Wikipedia talk:WikiProject Chemicals/Archive 2020

Archive 2015

←

Archive 2018

Archive 2019

Archive 2020

Looking for somebody who has seen Dark Waters

One day ago, I undid this addition because of WP:V and WP:OR. The user logged out and reverted me and made some minor modifications. As the film is not yet running in Swiss cinemas, I can't verify the doubted claims. Is there anyone around who has seen Dark Waters (2019 film)? --Leyo 21:21, 30 January 2020 (UTC)

The scientific point is valid, perfluorooctanoic acid is toxic whereas teflon is not. The issue seems to be the presence of the acid as an impurity in Teflon, which does rather confuse things. I haven't seen the film, so I can't say if the criticism is valid in context. --Project Osprey (talk) 09:37, 31 January 2020 (UTC)

I am well informed about the case (I've seen The Devil We Know, read the NYT feature etc.) and very well about PFOA. I'm asking about the actual content of the film. It is likely that certain simplifications are made in the film, as the target audience are not chemists. This might have been done with more or less factual errors. --Leyo 10:02, 31 January 2020 (UTC)

See there →  Done --Leyo 12:46, 7 February 2020 (UTC)

TOXNET has moved

As communicated earlier this week, TOXNET has moved. Unfortunately, Wikipedia is also affected by that:

• The Hazardous Substances Data Bank does not exist anymore: Template:HSDB and all links in articles found using insource:/toxnet\.nlm\.nih\.gov/ do not work anymore.
• Since the Household Products Database is replaced by the Consumer Product Information Database, Template:HPD and the transcluding articles need to be adapted accordingly. The same will likely come true for articles found using insource:/householdproducts\.nlm\.nih\.gov/.

--Leyo 10:14, 20 December 2019 (UTC)

I have removed it from 2 of 3 articles. For Flucythrinate it is used as a reference, but HPD has no entry, and it is not in archive.org. So this needs a new reference. Question: what is the ID in the HPD template? It is not the CASNo. (To avoid this lack of knowledge I substed the HPD template and then changed the url to a working one). Graeme Bartlett (talk) 21:29, 20 December 2019 (UTC)

The ID in the HPD was just a number. The IDs in the new Consumer Product Information Database may be found on https://www.whatsinproducts.com/chemicals/. --Leyo 23:38, 20 December 2019 (UTC)

Template:HPD is currently used in 33 articles. --Leyo 12:50, 7 February 2020 (UTC)

Requesting article review

Hi. I have been updating and expanding articles on pesticides where I have the knowledge to do so. Before I continue this, I'd like some feedback about the ones I've already done. The more important of these are for azoxystrobin, cyhalothrin, diquat and tefluthrin. Comments welcome here or on my talk page and if you re-rate the article as well, so much the better. Michael D. Turnbull (talk) 11:27, 17 February 2020 (UTC)

One small point: if you can make your images in .svg format, then they can be better scaled, edited or converted to other languages. Graeme Bartlett (talk) 00:34, 18 February 2020 (UTC)

I've used the MDL chemistry editor since the 1980s, and am currently using Biovia Draw, as Dassault Systèmes now own the software but still make it freely available to individuals. It can't export .svg files, only its own .skc files or .bmp renderings. I've been converting these to .png using MS Paint but would be happy to convert them to .svg if you can suggest free software to do that. Michael D. Turnbull (talk) 12:21, 18 February 2020 (UTC)

Here are some further views, although the sections I selected may not be yours, but maybe the ensuing debate might be good for us all:

• "By 1974, a team of Rothamsted Research scientists had discovered three pyrethroids suitable for use in agriculture, namely permethrin, cypermethrin and deltamethrin.[8] These compounds were subsequently licensed by the NRDC, as NRDC 143, 149 and 161 respectively, to companies which could then develop them for sale in defined territories. Imperial Chemical Industries (ICI) obtained licenses to permethrin and cypermethrin but their agreement with the NRDC did not allow worldwide sales. Also, it was clear to ICI's own researchers at Jealott's Hill that future competition in the marketplace might be difficult owing to the greater potency of deltamethrin compared to the other compounds. For that reason, in the period 1974–1977, chemists there sought patentable analogues which might have advantages compared to the Rothamsted insecticides by having wider spectrum or greater cost-benefit . The first breakthrough was made when a trifluoromethyl group was used to replace one of the chlorines in cypermethrin, especially when the double bond was in its Z form. The resulting material was found to be more potent than cypermethrin, to which it is most closely related, but also with good activity against the spider mite Tetranychus urticae, which added to its attractiveness as a potential new product."

