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    • 28 Sep 2024Lectka enantioselective beta-lactam synthesis (talk · edit · hist) AfDed by Mdewman6 (t · c) was closed as redirect by OwenX (t · c) on 13 Oct 2024; see discussion (4 participants; relisted)
    • 06 Aug 2024Homogeneity and heterogeneity (talk · edit · hist) AfDed by Fgnievinski (t · c) was closed as keep by Liz (t · c) on 13 Aug 2024; see discussion (6 participants)
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    Potassium hexacyanidoferrate(III)‎... wha?

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    This tortured IUPAC nomenclature. Unfortunate. Practicing chemists do not use this term. --Smokefoot (talk) 16:51, 13 June 2024 (UTC)[reply]

    Any time I've seen this out in the wild (I'm sure I have somewhere) it's been potassium ferricyanide which is where it was just moved from. If it really had to be at the IUPAC name, shouldn't it get moved to Tripotassium;iron(3+);hexacyanide? There's a reason the water page isn't called Oxidane.
    Also possibly relevant, Potassium trichloridocuprate(II). Reconrabbit 20:20, 13 June 2024 (UTC)[reply]
    Even Potassium hexacyanoferrate(III) was much more commonly used. I have moved the page back to potassium ferricyanide which is more commonly used by about a factor of 1000. Wikipedia policy is to use the most frequently used name rather than official (here closest to IUPAC). Letting @JWBE: know about reversion of the move. Graeme Bartlett (talk) 22:48, 13 June 2024 (UTC)[reply]
    Greetings, Smokefoot! I have also found several instances of this, like with DIBAL and Red-Al. I am pretty sure that it would be fine to refer to DIBAL as, well, DIBAL. However, do you think it appropriate to refer to Red-Al as Red-Al due to it being a trade name? Pygos (talk) 13:19, 14 August 2024 (UTC)[reply]

    RfC: On discovery of the 23 nonmetals

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    Should this content on the discovery of the 23 nonmetals be removed from the nonmetal article?

    RfC is here. --- Sandbh (talk) 13:39, 23 July 2024 (UTC)[reply]

    Access to ACS journals via The Wikipedia Library

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    Currently, the TWL offers comprehensive access to literature ressources relevant to chemistry. The likely most important collection of scientific journals in the field of chemistry, which also partially covers neighboring disciplines including physics, biology, materials science or nutritional science, is published by the American Chemical Society (ACS). Unfortunately, TWL does not offer access to the ACS journals. In the Wikimedia Phabricator's TWL area the potential subscription to the ACS journal collection is currently listed under "Prospects". The number of Wikipedia authors supporting such a subscription is apparently relevant to the prioritization of new TWL subscriptions. Therefore, my request would be that anyone, who is also interested in getting access to the ACS journals, supports the proposal to subscribe to the ACS journals. For this purpose, log in to TWL, go the "suggest a collection" page (https://wikipedialibrary.wmflabs.org/suggest/), scroll down to the ACS entry and click on "Support". This doesn't cost much... Thanks for any support! Espresso robusta (talk) 13:42, 4 August 2024 (UTC)[reply]

    @Espresso robusta Great suggestion! Unfortunately, the upvotes are currently only at 30, which still places us quite low in the list. Mike Turnbull (talk) 16:50, 4 August 2024 (UTC)[reply]
    @Espresso robusta thanks for suggesting! I have an ACS membership so get some access that way but for scientists who don't have access via industry or university it would be a great resource. 34 upvotes isn't too bad for a niche area... Nnev66 (talk) 17:03, 5 August 2024 (UTC)[reply]

    Ethanol vs. methanol

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    Hello WikiProject Chemistry! Could I get someone's eyes on 2016 Irkutsk mass methanol poisoning to make sure I've characterized these two substances correctly? The article is currently at WP:FAC. (And would anyone be game to stage and take a comparison photo of the two to demonstrate how similar they appear...?) Ed [talk] [OMT] 14:59, 13 August 2024 (UTC)[reply]

