the other unclassified nonmetals, the metalloids, and iodine among the halogen nonmetals."

I hope that works for you.

• §2ndary periodicity: Has been done.
• §Types: The metallic properties of H are elaborated later on in the Unclassified nonmetals section, paragraph 4. I have added an intra-wiki link to "as does hydrogen" if that will do.
• §Noble gases: I have changed, "As a further example" to "As a further analogy".
• §Halogen nonmetals: While F, Cl, Br, I and At are halogens, the first four are nonmetals whereas At is expected to be a metal. Ts, which is the heavier congener of At is also expected to be a metal. So I've referred to F, Cl, Br and I as the halogen nonmetals, as per the cited examples. --- Sandbh (talk) 11:10, 3 October 2023 (UTC)

Thanks. I may say more about hydrogen when I look at §Unclassified nonmetals in detail. My familiarity with "halogens" predates serious consideration of At and Ts. Looking again, the usage here seems OK and is reasonably clear from the first image and §Definition and applicable elements. -- Mirokado (talk) 15:38, 3 October 2023 (UTC)

• §Halogen nonmetals: wl first occurrence of semiconductor
• §Metalloids: since the block quote is not itself enclosed in double quotes, we can use double quotes for the quoted quotation marks which are now top-level.
• §Unclassified nonmetals: "It accomplishes this by forming a covalent or ionic bonds": Another tricky phrase, we need "forming a covalent or ionic bond" for good grammar and consistency with the univalent nature of the bonding.

More later. -- Mirokado (talk) 15:38, 3 October 2023 (UTC)

Thank you Mirokado. Those three have been done. Sandbh (talk) 00:27, 6 October 2023 (UTC)

• §Unclassified nonmetals:

  I don't think the three examples of hydrogen behaving like a metal are very convincing. Being metallic is a bulk property deriving mainly from delocalised electrons and no band gap:

  Losing an electron to form compounds is something that metals do too, it doesn't really make hydrogen metallic

  Substituting for a alkali metal atom is a bit more convincing: how does that differ from the "forming a hydride" point?

  Some at least of the hydrides are much more like solutions in that the hydrogen can be readily extracted again (not for example possible with a gold ring ruined by mercury).

  In any case, hydrogen has no ability to exhibit bulk metallic properties on its own under normal conditions.

  Where hydrogen itself is thought to exhibit metallic properties is deep inside gas giants like Jupiter. That is what I was expecting when I first saw the mention of hydrogen as a metal. A suitable reference for this may be the following from Jupiter (DOI link):

  {{cite journal |last=Smoluchowski |first=R. |year=1971 |title=Metallic interiors and magnetic fields of Jupiter and Saturn |journal=The Astrophysical Journal |volume=166 |page=435 |doi=10.1086/150971  |bibcode=1971ApJ...166..435S |doi-access=free}}

  • It is quite proper to retain the current content despite the above when it is supported by reliable sources, but adding the mention of the high-pressure metallic phase would balance and clarify the paragraph. -- Mirokado (talk) 21:21, 6 October 2023 (UTC)
    • @Mirokado: Every element is expected to metallise if you put it under high enough pressure (and low enough temperature). Hydrogen is only special insofar that it requires a particularly high pressure for that: chlorine and xenon metallise at lower pressure than hydrogen. So really, that seems to me to be not very impressive.
    • I'm with you on the idea that metallicity should really be about not having a band gap in bulk, but unfortunately, many authors use it for other aspects of chemistry, such as readily losing electrons. As was already pointed out by R. Thomas Myers (1979), there is no other consistent way to define a metal than looking at high electrical conductivity in all three dimensions; but I suppose if one insists on looking at chemical properties for this, then H⁺ (aq) and the amphoteric oxide H₂O is really what's impressive, as is the ability of H to displace metals from their salts. (Though it raises uncomfortable questions about some of the early 4d and 5d metals.) Double sharp (talk) 04:32, 8 October 2023 (UTC)
• §Extraction: I suggest, add the molecular origin of sulphur from natural gas for consistency with other mentions. I presume hydrogen sulphide?
• §Uses:
  • what is the "endemicity" of a use? Do you mean something like "Widespread uses of nonmetals include:"?
  • one of the most widespread and obvious uses was (and maybe still is) neon in neon lights: does that deserve a mention? I realise it is not possible to mention everything!
• §Discovery:
  • Well done for not wanting to repeat "discovered", but perhaps we can improve "uncovered": how about "Radon is the most recently described nonmetal"?
  • "The noble gases, renowned for their low reactivity, were first identified through unusual and mundane methods." Hmm. What sort of method is neither unusual nor mundane? I see that normal chemistry was not productive, but we really need to rephrase the sentence to say that, or whatever is meant. Even "through both unusual and mundane" does not exclude normal chemistry.
  • "some chemists tragically lost their lives in their pursuit of isolating fluorine." Arrr. I think we can lose "tragically" here  it is a bit like the description of the sinking of the Titanic as "very unfortunate" which I recently reverted.
  • "Antimony, in an unusual twist, was found..." Sorry to be picky, but this is also unencyclopedic: please just say "Antimony was found...". -- Mirokado (talk) 22:11, 6 October 2023 (UTC)

Thanks Mirokado, I much appreciate your careful scrutiny.

• §Unclassified nonmetals: Mirokado, concerning the metal-like properties of hydrogen I've adjusted the article text in an attempt to make this clearer. Please see my longer response to your specific concerns on the talk page for this nomination. --- Sandbh (talk) 06:18, 9 October 2023 (UTC)

• §Extraction: Yes, that's done and I’ve clarified that the listed methods are "mainly or exclusively".

• §Uses:

• In retrospect, "endemicity" doesn't add anything to the sentence so I've trimmed it.

• Neon: Its use in neon lights is subsumed under "Lighting".

• §Discovery:

• Radon: Changed "uncovered" to "identified".

• Noble gases: That sentence now reads, "The noble gases, renowned for their low reactivity, were first identified via spectroscopy, air fractionation, and radioactive decay studies."

• Fluorine: I’ve added a citation for the use of the word "tragically" to refer to the deaths of those folks involved in the pursuit of fluorine.

• Antimony: Thanks, that part now says, "Antimony was obtained primarily through the heating of its sulfidrode, stibnite; it was later discovered in native form.^[210]"

--- Sandbh (talk) 06:11, 7 October 2023 (UTC)

Many thanks to you and user:Double sharp for the detailed discussion about hydrogen. The article text is now much clearer and I take the point about the scope being "in normal conditions". All the above now stricken. I'm away for a few days, so I will continue the review when I get back. -- Mirokado (talk) 21:55, 09 October 2023 (UTC)

• §Origin and use of the term. "In 1875, Kemshead observed..." Who was Kemshead? (Does not seem to have an article). We need something as already done for de L'Aunay: "the French physician Loys de L'Aunay discussed..." Later I see quite a few other unexplained names: generally it is good to indicate in the content why we are highlighting a particular person's contribution, but I see that it may be unwieldy in this case. Please consider and respond.
• §Suggested distinguishing criteria:
  • "The table provided here outlines 22 such properties, listed by type and the year of their mention." I suggest "sorted" rather than "listed" since the table does not include the actual years (I am not suggesting that it should).
  • It is confusing to state the typical case as "metals exhibit an increase... as temperature decreases" but then to discuss the behaviour of exceptions when they are heated. It would be clearer to relate everything to behaviour when something is heated, since temperature is the variable which can be controlled.
  • "when heated within a specific temperature range of −175 to +125 °C." The numbers are already specific: saying "specific" here is redundant. Something like "when heated within the temperature range of −175 to +125 °C." or (shorter) "when heated between −175 and +125 °C."
  • "Nonmetallic elements are predominantly located in the top left quadrant of this table": The nonmetals are in the top right quadrant.
• §Physical: "Form and heft" in the table: heft is not a very familiar word, can we be clearer here? Do we mean "density"?
• §Notes:
  • Note 4: Is "volatizes" really a word? I am familiar with "sublimes" for a solid to gas transition as here, and "evaporates" for liquid to gas.
  • Note 5: I would write "both metals".
  • Note 9: "arsenic, and iodine;" since they end the first list.
  • Note 12: "The single dagger nonmetals N, S and iodine are somewhat hobbled as "strong" nonmetals." I'm not sure what this is saying.
  • Note 37: Please say "Metalloids" rather than "They" here, so the note makes sense on its own (as in other notes). Similarly for notes 39 and 41: strongly what?
  • Also please provide brief context for the lists in notes 42 and 43.

I found some time... I have now read through the whole article so this is "probably" the end of my review. -- Mirokado (talk) 00:07, 12 October 2023 (UTC)

Thank you Mirokado.