Wikipedia is a sober, encyclopedia, not a blog or around the fireplace story telling.

Why shouldn't Wikipedia explain some of the commercial thinking as to why new products were invented? Provided the information is an accurate account of what happened I think this helps what might otherwise just be dull science be turned into something of interest to readers. Michael D. Turnbull (talk) 12:21, 18 February 2020 (UTC)

And what in heck is this: "The first, and still main, use of λ-cyhalothrin is to control the larvae of Lepidopteran pests on crops such as cotton and cereals. The advantage to the farmer comes in the form of improved yield at harvest. Farmers can act in their best economic interest: the value of the additional yield can be estimated and the total cost of using the insecticide informs the decision to purchase. This cost-benefit analysis by the end user sets a maximum price which the supplier can demand and in practice pesticide prices fluctuate according to the current market value of the crops in which they are used." Are aiming to explain how farmers make decisions? I struck out the part that seems like overstepping.

I've seen on talk pages of other pesticide articles comments to the effect "why doesn't the article discus the reason anyone would use a pesticide". Farmers are not aiming to make pesticide companies rich: they are acting in their OWN economic interests. The sentence you want to strike out makes this point and shows why pesticides are different to drugs. The latter can command much larger prices than pesticides because some people will pay almost anything to get well. Michael D. Turnbull (talk) 12:21, 18 February 2020 (UTC)

• somewhere between obvious, useless, and pretentious: "All pesticides are required to seek registration from appropriate authorities in the country in which they will be used.[19]" Why is this being stated?

Because it's true? The anti-pesticide lobby may try to convince the pubic that pesticides are like software: that anyone can introduce anything they like. That's not the case: pesticides have to be approved and are continuously monitored by relevant authorities, which is discussed further in the article. I know that articles on pesticide regulation are also available but I wanted to give a brief comment to make this article stand alone for the reader. Michael D. Turnbull (talk)

Having laid all those accusations, I plead guilty to comparable sins.--Smokefoot (talk) 01:04, 18 February 2020 (UTC)

• My next point is in the synthesis sections, completely describe the process in words without dependency on the image. This increases accessibility, and usefulness for other use of the text. I added some more ids and hazards info—but that is not a complaint, as I do it for a very large number of chemical articles. I would prefer you to use Hazards_ref, or similar notes or reference attributes in the infobox, rather than sticking the reference on the value, as that will make the information more structured and useful for automated processes. Graeme Bartlett (talk) 01:59, 18 February 2020 (UTC)

This is a tough one. Using words (i.e. naming all the chemicals in the process) seems to me likely to put off general readers, not make articles more accessible. However, I grant that non-chemists won't necessarily understand the drawings either! As to Hazards_ref, I'm fine about keeping the references separate from the values: I've just been copying what I saw in some other chemboxes. Thanks for all the comments, Graeme.  Done redid the chemboxes Michael D. Turnbull (talk) 13:02, 18 February 2020 (UTC)

• Firstly, thanks for doing this. Pesticides are an important class of compounds and the attentions of someone with first hand experience (which you appear to be) are both rare and valuable. Regarding feedback, I would to some extend echo comments by others. The synthesis section would benefit from some written description but the images are really the biggest problem; we try not to include text (other than standard chemical abbreviations) so that the images can be used on foreign language pages.

This image can only be used if the text in the related history section remains essentially unchanged, we try to avoid doing that as it can make future editing more difficult.--Project Osprey (talk) 13:25, 18 February 2020 (UTC)

OK, I presume by the comment that you would prefer the pictures not to have text within them and put the text into captions which others can change, whether on the original article or to put it into another article. In the case here, we probably need two images: one for the natural products (including the "wrong" structure) and one for the stilbene and azoxystrobin itself. I'll do that soon and make a few other tweaks on the synthesis section Michael D. Turnbull (talk) 18:40, 18 February 2020 (UTC)

Another idea is to put those into separate image files rather than grouped into to one file. Then use gallery to organise and caption them. There will be more possible uses then. Graeme Bartlett (talk) 22:14, 18 February 2020 (UTC)