    I have stock of both chemicals around, I can easily do a photo of each in side-by-side labeled vials later today. We've generally shied away from those on chemical articles (so I'm not surprised we don't already have each in c:Category:Methanol and c:Category:Ethanol), since they're both identical appearance clear colorless liquids. But obviously that comparison is relevant here. DMacks (talk) 15:23, 13 August 2024 (UTC)[reply]
    @Dmacks: Thank you so much! A photo was a great suggestion from a reviewer at the FAC and will help to communicate how these people unknowingly drank methanol. Ed [talk] [OMT] 15:31, 13 August 2024 (UTC)[reply]
    @DMacks: fixing ping. Ed [talk] [OMT] 17:04, 13 August 2024 (UTC)[reply]
    I actually think that showing ethanol and methanol side-by-side is a great idea because (not despite) them being both identical appearance clear colorless liquids. That would illustrate rather beautifully why the poisonings happen. Jo-Jo Eumerus (talk) 07:23, 14 August 2024 (UTC)[reply]
    They also have similar odours, which is rather harder to show in an article here! Concluding that the similarity in appearance was the reason for the poisonings would be original research: those who drank the stuff knew they had purchased bootleg "bath oil" to avoid the tax on alcohol. Mike Turnbull (talk) 12:01, 14 August 2024 (UTC)[reply]
    Sorry for the delay, @The ed17 and Jo-Jo Eumerus:! Here you go: File:Methanol ethanol vials.jpg. Mike Turnbull makes a good point, that there should be a cited statement that they cannot be distinguished by appearance. This is mentioned without cite in methanol#Toxicity, and surprisingly not even mentioned at all in methanol toxicity. The statement in the FAC article is "Methanol is cheaper than ethanol, and the two cannot readily be distinguished." but the given NYTimes ref does not appear to mention anything related to that second clause. DMacks (talk) 06:28, 18 August 2024 (UTC)[reply]
    @Michael D. Turnbull and DMacks: Oof. So I dug into that and found the phrase was added just a day after the article was created, and I never noticed that the info didn't match up with the attached ref. Thank you for your diligence, and to Dmacks for the photo. I've added a Britannica reference to replace it -- I was surprised to find that it wasn't the easiest thing to find a replacement ref for. Ed [talk] [OMT] 23:35, 18 August 2024 (UTC)[reply]
    Thanks for tracking down a source! There's so much common knowledge that isn't stated explicitly in discoverable RS:( DMacks (talk) 23:38, 18 August 2024 (UTC)[reply]

    The structure of tantalum pentoxide

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    File:Kristallstruktur_Triuranoctoxid.png

    Tantalum pentoxide (Ta2O5) currently shows the crystal structure for Triuranium octoxide (U3O8). We frequently use use crystallographic archetypes in this way, but looking closer, I don't think this one is right. The stoichiometries don't add up, the uranium compound is mixed valance (V,VI) but the Tantalum one isn't. The imagine has been used this way on all the non-English pages as well. Project Osprey (talk) 15:38, 16 August 2024 (UTC)[reply]

    Let me see what I can find. Usually Ben Mills does these images. --Smokefoot (talk) 16:03, 16 August 2024 (UTC)[reply]

    Chemical formulas on Wikidata

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    During a discussion on Wikidata (see https://www.wikidata.org/wiki/Wikidata:Property_proposal/chemical_formula), it came out pages like https://en.wikipedia.org/wiki/C15H20O4 would benefit from the proposal, maybe of interest for people here to add their opinions? AdrianoRutz (talk) 08:40, 29 August 2024 (UTC)[reply]