• §Origin and use of the term: Re Kemshead; Kneen and colleagues; Emsley; Jones; Johnson; Hein and Arena; and Oderberg I've now repositioned the citations so that they appear next to the name of the author, rather than later on. It's then possible to straightway check the applicable source. Of these authors, only Emsley has a Wikipdeia article to which I've now added a link.
  • "The table provided here outlines 22 such properties, listed by type and the year: Changed "listed" to "sorted".
  • "...metals exhibit an increase... as temperature decreases": I see what you mean and have copyedited the paragraph so that it now consistently refers to the effect of heating on conductivity.
• "Nonmetallic elements...top left quadrant": Fixed, thanks.
• §Physical: "Form and heft": Changed "heft" to "density".
• §Notes:
  • Note 4: Is "volatizes" really a word(?): Changed to "sublimes".
  • Note 5: I would write "both metals": Done.
  • Note 9: "arsenic, and iodine;" since they end the first list: Done.
  • Note 12: "The single dagger nonmetals N, S and iodine are somewhat hobbled as "strong" nonmetals." I'm not sure what this is saying: I've changed this to say, "The single dagger nonmetals N, S and iodine are somewhat hobbled as to the strength of their nonmetallic character:" This is then followed by three bullet points, one for each of N, S and I, discussing their shortcomings.
  • Note 37: Please say "Metalloids" rather than "They" here, so the note makes sense on its own (as in other notes). Similarly for notes 39 and 41: strongly what(?): Done.
  • Also please provide brief context for the lists in notes 42 and 43: Done.

--- Sandbh (talk) 06:02, 12 October 2023 (UTC)

Mirokado: I believe I've now addressed your final comments. Sandbh (talk) 07:24, 12 October 2023 (UTC)

Thank you Sandbh for the prompt responses. The article is greatly improved from the previous version I reviewed. There are good explanations for the reasons for the differences being described.

Support. -- Mirokado (talk) 20:14, 12 October 2023 (UTC)

Thank you Mirokado for your careful assessment and many good suggestions. --- Sandbh (talk) 05:45, 13 October 2023 (UTC)

• §Bibliography: there are several bare urls (search for http in the display), these should be, for example, links in the citation title. -- Mirokado (talk) 21:02, 13 October 2023 (UTC)

Mirokado: Thank you. I've relocated those URLs. --- Sandbh (talk) 23:30, 13 October 2023 (UTC)

Thank you. While checking that, I noticed:

• §Bibliography
  • The book example in the leading comment defining citation style lacks the specified italics for the book name.
  • "Books are in title face italics." While you are changing here, please say "Book names are in title face italics.": clearer and losing the extra space.
  • There are citations missing either quotes or italics for the name (title): for example Angelo and Bache1832.
  • It would be better html style to enclose the whole of each citation in the <span id=..>..</span> container. That would be an easy global exchange (which I would be happy to do if you ask) so please don't make that change for each citation manually.
  • Even further down the rabbit hole, some citation ids such as Bache1832 include the date even when there is only one citation with that first author, others do not.
    • Particularly since you specify a detailed citation style in the leading comment, the ids should follow a consistent schema. The example in the comment does not currently include a date, the comment should say how to handle clashes. Currently, different authors with the same last name are distinguished by adding the initials to the ID (e.g. Cox), different citations by the same author by adding the date. This is fine and sensible.
    • In the case of Edwards, there are three citations with different dates, but one of the ids does not contain the date. Please fix this and any similar case whatever you decide to do (or not) in general. -- Mirokado (talk) 14:53, 14 October 2023 (UTC)

Mirokado: OK. I believe those items are all done now. Sandbh (talk) 05:48, 16 October 2023 (UTC)

Thank you. Once those issues were corrected, it was easy to check the placement of quotes in linked citation titles, I fixed a few inconsistencies.

This series of comments constituted a citation consistency check, for which the result is Pass. ---- Mirokado (talk) 19:14, 16 October 2023 (UTC)

Comments from JJE

There are a few paragraphs lacking citations at the end. I also don't see how a section on nonmetal prices can stay stable and up-to-date enough to satisfy the stability requirements. Jo-Jo Eumerus (talk) 08:07, 1 October 2023 (UTC)

The inclusion of prices contravenes our policy. See WP:NOTPRICE. Graham Beards (talk) 08:39, 1 October 2023 (UTC)

Thank you Jo-Jo Eumerus and Graham Beards.

1. Paragraphs without citations at the end

Jo-Jo Eumerus: I've added citations to most of these paragraphs. The following don't have citations as they are either lede style, summary or explanatory paragraphs:

• "Adding complexity to the chemistry of the nonmetals are the..."
• "After classifying the nonmetallic elements..."
• "Although a distinction had existed..."
• "The dashed lines around the columns for metalloids..."

--- Sandbh (talk) 01:33, 3 October 2023 (UTC)

2. Nonmetal prices

I intend to update these once a year.

In the article, after subsections on Abundance and Extraction, and in light of the many uses of nonmetals, it seemed natural to give an idea of their costs in comparision to silver and gold.

With one exception, the prices were obtained from reliable sources, the premier example of which is the annual United States Geological Survey. The other sources are from the academic literature (×13), Boise State University (×2); and the National Institute of Standards and Technology. Three examples from the academic literature are: mention of the cost of H from a renewable energy perspective; the cost of N mentioned in an economic analysis of synthetic fuel production; and the cost of xenon as an anesthesia alternative.

The one exception is in a footnote at the end of this passage:

"Day to day costs will vary depending on purity, quantity^[n21]...

Footnote 21 says:

"For example, as at April 2023, the commercial price of silicon was $4 per pound or $0.0088 per gram.[192] On the other hand, the price quoted for a 335 gram sample of silicon for hobbyists and science enthusiasts was about $57, or 0.170 per gram, or about 20 times the commercial price.[193]"

• Reference 192 is U.S. Geological Survey 2023, p. 153.
• Reference 193 was Billing Metals & Manufacturing, Silicon, Large Collectors sample. Element 14., accessed May 2, 2023.

The link for R193 is (now) to an Internet Archive snapshot of the web page showing a price of $AU85.

Re WP:NOTPRICE this says in part:

"An article should not include product pricing or availability information (which can vary widely with time and location) unless there is an independent source and encyclopedic significance for the mention, which may be indicated by mainstream media sources or books (not just product reviews) providing commentary on these details instead of just passing mention."

In the context of my explanation I feel there is no contravention of this policy. --- Sandbh (talk) 04:43, 2 October 2023 (UTC)

And where is the commentary here: "Germanium and xenon cost about $1.30 and $7.60 per gram."? This looks like a "passing mention" to me. I think you need to take the numbers out. Although not one of the FA criteria, FAs are expected to be maintained and saying "I intend to update these once a year" is not a valid argument for any of the current content. I am also concerned about the article's stability. Although edits are expected during a FAC in the light of comments from reviewers, there have been scores of edits since this nomination, which reviewers, well at least me, feel obliged to check for FA compliance. This is not what is expected here. Graham Beards (talk) 06:46, 2 October 2023 (UTC)

Thank you Graham Beards.

The commentary for Ge is set out in USGS Mineral Commodity Summaries 2023, which notes that, among other things, Ge is on the U.S. Critical Minerals List.

The commentary for Xe is set out in doi:10.1016/j.bja.2017.10.017. The article includes a mini-economic analysis of the price of Xe, as an anaesthesia alternative, compared to Ar.

Neither of these independent sources appear to constitute passing mentions.

On the nonmetal pricing numbers I have only listed the costs for the five nonmetallic that are more expensive than silver, for contrast and comparison purposes, and to flag their possible economic significance (Rn now excepted). In this context I have refurbished the Uses section so that there is more of a focus on these higher cost nonmetals.

Since the USGS Mineral Commodity Summaries are published once a year, and most of the costs come from that source, this is what informs the proposed yearly update of the costs.

Jo-Jo Eumerus, lead editor for the recently promoted FA article TRAPPIST-1 similarly flagged a yearly update for that article. I mention this as I reviewed the article for promotion suitability.

On the stability of the nonmetal article I am sorry that you feel the number of edits (~173) since the article was nominated were not expected. TRAPPIST-1 underwent 163 corrections between nomination and promotion, and has attracted a further 16 edits since then.

Looking at side-by-side versions of the nonmetal article as at 22 Sep, when I posted the off-line copy-edited version in response to your valuable feedback, and the version as I wrote most of this response (3 Oct), the overall structure of the article did not appear to have changed. What has changed (including as informed by your further feedback) are matters of presentation and detail which I suppose would not be unexpected during an FAC review.

I have appreciated your interest in this nomination given your more thought-provoking comments have resulted in improvements to the article. --- Sandbh (talk) 06:19, 5 October 2023 (UTC)

With regard to "providing commentary on these details instead of just passing mention", the commentary is not summarised in the article. All we have is a passing mention. It is unwise to single out other FACS to support your comments. I have been active here for around 15 years and I could find countless examples of FACs to back up mine. This pricing issue is a deal breaker for me, so I Oppose promotion until we find a solution. Sorry. Graham Beards (talk) 06:44, 5 October 2023 (UTC)

Thank you Graham Beards.

I haven't been active at WP:FAC for as long as you.

Until I just now re-looked closely at the Costs subsection I had not appreciated that commentary about nonmetal pricing is at its start, middle and end:

"Day to day costs will vary depending on purity, quantity,^{[n 22]} market conditions, and supplier surcharges.^[195]" [start]

"Based on the available literature as of April 2023...^[196] [middle]

"Additional factors associated with the higher costs of some nonmetals include relative scarcity (Ge, Xe)^[204] and costly production techniques (B, P, Ge).^{[205][200][204]}" [end]

Sorry for not mentioning that to you in my earlier response.