 Done for azoxystrobin. I elected not to use gallery as the advice on Help:Gallery tag says to avoid them if there is space for the images and text to go together. Michael D. Turnbull (talk) 13:11, 19 February 2020 (UTC)

Incidentally, I found instructions on Template:Annotated image for cropping images like the one above so they can be used elsewhere without unwanted text, and new captions can be inserted. Thus

crop

part of the image above

Michael D. Turnbull (talk) 14:27, 20 February 2020 (UTC)

Renaming of chemical articles

There is a claim at Wikipedia:Administrators' noticeboard#Renaming of Chemical Articles that someone has renamed a bunch of articles. Input is needed from people here regarding whether there is a problem that needs admin attention, and what should happen to the articles. Johnuniq (talk) 04:26, 24 February 2020 (UTC)

Safety info provided by companies

For the past few weeks, I have removed several safety edits that refer to a particular company. It seemed to me that the safety comments were not particularly, and perhaps even contrived mechanism to popularize a company. But a representative from this company politely disagrees. They may see their MSDSs as a means to do good and/or publicize their presence. Anyone who wants to help formulate response is welcome to refer to my Talk page here where the conversation is being held. Maybe we can revise our Style Manual. --Smokefoot (talk) 23:10, 6 January 2020 (UTC)

I think it should be OK to have one MSDS linked from the infobox. Though it should be a suitable MSDS for the chemical and not for other mixed products, and it should disclose information, not treat it as a trade secret, and be up-to-date. Though should we let companies add this themselves rather than us picking a good one? If we don't put it in, then we leave a vacuum for others to exploit. My opinion is let there be an infobox entry added for it. But adding sections or paragraphs in articles with the company info as references is inappropriate. We have safety information aggregators like PubChem or ECHA to reference that sort of thing. Graeme Bartlett (talk) 05:32, 7 January 2020 (UTC)

In de.wikipedia, PubChem is not accepted as a reference, because the origin and the quality of the data is often unclear. ECHA on the other hand, is not only an aggregator, but e.g. also provides harmonised classifications or GHS data in registration dossiers. --Leyo 15:53, 7 January 2020 (UTC)

Just to clarify, when you say that the edits referred to a particular company, is that happening in the article text or are they using an MSDS as a reference? The former is inappropriate but the latter may be unavoidable. Ideally, any data added to a chembox should be referenced (other than name!) and for hazard data such as H&P phrases the only source is often a commercial MSDS. An accurate reference used to support relevant data should not be considered an advert even if it incudes a company name (subject to rational extremes). By analogy, you cite Ullmann's Encyclopedia a lot but I'd be hard pressed to claim that you were spamming us with adverts for Wiley. --Project Osprey (talk) 09:42, 7 January 2020 (UTC)

Just have a look at Special:CentralAuth/Rytrom to see the user's intention. --Leyo 15:53, 7 January 2020 (UTC)

Thank you everyone for your advice. Proj Osp: Indeed, I do cite Ullmann's encyclopedia a lot, hence my hesitance about being too dogmatic in this case. The take aways are:

• MSDS's are not just ok, we want them and vendors often provide them.
• At the risk of making policy, I dont think that MSDS's are a useful source of content for the "Safety section" because many of their refs do not meet WP:MEDRS standards. Also they tend to be a little hysterical as illustrated by the NaCl case https://fscimage.fishersci.com/msds/21105.htm.

The question remains, what if some company decides to tag every MSDS-less chemical article with their MSDS? --Smokefoot (talk) 21:36, 7 January 2020 (UTC)

I agree that MSDS's are normally not suitable the "Safety section", you just get the hazard statements written up as prose, which can be make anything sound terrifying.

I'm less certain what to do if a company decides to tag every MSDS-less chemical article with their MSDS. If they're using it as a reference to support values in the chembox then that should be ok (we allowed NIOSH to set and ref all of our exposure limits), if they're just adding it as an 'external link' then no, because that's not a reference. I do however share you reservations. @Leyo's suggestion about using ECHA may be a solution, if it provides harmonised classifications then we could insist on it per WP:secondary and allow commercial MSDS's only for those compounds that it doesn't list. I do see 2 problems with this:

1. It would require us to eventually re-reference the hazard data on all of our compounds - not a trivial job
2. The ECHA website doesn't look easy to reference, there are lots of nested i-frames and collapsed tables. If we were going to reference it en masse then we might benefit from a custom template a bit like Template:Sigma-Aldrich