    {{ping| AdrianoRutz} What exactly is the proposal? These discussions seem to be dominated by editors who have little cred in chemical editing.--Smokefoot (talk) 13:21, 29 August 2024 (UTC)[reply]
    It looks like the proposal is to convert every chemical name into a formula. As shown in the example: 2-hydroxy-5-octanoylbenzoic acid (Q209407), abscisic acid (Q332211), and Santonic acid (Q7420590) will all be changed to be defined as C₁₅H₂₀O₄ (Q129998552). This seems like a bad idea. It's noted in the first comment that the general formula would be "isotope-agnostic", but subclasses could be made for each isotope. Never mind what the implications are for structural isomers. I could be completely misconstruing what the proposal is though because it isn't clear to me either. Looking at it again it appears the proposal is to, instead of defining each chemical's formula as a unique string, defining a specific item for every single chemical formula that can be shared between structural isomers and isotopes. Reconrabbit 15:30, 29 August 2024 (UTC)[reply]
    The proposal is about switching the actual way chemical formulae are modelled internally in Wikidata. Currently, they are strings and not items and this comes with many disadvantages for efficient querying and data redundancy. Having them as items on Wikidata would allow more refined queries (such as "give me all chemical entities that contain X carbon, Y hydrogen and Z oxygen", for example) and drastically reduce the number of "mass" statements needed as these could move from the chemical entity item to the formula item and thus help maintainers focus on less, higher quality masses.
    I will pass above you "street cred" statement. No place for such things, but I invite you to look at the Chemistry project on Wikidata and see the beautiful things some fantastic contributors are doing. AdrianoRutz (talk) 09:33, 23 September 2024 (UTC)[reply]
    This is also highly relevant to Wikipedia, as some existing pages about chemical formulas (https://en.wikipedia.org/wiki/C15H20O4) linked to different chemical entities could heavily benefit from it, or even the chem info box. AdrianoRutz (talk) 09:36, 23 September 2024 (UTC)[reply]

    Carbocation business

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    I am contemplating changes affecting at least 4 articles. The evolving plans are described at Talk:Carbocation#Merge proposal:

    1. relocate most, not all, carbenium ion (R3C+) content from carbocation to carbenium ion article.
    2. relocate most, not all, carbonium ion (R5C+) content from carbocation to the carbonium ion article with a sections on some individual nonclassical carbocations such as 2-norbonyl cation and many others.
    3. convert carbocation into a concise summary of these two kinds of cations, keep the "history" and the "nomenclature".
    4. move 2-Norbornyl cation to Norbornyl cation debate to incorporate all that history. This debate, once a "thing", was settled when the X-ray structure was announced in 2013. It is doubtful that many readers want to wade through that history. 2-Norbornyl cation would redirect to carbonium ion#2-Norbornyl cation together with related cations such as homoallyl cation and cyclopropyl methyl cation. I am not an expert on these topics in case you are wondering.--Smokefoot (talk) 16:34, 31 August 2024 (UTC)[reply]
    I would appreciate the "debate" to be a separate article, as it gets difficult to read what the current beliefs about it are with that massive history and theory included. But I think 2-Norbornyl cation has enough material to be its own article. Graeme Bartlett (talk) 04:48, 1 September 2024 (UTC)[reply]
    I like it! For (3), don't forget to include vinyl cation, and a mention of the false teaching tool of drawing acylium ions with a carbonyl-carbocation resonance form (see doi:10.1021/ed5002152). DMacks (talk) 06:50, 1 September 2024 (UTC)[reply]
    Sounds good. There is a problem with the lead in carbenium ion "But IUPAC confuses...." which is only referenced to the IUPAC definition. This needs to be re-written carefully to avoid being WP:OR. Carbocation#Definitions may clear this up. Mike Turnbull (talk) 15:03, 1 September 2024 (UTC)[reply]
    I will follow the suggestions above. Also, this thing showed up: nonclassical ion, which could be a home for relatives of 2-Norbornyl cation-like species or could be redirected to carbocation. And then Pyramidal carbocation. Someone might inspect (remove???) the extensive calculations and theory, we dont do that kind of analysis typically.--Smokefoot (talk) 15:42, 1 September 2024 (UTC)[reply]
    If you think you can improve it then be bold. If you have reservations, then maybe do the new pages in a sandbox and we can see later? Some comments: (1) We normally use the simplest example of a functional group as an archetype for our descriptions, but methenium basically doesn't exist. It might be easier to use the t-butyl cation. Butylation is big business, so it is relevant and there may be better references. (2) The alkylation of alpha-olefins to give linear alkylbenzene illustrates the behaviour of secondary carbenium ions (i.e. they clearly exist, but the the charge moves freely up and down chain, giving a range of products). The Wagner–Meerwein rearrangement for the industrial production of vitamin E (not shown on our page) is a nice example of this willingness to rearrange being put to practical use. The presence of a 3c-2e bond in some protonated alkenes (ethanium) seems to be at odds with Markovnikov's rule as it implies the cations can be terminal-ish, I'm not sure what the reality is there (do we ever see any completely linear alkylbenzenes?) --Project Osprey (talk) 21:41, 1 September 2024 (UTC)[reply]