As required, I could attempt to add some further background about the scarcity and orneriness of the five higher-priced elements. Sandbh (talk) 07:49, 5 October 2023 (UTC)

I would delete the whole section. Graham Beards (talk) 08:18, 5 October 2023 (UTC)

Graham Beards: I have done so. The content is now in its own article, Costs of nonmetals which I can work on in slower time. I have added a link to "Costs of nonmetals" in the See also section of the nonmetal article. --- Sandbh (talk) 03:49, 6 October 2023 (UTC)

Sorry, that's not a solution in my view. You have created a sub-article, the content of which is non-compliant with WP policies. Graham Beards (talk) 06:53, 12 October 2023 (UTC)

Graham Beards: Thank you. Costs of nonmetals has been deleted. The link to Cost of nonmetals in the Nonmetal article has been removed. There is now no cost content in the Nonmetal article. Sandbh (talk) 02:55, 13 October 2023 (UTC)

Coordinator note

A wall of comments, but with no declarations of support or opposition it feels more like a PR than a FAC. There still seems a way to go to achieve any consensus to promote, or even signs of movement towards it. This has been open for three weeks now, and unless there is significant movement towards a consensus to promote over the next three or four days, the nomination is liable to be archived. Gog the Mild (talk) 14:31, 10 October 2023 (UTC)

Gog the Mild: Noting all concerns raised by the FAC commentators seem to have been addressed I suggest at least waiting for Mirokado to complete their assessment. On 9 Oct Mirokado advised that, "I'm away for a few days, so I will continue the review when I get back." When their review has been completed I intend to ask the FAC commentators, along the lines of your set of words, if they feel in a position to either support or oppose the nomination noting that obviously neither is obligatory. --- Sandbh (talk) 00:46, 11 October 2023 (UTC)

That sounds reasonable. I certainly have no desire to close a nomination prematurely. So let us wait a week and see what they say. Gog the Mild (talk) 13:50, 11 October 2023 (UTC)

Eight days on and I see no sign of this moving any closer to a consensus to promote. I am again inclined to archive unless you could provoke some such movement in the next 48 hours. Gog the Mild (talk) 18:09, 19 October 2023 (UTC)

Thank you Gog the Mild. It's Friday mid-morning my time, as I write this. I propose to let you know what the situation is on Monday mid-morning my time. I hope to have a sufficient indication from the reviewers by then as to what the consensus situation does or does not look like. I'll ask you to either keep open or archive the nomination at that time. Thank you for your patience. --- Sandbh (talk) 00:07, 20 October 2023 (UTC)

My 48 hours is now nearly 72 and Graham Beards has recommended archiving. I agree. I am archiving this. I suggest that this gets further work off-FAC, possibly with input from the reviewers here, and bring back a final, definitive version. Gog the Mild (talk) 15:16, 22 October 2023 (UTC)

Polite comments. @Gog the Mild: With respect, once again a nomination of mine has been closed by you before I've had the opportunity to respond to closing comments. I advised you of my intention to let you know what the situation is on Monday mid-morning my time. You thanked me for that advice. It is now that time and I find that the nomination has already been archived. Considerable signs of movement towards consensus to promote has occurred. There is a support from Mirokado; Michael D. Turnbull is inclined to support. YBG was inclined to support. Double sharp was neutral but was inclined to support subject to a few adjustments. Graham Beards was close to supporting. I can't control if reviewers choose to do a line-by-line review as I did with TRAPPIST-1. Please consider reopening the nomination in order to let me complete the last few change requests. Alternatively I'll be back in two weeks. No hard feelings. Thank you for reading. --- Sandbh (talk) 22:48, 22 October 2023 (UTC)

@Graham Beards, Michael D. Turnbull, Jo-Jo Eumerus, Double sharp, and YBG: In light of GtM's comments above could you provide an indication of whether you would be inclined to support or oppose the nomination, subject to me addressing any outstanding comments? There is no obligation, of course. Aside from Mirokado's support, I'm attempting to gauge whether the climate of consenus is postive, mixed, silent or negative. If there are sufficient inclinations then I hope the nomination can continue to stay active; otherwise I'll ask GtM to archive it. Thank you, --- Sandbh (talk) 00:07, 20 October 2023 (UTC)

@Graham Beards, Michael D. Turnbull, Jo-Jo Eumerus, Double sharp, and YBG: Now that Mirokado has completed their assessment, and I believe that all items of concern have been addressed, I was wondering if you felt in a position to either support or oppose this nomination? Obviously, neither is obligatory. --- Sandbh (talk) 23:52, 13 October 2023 (UTC)

Gonna need some input from editors who have an understanding on the "how is the term 'nonmetal' used in chemistry" question. Jo-Jo Eumerus (talk) 12:47, 15 October 2023 (UTC)

It depends on the author in question and what the author thinks are metallic properties. Generally, elements that seem to fail most of the metallic properties being considered by the author are called nonmetals. Some authors add a "metalloid" category where things seem to be roughly in balance. On the other hand, many of the properties that have been offered by sources seem to contradict actual practice. For example, just listing things from the "Suggested distinguishing criteria" section: "Physical state" leads to questions about Hg (plus the fact that many elements often called nonmetals are solid), "Packing efficiency" suggests that the noble gases are excellent metals, "Cation formation" (if it's for aqueous solution) suggests that a bunch of transition metals (including tungsten) are not really metals (and if it doesn't mean in aqueous solution, then it would start including things like iodine), and "Acid-base character of oxides" depends on oxidation state. (No one actually would agree to those conclusions, I think, but they are what you would get by applying those criteria literally.) The most that can be said is that having a metallic or semimetallic band structure tends to be weighted quite highly: this property by itself is a near-guarantee that something will be called a metal rather than a nonmetal/metalloid. Even so, many authors will still demur if enough other metallic properties are failed, as happens for As, Sb, and less often (but still to a significant degree) Po. (If we then go to even rarer rejections, Al, Bi, Be, and Sn have been called metalloids more than 1% of the time.) And orthogonally from all this, you have cases like At and the superheavies where it's impossible to give a final judgement because not enough is known experimentally – though some of these get called metals by universal acclamation (Fr, last few actinides and early 6d elements) because there's really no doubt in people's minds that they would be metals if you could ever test them. Double sharp (talk) 13:01, 16 October 2023 (UTC)

@Double sharp:So is electronegativity and density a criterium? Jo-Jo Eumerus (talk) 09:02, 17 October 2023 (UTC)

@Jo-Jo Eumerus: They are sometimes given as properties that tend to be characteristic of nonmetals, which they are. But they're not a definition that gets everybody: gold has high electronegativity (higher than silicon), lithium has low density (less than water), and neither are ever called nonmetals. Meanwhile nonmetallic germanium is denser than titanium and has about the same electronegativity as polonium, both metals. Double sharp (talk) 11:16, 17 October 2023 (UTC)

Seems like the article has a problem then if it stipulates them as criteria. Jo-Jo Eumerus (talk) 11:26, 17 October 2023 (UTC)

@Double sharp and Jo-Jo Eumerus: Thank you both. Could you please note that the article starts as follows,

"A nonmetal is a chemical element generally characterized by low density and [emphasis added] high electronegativity ..."

While gold has a high electronegativity it has a high density rather than a low density; while lithium has a low density it also has a low rather than high electronegativity. Neither gold nor lithium meet the criterion. Germanium, on the other hand, has a relatively low density and high EN and meets the criterion. Titanium has a low density and a relatively low electronegativity, it being a metal. Polonium has a relatively high electonegativity but a relatively high density, it too being a metal.

I trust this clears up any confusion? Sandbh (talk) 04:15, 18 October 2023 (UTC)

Then I'd ask:

• Is there an RS giving precisely these two criteria as a definition, rather than as two among many tendencies nonmetals have? And if one exists, is doing that as common as the physics idea of what a metal is?
• What then about Sn, with Pauling electronegativity 1.96 (compare Si 1.90), and density 7.265 g/cm³ (compare Sb 6.697)? Yes I know you cite an author who uses 7 g/cm³ as a threshold, but that is as a threshold for whether or not a metal is heavy, not whether or not a chemically weak candidate should have its metallic credentials questioned. (And why are we citing a 1936 textbook?)

Double sharp (talk) 10:48, 18 October 2023 (UTC)

Thank you Double sharp. In my reply following, italicization appearing in quotes from the article has been added by me. And I've used ◇...◇ to distinguish section headings in the article.

As a couple of contextual comments, the article notes in several places that variations occur as to precisely which elements are nonmetals, depending on the author or source. Likewise, in FAC #6 Michael D. Turnbull, an organic chemist, opined that "it is inherently difficult to write an article about a topic that is defined by what it is not: not-a-metal, especially when there are clear edge cases."[2]

• There is no single source that I'm aware of that defines nonmetals precisely in terms of the two criteria. Rather, low density and high EN are two of the many properties mentioned in numerous texts as being characteristic of nonmetals. This is why the lede is worded the way it is namely, "A nonmetal is a chemical element generally characterized by low density and high electronegativity ...". Similarly, the ◇ Definition and applicable elements ◇ section starts, "In general, a nonmetal is a chemical element that can be characterized by low density and high electronegativity."

The qualifiers, "generally", "In general", and "can be" imply that while most nonmetals exhibit these characteristics, there may be exceptions or variations among nonmetallic elements. The remainder of the first paragraph in the lede elaborates:

"They range from colorless gases like hydrogen to shiny solids like the graphite form of carbon. Nonmetals are often poor conductors of heat and electricity, and when solid tend to be brittle or crumbly. In contrast, metals are good conductors and most are pliable. While compounds of metals tend to be basic, those of nonmetals tend to be acidic."

This is why the lede includes the following text:

While the term “non-metallic” can be traced back to at least 1566, there is no universally accepted definition of a nonmetal. As some elements have a marked combination of metallic and nonmetallic properties, lists of nonmetals typically vary from 14 to 24 members.