After a while it becomes a question of how much effort we want to spend on this. --Project Osprey (talk) 10:11, 8 January 2020 (UTC)

There are several templates referring to ECHA in de.wikipedia: The relevant ones for the purpose discussed above are:

• de:Vorlage:CLH-ECHA (specific to harmonised classifications)
• de:Vorlage:CL Inventory (C&L Inventory)
• de:Vorlage:Registrierungsdossier (registration dossiers; they contain a GHS section)

There is a table of harmonised entries in Annex VI to CLP (Excel file). This table has been used to include harmonised classifications to all affected de.wikipedia articles. However, for substances belonging to a particular group of substances that has a harmonised classification, it may not be complete. --Leyo 13:12, 8 January 2020 (UTC)

When PubChem fails to have results then I have been using ECHA. However it has the disadvantage of no PPHRASES. I have also noticed that de.wikipedia has included some invalid H phrases, so now I know where they come from. These are not (M)SDS though. The MSDS will often be more usable, with more descriptive text and relevant information. Graeme Bartlett (talk) 10:43, 10 January 2020 (UTC)

There are actually P-phrases in registration dossiers at the ECHA website. IMHO H-phrases are much more relevant for Wikipedia articles than P-phrases anyway.

Which invalid H-phrases are you talking about? Are you referring to the ones that have been deleted in the CLP Regulation? The labelling information is being updated as soon as an SDS with an up-to-date information becomes available. --Leyo 08:53, 16 January 2020 (UTC)

• If the hazard data on de.wikipedia is better than ours can we use it (presumably via wikidata) to auto-populate our chemboxes? --Project Osprey (talk) 12:01, 16 January 2020 (UTC)

• The hazard data is not on Wikidata. Anyway it will vary a lot with the product labelled. It will depend on the quantity, and form. An interesting one I saw was aluminium phosphate, corrosive when molten. Nearly all chemicals are irritating to the eye, and not good to inhale. But that does not mean that we really have to indicate that. In any case I am converting the DSD data containing pages to GHS at several per day. So far I am up to "bis" in the alphabet. I will let you know if I find more invalid valued on de.wikipedia. But since it is my third choice of source, (as its an unreliable source) I do not look there much. Graeme Bartlett (talk) 12:19, 16 January 2020 (UTC)

As opposed to here, the GHS data in de.wikipedia chemboxes is always referenced. Hence, not de.wikipedia is the source but the original reference there is. --Leyo 14:27, 16 January 2020 (UTC)

OK here is a problem: P310 is a response that should have been prefixed by an xxx+ but stands alone in de:Tantal(V)-ethoxid. Also 305+351+338​ does not work on English wikipedia, it is in the list, so I don't know why it fails. It must be some kind of template error. see pphrases for Tantalum(V) ethoxide. Graeme Bartlett (talk) 11:01, 17 January 2020 (UTC)

P310 is correct according to GESTIS.

The combination 305+351+338 would need to be added to Template:P-phrases/text to avoid the error. --Leyo 15:33, 17 January 2020 (UTC)

305+351+338 is already there though. So why isn't it working? Graeme Bartlett (talk) 00:08, 18 January 2020 (UTC)

Therefore. --Leyo 00:16, 19 January 2020 (UTC)

Thanks, now I see zero width space elimination! Graeme Bartlett (talk) 03:22, 20 January 2020 (UTC)

On a related topic recently I have seen "EPA Safer Chemical" appearing on PubChem with a green circle or yellow triangle logo. Should we include that symbol in our hazards box? I am considering how to do an AWB run to add references to the hazards in en.wikipedia. Graeme Bartlett (talk) 22:45, 16 January 2020 (UTC)

Using MSDS is a very bad idea: all MSDS are not related to pure product (MSDS composition doesn't require to mention chemical below 1%). So impurities can affect some properties. Then for solid, particles sizes can change the effect. Mentioning MSDS will require to provide some information about the grade of the chemical or other characteristics related to the form. ECHA is currently the only standardization of safeyt data and should be preferred. Snipre (talk) 21:03, 3 March 2020 (UTC)

CAS number link

Hey, we currently using https://www.commonchemistry.org for CAS number identifiers in chembox but issue with that is that it is not up-to-date (see Sodium bismuthate). Wikidata for the same uses https://chem.nlm.nih.gov which seem to have most updated info and Wikidata also says commonchemistry.org is third party database (see this). So should we use https://chem.nlm.nih.gov and if yes can someone update it at {{Chembox CASNo/format}}? ‐‐1997kB (talk) 15:08, 7 March 2020 (UTC)