    Guidelines on chemistry solubility?

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    I originally posted this at the help desk: Wikipedia:Help desk/Archives/2024 September 1 - Wikipedia but was recommended to post this here.

    On the MoS for line equations it merely says "Do not include phase definitions unless they are absolutely essential". Normally, the states of matter as written as, for example, AgCl(s), but on the silver chloride page the precipitate is written as a down arrow for 2 equations and with a subscript for the remaining. Does Wikipedia have a preferred style?

    Also, on some pages, like silver phosphate, as well as the main article for solubility product, the solubility product is written with units at the end of it, when it is usually treated as a dimensionless quantity. Is there a preferred style? SecretSpectre (talk) 06:30, 5 September 2024 (UTC)[reply]

    You have already found WP:Manual_of_Style/Chemistry#Line_equations, which is where any agreement on the preferred style is likely to have been recorded. You can suggest/discuss additions to the guidelines right here, if you like. IMO if you are making a proposal to fix on a preferred style, you also need some way to identify by a search where we would need to change existing articles in the "wrong" style. Mike Turnbull (talk) 12:13, 5 September 2024 (UTC)[reply]
    The first question (states) is actually two ideas. One idea is whether to use the parenthetical letter vs up/down-arrow in an equation based on the merits or context of that equation. My position is that both are acceptable, but the arrow emphasizes that there is a phase change (such as "becoming a solid" or "coming out of solution") vs just being a solid. The other idea is the general goal of Wikipedia:Consistency, such as using the same thing within any one article. But I think consistency should always be secondary to clear and correct meaning, so I'm having trouble thinking of a time that both would be equally appropriately meaningful and still worth including. DMacks (talk) 18:05, 5 September 2024 (UTC)[reply]

    Errors in a Periodic Table on Wikimedia Commons

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    It was brought to my attention that File:Periodic Table Of Elements Black And White.svg on Commons has multiple errors. There has been a comment on the file's talk page about the wrong atomic numbers since 2020. Does anyone know how to either get the file fixed or deleted? See below for comments copied from the file's talk page.

    The elements Te, and Ir -> Hg all have the wrong atomic numbers assigned to them. Griceylipper (talk) 13:57, 12 December 2020 (UTC)[reply]
    I noticed Thallium has "TI" (capital T, Capital I) as its symbol, not Tl (capital T, lower case l) - look at Chlorine (Cl) or Aluminum (Al) to see what a lower case "l" looks like. Ruhrfisch (talk) 18:37, 6 September 2024 (UTC)[reply]

    Thanks, - Ruhrfisch ><>°° 18:42, 6 September 2024 (UTC)[reply]