The ◇ Definition and applicable elements ◇ section further caveats that, "There is no precise definition of a nonmetal;^[4] any list of such is open to debate and revision.^[5]"

Later, in the ◇ Suggested distinguishing criteria ◇ section, there is a comment about the use of single criteria:

Emsley^[264] pointed out the complexity of this task, asserting that no single property alone can unequivocally assign elements to either the metal or nonmetal category.

It is why the penultimate paragraph of the ◇ Suggested distinguishing crieria ◇ section is worded as it is:

Hein and Arena^[65] observed that nonmetals have, among other properties, low densities and high electronegativity, which is consistent with the data presented in the table. Nonmetallic elements are predominantly located in the top right quadrant of this table, where density is low and electronegativity values are relatively high. In contrast, the other three quadrants are primarily occupied by metals.

The predominately and primarily qualifiers are intended to be consistent with authors varying in their treatment of which elements are metals or nonmetals.

• Since nonmetals are typically characterized by physical and chemical properties, that tin has a density of 7.265 g/cm³ is, by itself, neither here nor there (so to speak). That it has an EN of 1.96 is, by itself, neither here nor there. When the two are taken together the result is an element with a relatively high density and a relatively high EN, which suggests it is not a nonmetal. About the figure of 7 gm/cc, I recalled that the FA Heavy metals article mentioned a range of density cut offs: "Density criteria range from above 3.5 g/cm³ to above 7 g/cm³.[3]". The age of a source does not necessarily affect its relevance. I was going to say that I could deprecate mention of the 7 gm/cc figure to a footnote, only to find that I had already done so. I've now added a wlnk to the mention of "heavy metals" so as to place the mentioned figure into context.

Summarising, I'm attempting to package a "wobbly" concept and have strived to ensure there is enough leeway in the article to encompass most views set out in the literature. I'm happy to consider any suggestions for further fine-tuning as to the way the article seeks to encompass its scope.

--- Sandbh (talk) 01:12, 19 October 2023 (UTC)

So you admit that the cut-off of 7 g/cm³ is about whether or not a metal is heavy, and not whether or not a chemically weak metal candidate should be rejected and considered a nonmetal instead. That means that the way you use it is a WP:SYNTH, isn't it?

And you admit that density and EN are not really accepted as distinguishing criteria, and are merely two of the many properties often accepted as characteristic of nonmetals. So isn't it going beyond what's justified by RS to single them out the way you do?

I'm quite familiar with the situation of writing a WP article about something where there is no universally accepted definition. I did save Planet at FA some time ago, you know. :) But what I did there is to start the lede with only the common denominator everyone would agree with, and then mention that there are differing views. (For this article, this would mean saying that nonmetals are generally things that authors think don't have enough metallic properties, and use 3D electrical conductivity as a baseline, mentioning that there are some exceptions.) And I didn't exclude anything that some authors have considered planets, even if in some cases I find the inclusion incredible (Hygiea springs to mind), although naturally I covered only the most common inclusions in the biggest detail. That is also what you did at Metalloid. Why not just do that, instead of appearing to push a definition, and not wanting to talk about things that some RS doubt even though you think they are clearly metals? I'm personally in Steudel's camp and think that Sb is a metal, but that doesn't mean I'd exclude it from a WP article discussion of metalloids or nonmetals, because some serious RS have a different opinion. Same story with beta-Sn and Po, at least. Double sharp (talk) 01:31, 19 October 2023 (UTC)

Thanks Double sharp.

Some of your concerns are addressed in my 00:51, 20 October 2023 response to your philosophical concern/s.

The 7 g/cm³ figure wasn’t chosen by me. It so happened that the chart mapping the elements according to their density and EN happened to fall out that way. It was only after I drew the chart that I remembered the 7 figure.

I've changed the footnote to read:

A survey of definitions of the term "heavy metal" reported density criteria ranging from above 3.5 g/cm³ to above 7 g/cm³.^[276]

I feel this is a neutral statement.

I’ve shied away from 3D-electrical conductivity for the following reasons:

• Single properties don't work as per Emsley, and over two centuries of attempts have shown.
• It requires a caveat in the case of As and Sb.
• Density has a long association with pre-chemistry and chemistry, at first as a way to distinguish metals from other substances. With the isolation in 1807 and 1808 of Na and K (both being lighter than water, which was an astonishing finding in its day) chemists had to further look to chemical behaviour to conclude that Na and K were indeed metals.
• Na and K highlighted that while density was an important property often associated with metals (and it still is in terms of the loose concept of heavy metals), it wasn’t the sole determinant of their behavior i.e. there were such things as lightweight metals that still behaved chemically as electropositive metals.
• Chemistry, rather than physics so much, is the broad focus of the article.
• Electronegativity as a way to characterise the elements dates back to the days of Berzelius, in the 1810s and 1820s, with his notions of electropositive and electronegative behaviour.
• Goldwhite & Spielman (1984, p. 130) related density and EN, when they wrote, "lighter elements tend to be more electronegative than heavier ones".

Summarizing, density and electronegativity have had a significant interrelated relationship and still do.

3D electrical conductivity is nevertheless included in the table of 22 suggested single properties for distinguishing metals from nonmetals (1811–2017).

Like Metalloid, and Planet, I've attempted to broadly describe nonmetallic elements. One of the important things is the nature of their physical and chemical properties, hence the mention of density and electronegativity.

Those two properties are just two of the up to fifty or so properties that RS use in attempts to characterise nonmetals.

In light of your concerns I've changed the opening sentence to:

A nonmetal is a chemical element generally characterized by, among other properties, low density and high electronegativity (the ability of an atom in a molecule to attract electrons to itself).

This seems to be (a) accurate, with wriggle room provided by the "generally"; (b) relatively inclusive; (c) balanced; and (d) congruent with the literature.

The article further mentions a plethora of properties, and I've attempted to go to considered and considerable lengths to mention the general and indicative-only nature of those properties, including density and EN.

I’ve expanded the start of the last paragraph in the Suggested distinguishing criteria subsection to read:

Several authors^[278] have noted that, in general, and among other properties, nonmetals have low densities and high electronegativity, which is consistent with the data presented in the table.

The article mentions Sb and As being sometimes conceived of as metals:

Since metalloids occupy a transition region or "frontier territory",^[122] where metals meet nonmetals, their classification varies among authors. Some consider them distinct from both metals and nonmetals, while others classify them as nonmetals^[123] or as a sub-class of nonmetals.^[124] There are also authors who categorize certain metalloids as metals, such as arsenic and antimony, due to their similarities to heavy metals.^{[125][n 17]} In this context metalloids are here treated as nonmetals, based on their relatively low densities, high electronegativity, and chemical behavior,^[120] and for comparative purposes.^{[n 18]}

--- Sandbh (talk) 11:43, 21 October 2023 (UTC)

Mike Turnbull and Double sharp may be able to help in this regard. Sandbh (talk) 07:21, 16 October 2023 (UTC)

Hrmm. I really don't want to leave this one with no conclusion since it's the 7th FAC of this article, but the issue of the definition is a big issue. If different people (hereby defined as "which meet RS and DUE") use different definitions of "nonmetal" we can't cherry-pick one particular definition and put it in the lead. Rather you'd have to enumerate the various definitions, or say "Nonmetal is a grouping of elements. Different sources use different definitions" or somesuch. Jo-Jo Eumerus (talk) 11:08, 20 October 2023 (UTC)

@Jo-Jo Eumerus "Metal/Nonmetal" is one of a number of ways that chemists divide their subject-matter. "Organic/Inorganic" is another and "Element/Compound" a third. With all these broad-brush divisions, there are differing views about the exact boundaries: for example, many would argue that carbon monoxide is inorganic while some would call it organic because they define "organic" as any compound which contains carbon. Likewise, some chemists would categorise S₈ as a compound while others would just consider it one of the possible allotropes of sulfur. In the context of the current article, I agree with your last comment: the variation in our reliable sources needs to be reflected in the text. For me, the bottom line is that Wikipedia definitely needs an article called nonmetal and the one that we now have does a good job of explaining the complexities of the situation. Hence (as @Sandbh asked) I'm inclined to support promotion to FA status. My only hesitation is because of my lack of experience of assessment at this level. Mike Turnbull (talk) 16:34, 20 October 2023 (UTC)

User:Jo-Jo Eumerus I agree that it is not good to cherry pick definitions. Nevertheless, it is common in WP list articles to define the scope of the list in the lede. Now I know this is not a list, but I think a similar principle should be kept in mind. Which elements are considered in this article? This article takes a broadly inclusive approach, and includes just about any element that any RS calls a nonmetal. I believe the only exception is astatine, and the reason for excluding it is explained in at least two places in the article. Even if At were included, it would add almost nothing to the article: since it is so rare and so radioactive, no one has ever had even a thimbleful of it to be able to experiment on. I’m pretty certain there are no other elements excluded from this article that are called “nonmetals” anywhere except in fringe sources (or astrophysics, as noted in the hatnote). YBG (talk) 02:36, 21 October 2023 (UTC)

Occasionally you can see other elements wondered about, though mostly in old sources when polonium was not so well-known, or when it wasn't clear that beta-tin was a semimetal rather than a semiconductor. Occasionally things get included for comparison, like Gary Wulfsberg sometimes does in his textbook for Sn, Pb, Bi, and Po, or Sherwin and Weston who admit that Po is best classed as a metal but put it in their book on nonmetals anyway on the grounds that its chemistry is conveniently discussed with the other chalcogens. (They don't say it outright for Sb and Bi, but since they call both metals, this is probably their reason for including them too: to keep the pnictogens together. As for Sn and Pb, Sherwin and Weston say they "are not typically metallic in the truly chemical sense"; but they include them in a table only for comparison and admit that "a detailed study of these elements is outside the scope of this book". Strangely enough it also does not talk much about Ge.) I feel like this could use simply a brief mention; it's something like people who include Vesta and Pallas as planets. It happens enough to mention that such ideas exist, but not enough to actually put them in the tables. (I suspect, though haven't checked, that authors who would include Po as a metalloid would generally be in the camp that metalloids should really be things that are intermediate between metals and nonmetals, and so they would not usually be outright saying that Po is a nonmetal by such an inclusion, only that it has some marked nonmetallic properties. That much is uncontroversial.)