Palladium on carbon vs Palladium black

Palladium on carbon and Palladium black have the same chembox (including CAS). Should they be merged? Or are they genuinely different things? --Project Osprey (talk) 09:04, 3 April 2020 (UTC)

My strong impression is that they are quite distinct materials: Pd/C is a popular supported catalyst, Pd black, like Pt black is a material with the composition PdO_x. --Smokefoot (talk) 12:45, 3 April 2020 (UTC)

They bear the same relationship as Platinum on carbon and Platinum black (see DOI:10.1595/147106707X176210). That is, they are different samples forms of metallic palladium used in different ways in catalysis. I think they have all been given the same CAS (and e.g. Inchi / Smiles) as these are just the one for elemental Palladium. The synthesis of the Pd or Pt black is from the oxides, typically, but the substances themselves are the metal after reduction. Whether they get merged (possibly even with the article on Palladium) is a matter of debate: personally I'd leave them separate, with "see also" references. That's what the articles currently have. Michael D. Turnbull (talk) 17:28, 3 April 2020 (UTC)

I guess they could be called different "sample forms" if "sample form" means one is 5% Pd by weight and the other is mainly Pd by weight. People use 5% Pd/C routinely for hydrogenations and hydrogenolysis. The prep in OS uses 95% by weight Norite, The diff is alluded to here: DOI:10.15227/orgsyn.026.0077. Pt black is ill-defined material popularized by Roger Adams. Mainly Pt with OH in it. DOI:10.15227/orgsyn.008.0092. Sample forms? What is a sample form? --Smokefoot (talk) 19:39, 3 April 2020 (UTC)

Sorry, I use "sample form" as an expression from my past employment when I spent many hours trying to educate colleagues on the difference between a chemical substance and a chemical sample. We made new active ingredients (substances) and tested them for properties of interest. The sample made would initially be, say, a crystalline solid but by the time it was tested it might have been stored as a solution in DMSO (one sample form) or formulated with surfactants then added to water (another sample form) or, perhaps just dissolved in water (yet another sample form). All these forms contain the same substance at various concentrations: whether the difference is important or not depends on the context. For metallic Pd, it certainly matters which form of a sample you take when you want to use it as a catalyst. A lump of the metal won't work. Hence you acquire 5% Pd/C for hydrogenation reactions and perhaps use palladium black for some other purpose. I believe that it's reasonable for Wikipedia to have separate articles for Pd, Pd on C and Pd black because their properties and hence uses are so different depending on the form used, even though the "active ingredient" is just Pd. Michael D. Turnbull (talk) 15:05, 4 April 2020 (UTC)

Why are beta hydroxy acids a sub-category of aldols?

Aldols and the Category:Aldols are defined as "compounds with a hydroxyl group and a ketone (or aldehyde) oxygen separated by three carbon atoms that are single-bonded to each other". My question is why Beta hydroxy acids such as citric acid and mevalonic acid have been placed as a sub-category of Category:Aldols. None of the 29 compounds listed as being Category:Beta hydroxy acids have an aldehyde or ketone oxygen atom, only an acid carbonyl group. I don't know the correct way to fix this. Michael D. Turnbull (talk) 13:48, 9 April 2020 (UTC)

Fixed. Activating HotCat (Preferences > Gadgets) might make it easier for you to make such edits yourself in future. Our Categories are quite hit and miss. Occasionally someone tires to sort them out but it's a massive job, I'm not even sure 1 person could do it all now. --Project Osprey (talk) 21:20, 9 April 2020 (UTC)

Chemical stub generator from e.g. PubChem?

I recently had occasion to create an article on a gene, and I found this nice tool where you just put in the Gene ID from NCBI and it automatically fills in this nice stub wikicode for you, which you can copy and paste into the new article.