    @Ruhrfisch That file doesn't seem to be used in any article in any language version of Wikipedia (see its Commons page) and the uploader hasn't made any contributions there since 2016 when it was uploaded. You can nominate the file for deletion using the menu on the left of its file page on Commons. Mike Turnbull (talk) 19:26, 6 September 2024 (UTC)[reply]
    @Griceylipper Apologies, I see it was you who made the original post, not Ruhrfisch. Mike Turnbull (talk) 19:28, 6 September 2024 (UTC)[reply]
    For now I have added the Disputed chem template to the page so that others are warned about the problem and are less likely to attempt to use it. File:Periodic Table Of Elements.svg by the same uploader had similar issues, but most of the errors have already been corrected (Te still has the wrong atomic number though, so I've marked that one as disputed too). Marbletan (talk) 19:34, 6 September 2024 (UTC)[reply]
    I suggest just nominating both for deletion, I think there are enough others. Ldm1954 (talk) 20:33, 6 September 2024 (UTC)[reply]
    Thanks everyone - I have nominated the Commons file for deletion, here: c:Commons:Deletion requests/File:Periodic Table Of Elements Black And White.svg. - Ruhrfisch ><>°° 01:27, 7 September 2024 (UTC)[reply]
    The link is c:Commons:Deletion_requests/File:Periodic_Table_Of_Elements_Black_And_White.svg Mike Turnbull (talk) 10:18, 7 September 2024 (UTC)[reply]
    Thanks, I fixed the link in my original comment. I've not been very active recently and did not know the "c:" prefix trick. Thanks again, - Ruhrfisch ><>°° 00:45, 8 September 2024 (UTC)[reply]

    Featured article review of Heavy metal (elements)

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    I have started a Featured article review of Heavy metal (elements), please follow the link to the source. Based upon reading the sources too many did not validate; Johnjbarton also had some serious criticisms. Ldm1954 (talk) 23:28, 6 September 2024 (UTC)[reply]

    N.B., the main page is Wikipedia:Featured article review#Heavy metal (elements), the link above goes directly to a page just on this FAR. Ldm1954 (talk) 00:20, 7 September 2024 (UTC)[reply]

    Hi! The regulars are CFD are not chemistry experts, so we would really appreciate your input at Wikipedia:Categories for discussion/Log/2024 September 15#Category:Chemical looping technologies. No knowledge of CFD policies/procedures necessary – the participants have a question about whether Chemical looping combustion and Chemical looping reforming and gasification belong in Category:Chemical process engineering or Category:Chemical processes. Best, HouseBlaster (talk • he/they) 02:03, 15 September 2024 (UTC)[reply]

    Made-up chemical names!

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    Hi! I wanted to let you all know of something I came across while browsing today. I removed multiple "alternate names" for very common chemicals that I believe are completely made up, all added in 2023 by the same IP editor:

    None of these names appeared in any legitimate chemical context that I could find aside from a couple of obvious typos, so I went ahead and removed them, but that user has some other questionable naming edits that I wasn't 100% sure about and it seems like there may be others doing the same thing (I think this is likely the same person).

    Thanks, Cystathionine (talk) 07:11, 17 September 2024 (UTC)[reply]