I largely agree with YBG. The list of nonmetals is actually fairly widely agreed on, with a few issues for intrinsically borderline elements. The actual issue is that nobody really agrees on the criteria being used. And quite often criteria are stated and then ignored, as can be seen from the list at "Suggested distinguishing criteria": if you actually try to follow many of them to the letter, you'll often end up including some elements that nobody actually thinks are nonmetals. (Rhenium is my favourite go-to example, because it essentially fails all four of the chemical criteria offered for being a metal. But no one doubts that it is one!) Based on this, I would say that philosophically, the things that would most incline me towards promotion is:

• Avoid explicitly singling out one or two criteria in the lede. Instead, say that there's no agreed definition, but that generally the list of elements is agreed on. (I offered some wording below.) Instead, mention a sample of criteria later than the first paragraph, and note the problem that they are not always applied consistently; they are really rather tendencies. (With the possible exception of 3D electrical conductivity, because that is the physicist's definition of what a metal is, though it should be made clear that chemists will not always agree with it, noting As.)
• As for metalloids, I would much prefer it if it was stated that they're included in order to be comprehensive, rather than making a statement in Wiki-voice at the beginning about their density and chemistry. Doing that raises questions that are hard to answer without OR, like "how low is low when literally twenty metals are less dense than tellurium [Li, K, Na, Rb, Ca; Mg, Be, Cs, Fr, Sr; Al, Sc, Ba, Y, Ti; Eu, Ra, Ga, V, La], including amphoteric and chemically weak Be and Al, and tellurium at least passed the bar of forming an hydrolysed aqua cation Te(OH)₃⁺ in water". We can always talk about how metalloids differ from metals and the more standard nonmetals later, as tendencies (which circumvents a lot of the problem with using many things as criteria).
• De-emphasise the pairing of metal and nonmetal classes, for reasons YBG has already talked about.

As of today I'm neutral; changing these things would incline me to support. Double sharp (talk) 03:48, 22 October 2023 (UTC)

Thanks Double sharp.

1. I believe that not singling out one or two criteria in the lede can be achieved, per your suggested set of words.

2. Metalloids should be doable.

3. I've added a citation mentioning all four pairs.

More to follow.

--- Sandbh (talk) 04:12, 22 October 2023 (UTC)

@Double sharp: User:YBG boldly implemented #1. Please check the lede accordingly. I believe metalloids are now OK.

--- Sandbh (talk) 04:22, 22 October 2023 (UTC)

Comments from Double sharp

Well, it is my turn, I guess. :)

Lede

• I'm not really sure low density and high EN are really the most salient properties. Alkali metals have low density, but chemically speaking they are rather the best metals. Gold has a really high EN for a metal, yet physically it's an excellent metal. It seems better to start with the Myers criterion (3D electrical conductivity), because it mostly gets at what people actually call metals vs nonmetals in practice. Yes, As and Sb are exceptions (well, in one allotrope each anyway) if you think they are nonmetals (and if one wants to call Po a metalloid, it may be added as well), but at least then the very few elements that fail to meet the rough-and-ready definition would be borderline in many ways, instead of being great at one property and bad at the other.
• KOH is a strong base; should we count it as a metal or a nonmetal compound? If we consider it a metal compound because of the potassium, then the fact that HMnO₄ is a strong acid becomes awkward to deal with. Acidic vs basic compounds is rather about oxides specifically. And even then it needs qualification based on the oxidation state (consider acidic CrO, amphoteric Cr₂O₃, basic CrO₃).
• It's not clear that nonmetals dominate in the crust. Na, Mg, Al, K, Ca, Ti, Mn, Fe are all more abundant in the crust than N. If you talk about the atmosphere, then yes, but this is kind of trivial because "atmosphere" implies "gaseous" and there aren't too many gaseous metal compounds at standard conditions. In the biosphere, P and S would eclipse Si; and in the atmosphere, Ar clearly eclipses Si.
• Rest seems OK on first reading.

Definition and applicable elements.

• Same complaint re the first sentence, really. And there are too many exceptions for forming basic oxides to really be a good "metallic" property. It is mostly confined to the active metals (high in the reactivity series), and since nobody thinks that noble/refractory metals like Ta, W, Re, Os, Ir should be excluded from being metals, I question if it is a defining property. I agree the issue is complex and authors have different opinions, which is why I think starting with electrical conductivity would be a better option. At least it gets almost everything people think is a nonmetal.
• By saying that you're going to treat metalloids as nonmetals, aren't you kind of giving a POV-ish justification? It would be fine with me if you said that some authors think they are on the grounds that "nonmetal" ought to mean "anything that's not a metal", and you want to be as inclusive as possible. But I would imagine that most authors who talk about "metalloids" do not think that they are clearly closer to one side or the other as you state by talking about their "predominantly nonmetallic chemistry". Otherwise they would probably not be using the intermediate category "metalloid" at all. And BTW, doesn't "predominantly nonmetallic chemistry and weak acidity" equally well describe rhenium?
• The rest (on the ephemera) is fine, we've discussed that already.

General properties, Physical

• First paragraph is fine. I notice from the note that Mn actually has lower conductivity than As; this overlap seems interesting enough to mention. (It rather supports some points about how it is difficult to draw a clear line.)
• It would be nice to give some explanation for why the nonmetals vary so much in internal structure and bonding arrangements. I wrote such a thing at Periodic table#Metallicity. I know you have something in the last paragraph, but even once the metals have been taken apart from the nonmetals, there's still a massive variety in the latter. The reader probably wants to know why antimony and neon are so different.
• In grey As and Sb we do not just have weak metallic interactions between layers, we actually have metallic conductivity in three dimensions. (True, much more anisotropic in As than in Sb.) So really they are not so much examples of physical properties of nonmetals, but rather examples of how elements that are physically metals can end up getting excluded by some authors if they have enough chemical weaknesses. (BTW, by that logic, even Sn (noting the grey allotrope), Bi and Po would be within scope, something like how N, Zn, and Rn are highlighted in one of the tables in metalloid as examples of the net being "cast very widely" at times. See e.g. here for a remark about Sn.)
• Probably worth mentioning that graphite is only really a good conductor in 2D. Its properties and structure are quite anisotropic.
• Because carbon has two very well-known allotropes, I think that for clarity you should explicitly say that you are talking about graphite, rather than just using the hatnote at the top.
• Re the last paragraph, even in metals the electrons are not fully delocalised. Firstly not all metals are close-packed, and secondly not even caesium has a spherical Fermi surface. There is rather a continuum. (Which might help in handling cases like grey As.)

General properties, Allotropes

• Really this should be discussed before physical properties. Physical properties of an element (really, its simple substance) vary significantly between its allotropes (e.g. diamond vs graphite, white vs red phosphorus). Chemical properties are not limited to the simple substance, though.

More later. Double sharp (talk) 12:24, 16 October 2023 (UTC)

Thank you Double sharp for your careful reading of the article.

At the outset, I've relocated the hatnote about << the elements in their most stable forms >> to the top of the article, as I suspect this may address some of your concerns.

Lede

• Nonmetals are usually described in terms of their physical and chemical properties, hence the mention of a physical property (density) and a chemical property (EN). 3D electrical conductivity is mentioned later in the distinguishing criteria section.
• Earth's crust: I've changed this so that the passage now reads, "Five nonmetallic elements—hydrogen, carbon, nitrogen, oxygen, and silicon—collectively make up most of the Earth's crust, atmosphere, oceans and biosphere."

Definition and applicable elements

• First sentence: Changed to, "In general, a nonmetal is a chemical element that can be characterized by low density and high electronegativity."
• Basic oxides: The full passage is, "...and a tendency to produce basic oxides when combined with oxygen.[3] For the first 96 elements, I understand that most of the 73 metals are capable of forming basic oxides.
• Treating metalloids as nonmetals: I have changed this to read, "... due to their predominantly nonmetallic chemistry and weak acidity,[9] and for comparative purposes:

General properties, Physical

• First paragraph: Thanks; I'd never noticed that and will add a footnote.
• Variation in structure and bonding: @Double sharp: As requested I've added a paragraph about this. --- Sandbh (talk) 05:17, 19 October 2023 (UTC)
• Grey As and Sb etc: I understand that grey Sn (a semimetal), Bi and Po form cations in aqueous solution within the normal range of pH values, whereas this is not so for As and Sb.
• Graphite: Now reads, "... good electrical and thermal conductivity is seen only in carbon (as graphite, along its planes), arsenic, and antimony.
• Last para.: the relevant passage now reads: "… the outer electrons are expected to become relatively free to move between atoms ...