I wonder if there's a similar generator for chemicals, to fill out the chembox for me automatically? So I would just point it at https://pubchem.ncbi.nlm.nih.gov/compound/Allyl-phenylacetate for example, and it would generate wikicode containing the formula, synonyms, molecular weight, SMILES, and all that fun stuff. Does such a tool exist? (If not... would it make sense for me to create one??) —Keenan Pepper 20:28, 19 April 2020 (UTC)

I have this partially on User:Graeme Bartlett/monobook.js in the part near the bottom labelled "chemboxformat". To use it I copy a selection of the identifiers to the edit box, highlight it and click the link that appears on my screen labelled chemboxformat, and it converts to wikitext. Only in alpha, it is not ready to be released as a tool for general use, but you are welcome to use it. I find that synonyms need a lot of manual curation and are not worth copying from PubChem as a whole. Graeme Bartlett (talk) 22:16, 19 April 2020 (UTC)

@Keenan Pepper: Hi, can you provide a link towards the tool or the code of the tool ? Thanks. Snipre (talk) 08:20, 20 April 2020 (UTC)

Are you thinking about {{Infobox_gene}}? As far as I know this uses wikidata as a source. And this data seems to be populated by ProteinBoxBot. Note that PubChem also has an API to retrieve info. I have tried to use this API to canonicalize the SMILES. But it fails on complex ones. Graeme Bartlett (talk) 07:23, 21 April 2020 (UTC)

Sodium bisulfite is a nonexistent compound

News to me that sodium bisulfite is nonexistent. Several sources (J Chem Ed, Greenwood and Earnshaw, and Ullmann's) confirm this fact. Apparently, attempts to crystallize this salt yields sodium disulfite (Na₂S₂O₅) , aka sodium metabisulfite. But the inconvenient fact is that something called sodium bisulfite is used extensively, and it is non-identical to sodium metabisulfite. So I am trying to figure out what to say it is. Organic Synthesis is usually careful about the provenance of their reagents but they dont help in this case. Aldrich gives a hint by indicating the %SO2 in their sodium bisulfite. I guess that sodium bisulfite is some ill-defined material that dissolves to give bisulfite, for use in wine-preservation, organic synthesis, and etc.--Smokefoot (talk) 01:17, 13 March 2020 (UTC)

Well, that is a very unexpected development. Using Greenwood and Earnshaw (2nd ed., pg 717-720) as a ref: Sodium sulfite is real both in solution and solid state but sodium bisulfite is known only in solution, concentrating said solutions results in the following equilibria:

2 HSO₃⁻ ⇌ H₂O + S₂O₅²⁻

Hence the aqeous chemistry of sodium metabisulfite and sodium bisulfite should be identical (if prepared from the normal lab chemicals). I note that we report very different solubilities for those 2 compounds. Some bisulfites with large counter ions are known in the solid state doi:10.1016/0022-1902(71)80558-4, I'm not sure how that applies to the K⁺ and Ca⁺ salts. --Project Osprey (talk) 10:20, 13 March 2020 (UTC)

Interestingly, if you go the other way, the lithium salts are essentially unreported - even in solution. Lithium bisulfite only appears as a Marklush description in patents, lithium sulfite is mentioned as a boundary compound in lithium​/sulfur dioxide batteries but dismissively and without real study. You should make some and call it Smokefoot's salt. --Project Osprey (talk) 13:14, 13 March 2020 (UTC)

One Russian literature mentioned the preparation of sodium bisulfite in the solid state according to SciFinder. But I didn't find the original page of this literature. (Efremov, N. N.; Yakimetz, E. M. How to obtain sodium bisulfite in the solid state. Zhurnal Khimicheskoi Promyshlennosti (1930). Vol. 7. Pages 1224-1233. CODEN: ZHKPAD. ISSN: 0372-896X.) --Leiem (talk) 02:45, 27 April 2020 (UTC)

Sad news re Ronhjones

Just in case anyone hasn't heard, Ronhjones passed away last April in a house fire with his wife. I posted this to Wikipedia talk:WikiProject Chemistry but am also posting it here because he made several edits to this page too. Graham87 14:52, 8 May 2020 (UTC)

{{Chembox}} use-case and tracking-cat

Not sure if here or the template's talkpage is the best place to discuss an improvement of the infobox, but anyway, please visit Template talk:Chembox#Field to indicate only partial infobox if this sort of thing is of interest to you. DMacks (talk) 04:02, 4 June 2020 (UTC)