    They would be in the category of WP:Original research. Did any get created as redirects? Graeme Bartlett (talk) 09:03, 17 September 2024 (UTC)[reply]
    The good news is that they're all simple article edits — no redirects — by one or more well-meaning but unhelpful editors (no malicious vandalism). The bad news is that there appear to be other IPs in this cluster. Cystathionine found 42.117.40.173 and 115.74.10.44, and 115.74.4.110 looks like another one. Pattern seems to be edits in early-mid 2023, with no commit messages, by IPs that geolocate to Vietnam (albeit Hanoi and Vũng Tàu, so they might not be exactly the same editor).
    Here's a list of edits from the first two IPs that hadn't been reviewed yet — I'd appreciate if someone else could have a look over my doco here and clean up any remaining mess:
    • Dibenzene in Biphenyl — seems incorrect to me, reverted.
    • Xenene in Biphenyl — valid, kept.
    • Benzoylic acid and Carboxylbenzene in Benzoic acid — both names appear to be rare but valid, kept.
    • Dicarboxylbenzene, Carboxylbenzoic acid, 1,2-Phenylenedicarboxylic acid, Phenylene-1,2-dicarboxylic acid in Phthalic acid — 1,2-dicarboxylbenzene would be valid (but is not what they added), other two aren't really used, reverted.
    • Carbonous acid in Formic acid — not just invalid, but refers to a different compound, reverted; have also removed Isocarbonous acid (added in 13:41, 5 April 2017) as this isn't in PubChem or ChemSpider (or anything else either); could also have added back Aminic acid (rare but valid) but elected not to.
    • Acetocarboxylic acid in 00:43, 3 February 2023 and 00:44, 3 February 2023 (as Acetonoic acid already removed, as well as Acetoic acid, Oxoacetol in 03:39, 4 February 2023 already removed) — invalid, reverted. Also noticed Acetoic acid had been removed from the chembox but not the article body — fixed.
    • Phosphinol in Phosphinous acid — invalid, reverted.
    • Their edits for Lead(IV) acetate and Lead(IV)_chloride actually seem to be OK
    • Plumbous acid in Lead(II) hydroxide — invalid, reverted.
    • Pentylene (and other changes) in Pentene — perhaps technically correct but unhelpful, reverted.
    I haven't had a proper look at the ones in 115.74.4.110 but I think most (though not all) of these need to be reverted too — would someone else be able to have a look over those? Preimage (talk) 14:20, 17 September 2024 (UTC)[reply]
    @Cystathionine Well spotted. ChemSpider and Pubchem both have extensive lists of synonyms for chemical names. If any of the ones the IPs added aren't there, they should certainly be removed and even if they are present in those databases, Wikipedia's chemboxes don't need to include every possible alternate name. Mike Turnbull (talk) 13:16, 17 September 2024 (UTC)[reply]
    Google Patents turns up a couple East Asian patents which Google translates as using "acetoic acid"; compare e.g. TW I462957B  vs US 8952099B2  - though espacenet does not use "acetoic acid" in its own machine-translated version of the Taiwanese patent. As both IP addresses mentioned are from Vietnam, I wonder if this is either a regional form, or a Google Translate issue. In either case I don't think it merits mention on English Wikipedia. Fishsicles (talk) 14:17, 17 September 2024 (UTC)[reply]
    I'd also note that as best I can correlate the two translations, "acetoic acid" does not appear to refer to pyruvic acid, which probably pushes it more in line with a possible MTL issue. Fishsicles (talk) 14:23, 17 September 2024 (UTC)[reply]

    Chembox for a mixture?

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    I wanted to start an article on F-53B, a PFAS mixture mostly used in Asia. It currently does not have a wiki page and since it came up in my masters research (and it is often misused) I thought it would be a good way of putting my degree to use. However, F-53 is a mixture of 2 compounds, one major and one minor. How would I put this in the chembox? Do I make 2 chemboxes, one for the major and one for the minor? Did the Mixbox ever get off the ground?

    I'm still unsure if I can find enough secondary and tertiary sources to actually get the paper off the ground, but I want to hope.

    Speederzzz (Talk) (Stalk me) 13:59, 26 September 2024 (UTC)[reply]