General properties, Allotropes

• I believe this has now been addressed with the relocation of the aforementioned hatnote to the top of the article.

--- Sandbh (talk) 05:36, 17 October 2023 (UTC)

For clarity, I'm writing my responses to this below rather than inline. If I don't respond to a point, I'm happy with your response. :) (Though in some cases it seems you may have forgotten to update the article, e.g. there's still no "relatively" in "the outer electrons are expected to become relatively free...".)

• I understand your intention, but my point is that density and electronegativity don't really manage to clearly give you the set of elements that you're planning on talking about by themselves from the start. As I remarked above, if we consider each criterion separately, we get issues like Li (low density but low EN) and Au (high density but high EN). Furthermore, Ge has higher density than Ti (clearly a metal), and about the same electronegativity as Po (by band structure a metal, even if chemically very weak). Whereas the 3D conductivity criterion pretty much gives you almost exactly the set that people actually talk about, with some exceptions when the chemistry makes the classification a bit more awkward. What I'd rather say is that 3D conductivity generally gets you the set of elements that people consider nonmetals, but that authors differ near the borderline, and that other criteria like density and EN have been brought in.
• The crust and atmosphere are so different chemically that considering them collectively might confuse the reader, I think. As for the oceans, once you get past the obviously dominating H₂O, it's suddenly not clear who's dominating because Na⁺, Mg²⁺, K⁺, and Ca²⁺ are as ubiquitous as Cl⁻ and SO₄²⁻. I think the real key point that needs a better expression is that very many of the really famous, common, and biologically important elements in the first few rows are nonmetals – though I guess here a corrective is needed to point out that some metals rival them (Na, Mg, Al, K, Ca, Ti, Fe), and that a few nonmetals are very rare (Se and especially Te).
• Re basic oxides, take chromium for example: it's quite reducing in the +2 state, which is the only oxidation state where it forms a basic oxide. To really make it a tendency, I think we would need to show that the basic oxide is the oxide that is most stable, at the very least. By my count, the elements where you get a basic (not amphoteric) oxide in one of the most stable oxidation states are (stopping at 96 like you do): Li, Na, Mg, K, Ca, Mn, Fe, Co, Ni, Cu, Rb, Sr, Y, Ru, Pd, Ag, Cd, Cs, Ba, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Pt, Hg, Tl, Fr, Ra, Ac, Th, Pa, U, Np, Pu, Am, Cm. This is 47/96, so just under half; and one could argue that effectively it is a bit lower because for a few elements here there are multiple similarly stable oxidation states and only one gives the basic oxide (Mn, Fe, Ru, Pt, U, Np). Also, it seems to me that the main reason it even gets this high is simply that there are an awful lot of rare earths, and they're all similar to each other; a bunch of well-known metals aren't in this list. (Happy to explain my reasoning for any of the inclusions or exclusions. One could widen the bounds of amphotericity somewhat, but then we'd lose even more elements, e.g. you could make a reasonable argument that I shouldn't have included Cu, Cd, Yb, Lu, or Hg.) The point is that many metals form an amphoteric oxide, either instead of, in preference to, or at least in addition to a basic oxide, and this isn't even behaviour that's confined to metals near the borderline. Noting that amphotericity means showing both basic and acidic properties, it seems to me that this tendency is not so clear.
• Do most sources agree that metalloids have predominantly nonmetallic chemistry? Does Rochow think that metalloids are nonmetals, or not? (His view would be more significant if he didn't, on the grounds that authors who think metalloids are nonmetals would be more inclined to define "nonmetallic behaviour" in a way that naturally includes them, but authors who think metalloids are a halfway house would be more inclined to be stricter.) And like I said, what about rhenium? It has essentially no cationic chemistry (this article on its Pourbaix diagram cites Cotton & Wilkinson for that statement), and its aqueous chemistry is dominated by oxides and oxoanions. That seems quite like antimony, yet nobody thinks Re is a metalloid. That suggests that the stated reasoning for why metalloids are being considered nonmetals is incomplete.
• The section is on physical properties. Cation formation is a chemical property. Moreover, it is not even a property that is definitive for being a metal, as evidenced by things like Re; and polonium forms both a simple cation (Po²⁺) and a simple anion (Po²⁻) in aqueous solution. I've at least seen some ambivalence about Po as a metal, e.g. A Dictionary of Chemistry says that "the nearest approach to metallic character [in group 16] is the occurrence of 'metallic' allotropes of selenium, tellurium, and polonium" with the scare quotes. Kitaigorodsky says "it is not clear whether polonium is a metal or a nonmetal", that "of the two dramatically different polymorphic modifications of tin only one (β-Sn) can be classified as a metal", and calls B, Si, Ge, Sb, Te, and Po the metalloids.

Double sharp (talk) 12:06, 17 October 2023 (UTC)

Thank you @Double sharp:

Headsplap! I've rechecked the earlier updates and they should now all be there.

• Density and EN: Per my response to your chat with JJE, above, density and EN (together) work well to give the set of elements within scope of the article. Could you please also refer to the table of Metals and nonmetals sorted by density and electronegativity (EN), in the "Suggested distinguishing section"?
• Crust and atmosphere: These two are mentioned in summary form in the lede, with the detail set out in the Abundance section of the article. The risk of confusion about differing chemistry should be low. The topic sentence of the paragraph in question conveys the idea that this paragraph is about abundance (not chemistry). The latter has already been summarized in the immediately preceding paragraph of the lede. I’m not clear as to the relevance of Na⁺, Mg²⁺, K⁺, and Ca²⁺, and Cl⁻ and SO₄²⁻ since the oceans are ca. 96.5% H₂O (and the crust is ca. 74.3% Si and O).
• Basic oxides: For now, I've changed this from "tendency" to "general capacity". There are no basic nonmetal oxides AFAIK.
• Metalloids and predominately nonmetallic chemistry: I don’t know if "most" sources say so without reading all relevant sources. I do know that it has been known for over 120 years that metalloids have a predominately nonmetallic chemistry (Newth 1894; Friend 1914). On the talk page for this nomination I've listed about 20 extracts from the literature (including Rochow) referrring to the nonmetallic chemistry of metalloids (1894–2016). Rhenium has too high a density.
• Cation formation: There is no mention of this in the "Physical properties" subsection. I agree it is not a definitive property. Po has a truly metallic band structure (no semiconducing allotrope/s). It forms the rose-coloured Po²⁺ cation in solution, displacing hydrogen in the process. The oxide (PoO₂), which assumes the fluorite structure more typical of ionic compounds/metallic oxides, is predominately basic in nature. I see no credible basis to count Po as other than a post-transition metal. It could also be expected to show significant nonmetallic character, as is normally the case for metals in, or in the vicinity of, the p-block.

—- Sandbh (talk) 10:44, 18 October 2023 (UTC)

• See above re my first point. Is taking out these two criteria in particular then a common thing to call a definition, or do sources typically recognise these as two among many properties?
• Well, if these ions are not relevant, then it seems to me that all you are saying when you refer to Earth's oceans is that water is H₂O. If that is truly all there is to the statement, then it seems less confusing to say that water (which is after all the one chemical formula approximately everybody knows) is the most familiar compound containing only nonmetals. As for the crust, while O and Si dominate, the fact that the next seven most common elements in it are all metals – and only then does H appear (C and N are even further down) – seems to mean the statement needs rewording to avoid giving the reader a wrong impression.
• No, but amphoterism (which means having both basic and acidic properties) is not unknown among nonmetal oxides. Consider GeO, Sb₂O₃, I₂O. The middle one is even in the most stable oxidation state for that element.
• Are these 20 extracts representative of the majority view? The fact that metalloids are often included in organometallic chemistry suggests that there may be more nuance to it.
• PoO₂ is amphoteric, it reacts with OH⁻ or NO₃⁻ to form polonite.
• Regarding the last two points: in these sections you are talking about one kind of property. You talk about chemical properties as the reason why metalloids are included: but since these equally well apply to Re, it seems that something needs to be said about density, which the article does not do at that point. (And Sb and Te are not exactly light.) Meanwhile, you indeed only talked about physical properties, to which I commented that by physical properties alone As and Sb were rather examples of physical metals that did not really belong in the discussion the way you had them; they are really examples of physical metals which often get excluded because their chemistry is too unusual for metals. You are the one who countered with cation formation, which is why I responded to that!
• It seems to me from this discussion that the article is attempting to offer a definition of nonmetal based on multiple criteria: nonmetallic chemistry, density, electronegativity. So my question from the beginning is: is it a common thing in RS to take out exactly these tendencies of nonmetals and make them the criteria? My impression is that it is not. If anything, my impression is that people hardly ever actually give criteria and the term is used loosely, unless the author is using the band-structure criterion that's common for physics. And if a criterion is given, it may well be immediately self-contradicted, like here where nonmetals are defined by having 4–7 electrons in their outermost shell, and then Sn and Pb (which fit that definition) are then inexplicably put in the list of metals. Or Steudel, who uses the electrical conductivity criterion, says that C and As fit this definition, and then goes on to admit that actually, those two have an allotrope that fits it and another allotrope that doesn't. (The situation for Sb is not clearly treated; there is a nonmetallic black allotrope of antimony, but it's less stable than white phosphorus. Maybe this is why he thinks Sb and Bi are "purely metallic" in section 10.1.) Indeed, sometimes (Sherwin and Weston 1966) it's used so loosely that the same element (Sb) is called a metal and a nonmetal on two different pages. In which case the article should rather be talking about common and less common inclusions like Metalloid does, rather than attempting to rationalise a situation that the literature may not even be rationalising. The rationalisations are also used to exclude elements that some RS do call nonmetals, which again is not what FA metalloid does: that one mentions quite a lot of rarer inclusions in passing or even in detail, even when they are quite uncommon like C and Al. So I have concerns about the article's philosophy at this point. Double sharp (talk) 11:09, 18 October 2023 (UTC)

@Double sharp:

Philosophy:

The intended scope of the article is elements that are always/mostly or sometimes counted as being nonmetallic. Hence the lede image shows the elements that are always/mostly or sometimes recognised as such, with the last category being the elements most commonly recognised as metalloids.

RS:

• commonly list multiple varying but overlapping properties of nonmetals;
• differ as to what and how they count elements as being nonmetallic; and
• (as noted in the article) lack a universally accepted definition of a non-metal.

About two dozen RS have suggested as many different single criteria to delineate between nonmetals, with results that vary at the margins.

Emsley pointed out the complexity of the task, asserting that no single property alone can unequivocally assign elements to either the metal or nonmetal category

So, the article notes that the numbers of elements involved typically ranges from 14 to 24.

Given the scope of the article, the aim was to generally characterize the nonmetallic elements using one physical and one chemical property. It so happened that low density and high electronegativity gave a good general class portrait. I suppose this is not surprising given there are eleven gaseous nonmetallic elements and that nearly all nonmetallic elements are located towards the top right of the periodic table.

Even so, the article makes clear that the family portrait is not frozen in print, with the article’s use of words and expressions such as, "generally", "predominantly located" and "primarily occupied".

In my experience about 50% of textbooks include specific lists of metalloids and of those Al was counted as a metalloid 9.3% of the time. Thus, Al is counted as a metalloid about 5% of the time and as a metal 95% of the time.

If you like, there may be room for an "Outliers" sub-sub-section at the end of the Metalloids section. This could address Po, Al, C, Bi, Be, Sn, Ga and Pb, all of which have been identified as metalloids in at least one source, per the Lists of metalloids article.

That could perhaps address your philosophical concern, without unduly encumbering the article.

--- Sandbh (talk) 00:51, 20 October 2023 (UTC)

Comments from YBG

I cannot find the pace where this was discussed here, so I’ll register by disagreement to two recent changes:

• special:Diff/1180516134 characterized —> that can be characterized— seems unnecessarily wordy
• special:Diff/1180514553 moved the properties of the most stable forms in ambient conditions unless otherwise mentioned from section hatnote in the appropriate context to the dab hatnote at the top where in my experience only specifically disambiguating info is shown. Unless there is another page that treats the less stable allotropes, or non-standard conditions, the extra phrase does not belong in the dab hatnote at the top.

YBG (talk) 05:25, 17 October 2023 (UTC)

Thank you YBG.

• This change was made in response to Double sharp's criticism (above) about the first sentence of the Definition and applicable elements section.
• I've relocated the hatnote at the top of the article to the top of the Definition and applicable elements section, and reworded it accordingly.

--- Sandbh (talk) 05:55, 17 October 2023 (UTC)

Ta YBG (talk) 14:06, 19 October 2023 (UTC)

A couple of notes:

1. Some time back I recall reading the article and thinking it was vaguely implied that the metalloids are main or only reason for NM lists varying. I’m definitely not asking for any change in the article, but I wonder if you could let me know if this is so, and if not, what are the non-metalloids that straddle the fence? Again, this is just personal curiosity and definitely NOT a request to change anything.
2. Could the lede avoid stating anything about whether properties are characteristic or not? Here’s a possible idea:

   Current

   A nonmetal is a chemical element generally characterized by low density and high electronegativity (the ability of an atom in a molecule to attract electrons to itself). They range from colorless gases like hydrogen to shiny solids like the graphite form of carbon. * * *

   Proposed

   Nonmetals - chemical elements other than metals - generally have low density and high electronegativity (the ability of an atom in a molecule to attract electrons to itself) and range from colorless gases like hydrogen to shiny solids like the graphite form of carbon. * * *

Just a thought, not fully formed. Definitely needs input from other reviewers. YBG (talk) 14:01, 19 October 2023 (UTC)

Thanks YBG. You may read have a passage in the lede that says, "As some elements have a marked combination of metallic and nonmetallic properties, lists of nonmetals typically vary from 14 to 24 members."

I've changed the lede to say:

A nonmetal is a chemical element generally characterized by, among other properties, low density and high electronegativity (the ability of an atom in a molecule to attract electrons to itself).

I feel there should be no surprise here given 11 nonmetallic elements are gases, and that nearly all nonmetallic elements are found towards the top right of the PT, where EN values peak.

There has to be some way of capturing the scope of the article and this seems to be (a) accurate, with wriggle room provided by the "generally"; (b) relatively inclusive; (c) balanced; (d) concise; and (e) congruent with the location of nonmetals in the PT.

--- Sandbh (talk) 03:41, 20 October 2023 (UTC)

Overall evaluation

First of all, two caveats: I am coming to this party late, and recognize that consequently owe an apology and should have no expectation that my concerns receive the same attention as those who engaged earlier. And second, I have been reviewing it without specificity referring to the criteria; just my general familiarity with WP policies, with the subject matter, and with what makes an article readable.

I am generally pleased with the state of this article. Occasionally there is some clumsy wordiness caused by the need for precision and a worthy desire to avoid making generalizations that are false for one or two of this harlequin collection.

I have one major concern and a number of suggestions. I would have had many more suggestions, but where I could see a simple path forward and I thought the likelihood of disagreement slight, I simply edited the article.

I am leaning toward recommending promotion. What will push me over the top is:

1. A resolution of my major concern, either by the article being changed or by one or two reviewers giving good reasons why this should not be a concern.
2. An acceptance of the topic sentence by most or all reviewers. I’ve offered a suggestion below which I think might be an improvement and might alleviate any remaining concerns.
3. A resolution of my remaining suggestions, either by the idea being implemented or by the nominative giving a reason why it should not be.

YBG (talk) 06:22, 21 October 2023 (UTC)

Biggest concern

My biggest concern is related to the pairing of nonmetal classes with a “complementing” set of metals.

• The pairing of nonmetal classes and metal classes is a beautiful and symmetric, but I suspect it is a bit fringe to be so prominently displayed in this article. There are RS listed in the pictures that presumably show that a given author compared a specific nonmetal category with a specific metal category. But the sources are different for each one.

Let me draw a comparison. In Classical Planet § Alchemy we see a list of planets and corresponding metals. The entire set of pairings is well attested in RS.

But what if I only found one RS that compared the Sun to gold, a different RS that compared the moon to silver, and a third that compared Mercury to mercury, and a fourth that compared Venus to copper, a fifth, Mars to iron, a sixth, Jupiter to tin, and a sixth, Saturn to lead? In this case, I believe it would be violate WP:SYNTH to prominently display the whole set of pairings as though it were some sort of organizing principal.

The pairings of nonmetal categories with metal categories appears to be this same sort of synthesis, and so I say, no matter how beautiful and symmetrical this is, it does not belong in a WP article. I would be very interested to know what other reviewers think of this concern. YBG (talk) 06:22, 21 October 2023 (UTC)

@Graham Beards, Michael D. Turnbull, Jo-Jo Eumerus, Double sharp, and Sandbh: Please consider commenting on this. I will consider this concern resolved if either (1) the nominator removes the info about complementary sets of metals, or (2) no other reviewer voices a concern about this, or (3) one other reviewer gives what they (not me) consider is a good reason that this is not a concern. YBG (talk) 13:37, 21 October 2023 (UTC)

I agree with your concern. Not only is each comparison cited to a different source, but the last one (unclassified to transition) is straightforwardly SYNTH (see ref. 158; neither source quoted actually spells out the connexion). Double sharp (talk) 14:11, 21 October 2023 (UTC)

@Jo-Jo Eumerus, Double sharp, and YBG: I've added a citation that mentions the four complementary sets. --- Sandbh (talk) 03:55, 22 October 2023 (UTC)

WP:NOT says

A Wikipedia article should not be a complete exposition of all possible details, but a summary of accepted knowledge regarding its subject. Verifiable and sourced statements should be treated with appropriate weight. (emphasis added)

Citing your own article suggests that someone as well read as you could find no other RS that organizes things this way, which seems to prove my point: this is a novel idea not yet ready for WP. I suggest that it is best to leave it out for now. In a few years, if this organizing scheme is as useful as it is beautiful, other authors will pick it up and it can be included with no objection. YBG (talk) 04:28, 22 October 2023 (UTC)

Thank you YBG.

There is nothing "novel" in this.

The background to the complementing sets is that the pairing of metals and nonmetals, and alkali metals and halogens, forms a foundational technique in chemistry education:

... we focus mainly on the gross structure – the metals are here, the non-metals are there, and so on. Once they have grasped this, you can start to show that there's some order to it. We talk about the Group 1 alkali metals and start to see that they're all similar in some way. Then at the other extreme there are the ...halogens. The idea that the table shows us how to group similar elements starts to come together in this way.