    @Speederzzz A brief search shows this entry in Pubchem and this in Wikidata. These seem to be for F-53B, or at least one of its components. What's the other? My suggestion would be to make the article about that one material (including chembox) and if the minor component is important then place a second chembox later on for it, or just ignore that part. Chemboxes can have multiple components (e.g. see cyhalothrin) but usually only for various notable isomers; I've never seen one for separate substances. doi:10.1016/j.teac.2019.e00066 looks like good review source. Mike Turnbull (talk) 14:26, 26 September 2024 (UTC)[reply]
    Chembox can handle mixtures, with effort, but I wouldn't do so here. Industrial mixtures are prone to change. There seems to be some disagreement as to whether F-53 is a mixture or a pure product (see here) which implies that it might be either, depending on where you buy it. --Project Osprey (talk) 14:43, 26 September 2024 (UTC)[reply]
    You're right, the definitions differ (which caused me much grief during my literature studies). It's one of the struggles I've had in finding a way to formulate the page. Perhaps it would be best to focus on the traits of 6:2 and leave 8:2 for a separate section (with perhaps one mention of the very rarely occurring 10:2). Finding sources on it that aren't scientific papers sadly is still a struggle, although I expect some more attention in the future due to the EU ban that might come to a vote next year (I hope). I still gotta fully look at which sources I can and cannot use here in this corner of wikipedia, but I've had a busy real life that takes precedence. Thanks for the input!
    Speederzzz (Talk) (Stalk me) 22:45, 26 September 2024 (UTC)[reply]
    I feel your pain. It might be worth trying to figure out if it's an intentional blend of 2 or more compounds (which might be done to exploit a synergism, but those details would probably only be in the patent literature), or if it's just a reactor bottoms product (in which case it'll be a huge horrid mess of things). The latter is more common than you might expect (or wish), for instance tricresyl phosphate is effectively a mixture of up to 10 compounds. You biggest problem is that it seems to be used mostly in china, so the literature will mostly be in Chinese. There seems to be some use in the US. The situation in the EU is weird. As best as I can tell it's not ECHA registered, so it shouldn't be possible to use it, but it has been detected in places (here), so it's getting in somehow. If it's not approved in the EU already then the ban wont effect it, so you shouldn't expect any major attention I'm afraid. Project Osprey (talk) 11:22, 27 September 2024 (UTC)[reply]
    I do expect it is an unintentional mixture, seeing how there is a nice series of 6:2 - 8:2 - 10:2 of decreasing percentages that seem probably for a reaction where the one of the reactants is a 2C PFAS, however I have not yet found (and do not expect to ever find) how F53-B is made so I can't be sure. You make a good point on the EU situation, I feel I was a bit too much like this XKCD where I hoped that more attention would be given to all PFAS, but the last time I went to a talk about PFAS the non-expert host did not know the difference PFAS and PFOS. *sigh*
    Speederzzz (Talk) (Stalk me) 11:35, 27 September 2024 (UTC)[reply]
    The synthesis is nightmare fuel. Tetrafluoroethylene and sulfur trioxide react to give a sultone, which ring opens to give a sulfonate-alcohol. More reactions with tetrafluoroethylene and what looks like iodine monochloride (first time I've seen that in an industrial process) give the expected structure except with iodine at the end. The original F53 was made by radical fluorination of this with HF and antimony pentafluoride (truly awful chemistry I assure you - it will slowly chew through your PTFE reactor lining, after which it will rapidly eat through the metal). Seemingly this proved too expensive to make so they switched to F53-B where they displaced with chloride instead. The details are (here), you probably will need to download and open on your desktop so Adobe will know to install the correct character set. I can read not a word of it but the schemes are universal. It confirms low oligomers n=1-4. Project Osprey (talk) 14:06, 27 September 2024 (UTC)[reply]
    It's a shame there is still a barrier between languages for such interesting chemistry. I was suprised by this paper claiming F53 is F(CF2CF2)4OCF2CF2SO3K, being the 8:2 version (8 CF2 on one side of the O, 2 CF2 on the other side). I do remember reading about the fact they used the chlorinated version because of the difference in cost (and seemingly as a loophole in the PFOS ban, since it's almost just as harmful as PFAS).
    Speederzzz (Talk) (Stalk me) 14:40, 27 September 2024 (UTC)[reply]
    Google translate does an OK job. At least you know enough to write a chembox now. For an image show the core structure with appropriate brackets, use indexed parameters to show a mixture of values from the commercial mixture and the dominant isomer depending on what you've got. You know more about it than the regulators now. Project Osprey (talk) 15:02, 27 September 2024 (UTC)[reply]
    Thanks for the review, I should check over my sources from the piece I wrote for my masters on the occurrence and alternatives for PFAS. The idea to write a wiki page on F53-B came partially from my frustration from how unclear the definition of F53-B was. Speederzzz (Talk) (Stalk me) 22:47, 26 September 2024 (UTC)[reply]