Niki Kaiser (2019)

Notre Dame High School, Norwich, UK

There is a long history in the literature of complementing sets, for example:

What, in general, is the difference between active metals, less active metals, less active non-metals, active non-metals, and inert gases…?

--- Friedenberg EZ 1946, A Technique for Developing Courses in Physical Science Adapted to the Needs of Students at the Junior College Level, University of Chicago, Chicago, p. 230

For more recent references there are:

Describe how groups of elements can be classified including highly reactive metals, less reactive metals, highly reactive nonmetals, less reactive nonmetals, and some almost completely nonreactive gases.

--- Padilla MJ, Cyr M & Miaoulis I 2005, Science explorer (Indiana Grade 6), teachers's edition, Prentice Hall, Upper Saddle River, New Jersey, p. 27

Those [elements] classified as metallic range from the highly reactive sodium and barium to the noble metals, such as gold and platinum. The nonmetals…encompass the…the aggressive, highly-oxidizing fluorine and the unreactive gases such as helium.

--- Weller et al. 2018, Inorganic Chemistry, 7th ed., Oxford University Press, Oxford, preface

A similar pattern occurs along the periods:

Across each period is a more or less steady transition from an active metal through less active metals and weakly active non- metals to highly active nonmetals and finally to an inert gas.

--- Beiser A 1968, Perspectives of modern physics, McGraw-Hill, New York

The pairing of the noble metals and gases is mentioned in no less a reputable source then Wiberg.

The pairing of the post-transition metals and the metalloids occurs even in a popular science book by Adrian Dingle (2017) who has written extensively on PT matters:

[With] no-doubt metals on the far left of the table, and no-doubt non-metals on the far right ... the gap between the two extremes is bridged first by the poor [post-transition] metals, and then by the metalloids—which, perhaps by the same token, might collectively be renamed the "poor non-metals".

That just leaves the transition metals and the unclassified nonmetals, both of which are bridging in nature, as observed by Atkins, and Welcher.

I won't fuss about this; if need be it'll be easy enough to revert the complementing sets.

That said, could you please consider the following:

• The long history of the idea of parallels among the elements between e.g. active metals, less active metals, less active nonmetals and active nonmetals.
• The cited article was published in a reliable, peer reviewed journal.
• It's been cited seven times by other authors.
• Each complementing set has been cited in other reliable sources.
• An encyclopedia, as I understand the nature of WP, collects and presents what is understood to be factual information, as is the case here.

--- Sandbh (talk) 13:08, 22 October 2023 (UTC)

New idea for 1st sentence

I think the issues with the first sentence could be resolved by getting away from trying to define nonmetal and instead concentrating on description. Here is an idea:

The nonmetals are a set of chemical elements that are not metals; between 14 and 24 are included depending on the definition being used.

YBG (talk) 06:22, 21 October 2023 (UTC)

@Graham Beards, Michael D. Turnbull, Jo-Jo Eumerus, Double sharp, and Sandbh: Please consider commenting on this. I will consider this suggestion resolved if either (1) my suggestion or something similar is implemented, or (2) no other reviewer voices a desire for this change, or (3) one other reviewer gives what they (not me) consider is a good reason that this change not be implemented. YBG (talk) 13:40, 21 October 2023 (UTC)

That seems good for me. Jo-Jo Eumerus (talk) 13:57, 21 October 2023 (UTC)

I agree in principle, except that I'm not sure that all authors are even using definitions. To me, the word "definition" implies that (1) you are giving a set of criteria instead of baldly listing without explanation what elements you're going to include, and that (2) you then actually take that criterion seriously and include only elements that fit it. This, in my experience, doesn't always happen. (Above I gave examples. Even Steudel does not exactly succeed in (2), because of the allotropy problem.) I think it would be better to say something like A nonmetal is a chemical element that mostly lacks metallic properties. There is no universally agreed definition of the term, both because different authors prioritise different properties, and because some elements naturally fall at the borderlines. There is a general consensus on seventeen elements as nonmetals, though some authors may include more or less. The borderline elements are often called metalloids; some authors consider them a subclass of nonmetals, thus increasing the number of nonmetals further. Feel free to improve the wording, but I think this gets at the point.

(The seventeen are the "universal" 14, plus C, P, Se, which are only minority inclusions into the metalloids. They are the ones highlighted in the lede graphic, minus rare and unstable At.) Double sharp (talk) 14:24, 21 October 2023 (UTC)

@YBG, Jo-Jo Eumerus, and Double sharp: Firstly, any concerns about the 1st sentence could easily be resolved by using either YBG's suggestion or that of Double sharp (plus the rest of the proposed sentences).

There are some other considerations however:

1. The proposed 1st sentence describes by "negation" rather than by affirmation.
2. Affirmative descriptions provide better clarity.
3. The sources are about 50:50 between defining nonmetals as (i) elements either not having the properties of a metal or (ii) in terms of more specific properties.
4. A description by affirmation would seem to be preferred.

I *quite* like Double sharp's set of words.

--- Sandbh (talk) 00:23, 22 October 2023 (UTC)

Sure, affirmative descriptions are better when there is an agreement between sources on them. But is there? Different sources are simply using different criteria. (And sometimes not actually following them.) At least I'd imagine that sources would agree that nonmetals are not metals. It is kind of already in the name. Planet offers a precedent: the first sentence says stuff everyone would agree with, and later in the lede it talks about different criteria people have used. (Compare, after all, the situation with how people treat clearing the neighbourhood and deuterium burning for planets. I do understand that planets are harder to define, because there's essentially no limit to how many we could discover and exoplanets have a way of upending our prior assumptions, whereas for elements it's another story because we're not going to be able to physically investigate bulk astatine soon, much less the superheavies. Still, the idea is similar, in that different people are prioritising different criteria.) Double sharp (talk) 02:22, 22 October 2023 (UTC)

@Double sharp: I suspect there is agreement between the sources in the sense that they all draw on (prioritise?) a few or several properties from the same big set of all properties associated with nonmetals. There are of course differences in just which few or several properties each author chooses. Does the question then become which few properties can do a reasonable job of more or less encompassing the big set? --- Sandbh (talk) 04:05, 22 October 2023 (UTC)

@Sandbh: I don't think we should be the ones making that decision. I think we should rather give the list, which is mostly agreed on (modulo what exactly people make of metalloids), and then mention tendencies that people have used as criteria. Double sharp (talk) 04:07, 22 October 2023 (UTC)

@Double sharp: OK; if you feel there's a need for more tendency-speak in the article, that should be doable. --- Sandbh (talk) 04:26, 22 October 2023 (UTC)

Other suggestions

1. Types. What is the difference between classifying metalloids “as nonmetals”[123] and “as a sub-class of nonmetals”[124]? Why not treat these two as the same?
2. Abundance. I wonder if the chart could be expanded to include a row about the universe, with the H / He / O percentages. This would require some rewording of the chart header.

   Note: I have copy edited this section a bit, trimming unneeded wordiness and relegating the irrelevant details about non-ordinary matter to a note.

3. Extraction. This would be a fun place to insert another PT extract, with five colors (for the five sources) and two shadings (solid for exclusively, striped for mainly)

YBG (talk) 06:22, 21 October 2023 (UTC)

@Sandbh: I will consider each of these suggestions resolved if either (1) you implement the idea, or (2) you give what you (not me) consider is a good reason not to implement the idea (or not to implement it now). YBG (talk) 13:46, 21 October 2023 (UTC)

PS, I’m willing to help in any of these if you provide me with the needed data. YBG (talk) 13:50, 21 October 2023 (UTC)

@YBG: I've implemented #1 and #2. I'll have to get back to you about #3. --- Sandbh (talk) 03:31, 22 October 2023 (UTC)

Thank you. Regarding a PT for extraction, I see several more-or-less equally acceptable resolutions:

1. You state that you don’t think such a PT should be included.
2. You implement such a periodic table.
3. You provide the data and references necessary somewhere (article talk page? footnote? user TP? elsewhere?) so that other editors could implement such a PT.
4. You simply state that you’d like to do this after this FAC is closed one way or the other.

YBG (talk) 11:24, 22 October 2023 (UTC)

Comment to Coordinators

@FAC coordinators: This has turned into a Peer Review and the FAC should be archived. It's not fair on reviewers or coordinators to expect them to wade through all this. Candidate articles are expected to be FA ready or very close at the time of nomination, but despite countless earlier nominations, it's not there. It some instances it's getting worse. See this in the Lead for example: "There is no universally agreed definition of the term... there is no universally accepted definition of a nonmetal". How many times do the readers need to be told? Graham Beards (talk) 14:54, 22 October 2023 (UTC)

@Graham Beards: Polite comments. With respect, I cannot control whether or not reviewers choose to do a line-by-line review, as I did with the TRAPPIST-1 FA nomination, which was promoted, after my review was acted on. Considerable signs of movement towards consensus to promote Nonmetal had occurred. There was a support from Mirokado; Michael D. Turnbull was inclined to support. YBG was inclined to support. Double sharp was neutral but was inclined to support subject to a few adjustments. No hard feelings. --- Sandbh (talk) 22:56, 22 October 2023 (UTC)

• Closing note: This candidate has been archived, but there may be a delay in bot processing of the close. Please see WP:FAC/ar, and leave the {{featured article candidates}} template in place on the talk page until the bot goes through. Gog the Mild (talk) 15:19, 22 October 2023 (UTC)

The above discussion is preserved as an archive. Please do not modify it. No further edits should be made to this page.