Images of samples: remove them all vs Assume good faith

Since many of us have lots of time at home, here is an interesting policy issue: Check out [edit] with this edit summary "picture of white crystals cannot be verified a being of a particular chemical compound". Well, pehaps all images of samples should be blanked out since it is difficult or impossible to establish the identity of the sample shown. At the other extreme, we have AGF, i.e. we trust images. Somewhere between these extremes, some samples have distinctive morphologies, refractive indices, or colors that would give some clues. My vote is AGF and assume that readers dont trust Wikipedia too much? (confession: I have uploaded a lot of sample images). --Smokefoot (talk) 01:44, 2 April 2020 (UTC)

Sample of Ethylenediaminetetraacetic acid disodium salt

I agree that the image (added here so readers don't need to check the EDTA page, where it has now been removed) can't be verified as any particular white solid, especially as in this case the vial isn't even labelled, which is terrible practice for a chemical! However, I don't think the issue is one of AGF, rather of "why does this article need any picture of the chemical?" The chembox for EDTA doesn't have a citation reference for any of the properties listed, including the "colourless crystals" property. I think I would prefer editors to focus on adding such references, rather than uploading unhelpful pictures. I think that most people know what "colourless crystals" mean without needing a picture. Michael D. Turnbull (talk) 13:35, 2 April 2020 (UTC)

Excellent question and one to which most experimental chemists can rapidly respond! White solids often look distinctive to us: some are milky white (sodium thiosulfate), some are glistening plates (anthracene), some are chunky (NaCl), etc. Of course all or most can be pulverized to appear similar. Beyond white/colorless solids/liquids, we are also discussing colored materials. Who is to say that our image of sodium dichromate is legit?--Smokefoot (talk) 13:50, 2 April 2020 (UTC)

Sodium chloride - crystals

I don't think that experimental chemists are our target audience for most articles. One file for NaCl as I've just added here from Commons would be very appropriate in an article commenting on mineral forms of rock salt but hopeless if discussing table salt. Sample images are too diverse in general to be useful without comment, and preferably verifiability. Thus I would deprecate the image of sodium dichromate not because it is incorrect (I recognise it as being close to what I have used in the past in the lab) but because it isn't properly referenced, has no label in the image and is "own work". In fact, none of the images of sodium dichromate on Commons meet my idea of ideal for an encyclopedia. Better perhaps to use pictures of compounds photographed alongside bottles and MSDS from legitimate lab suppliers, for example. Michael D. Turnbull (talk) 15:37, 2 April 2020 (UTC)

Incidentally, your image of anthracene is better because the bottle is at least labelled but it's hard to find by search in Commons because you didn't put a space between "anthracene" and "in bottle", so typing the word "anthracene" into the search box there doesn't give it as a hit. Michael D. Turnbull (talk) 15:59, 2 April 2020 (UTC)

Commons is often best-searched using categories (commons:Category:Anthracene has it), which avoids spelling (typos and different languages), spacing, punctuation, and shorthand variations. Links to them are often in the sidebar and/or in boxes towards the end of WP articles as well. We (speaking as a commons editor) would love help improving the specificity of some large-and-generic cats or adding cats to images that are not well-tagged at all...feel free to ask me for assistance. DMacks (talk) 02:38, 3 April 2020 (UTC)

Pictures certainly have use in certain cases. Colour changing hydrates like copper(II) chloride for instance. --Project Osprey (talk) 17:21, 2 April 2020 (UTC)

Yes, certainly, and the article on copper(II) chloride is a good use of images to clarify the text. Going back to the case of EDTA, which was the original example, another reason to dislike the suggested (now deleted) image is that it was of the sodium salt, which is not the topic of the article. If I were reading an article on acetic acid, I don't think I'd expect a picture of a sodium acetate sample in the Chembox. In fact, acetic acid uses a picture I approve of, with a clear label of "glacial acetic acid" and looking like an unopened bottle from a reputable supplier. Michael D. Turnbull (talk) 13:11, 3 April 2020 (UTC)

Let's not stray from the intended topic: are pictures of compounds useful even if their provenance cannot be established?

• I say that the images of white and colorless compounds should be retained ordinarily, because such images can be informative because they often reveal distinctive features (example of anthracene). On the flip-side, these images do no harm.
• I vote strongly for regaining images of colored species since the eye is so good at discerning colors.

--Smokefoot (talk) 15:55, 3 April 2020 (UTC)

I agree with Smokefoot on this. That we should retain the images. They do indicate other information too, such as a likely size of a container for the substance. And it is better to have a picture than none at all. But we should use the best images, so certainly the ones that are of the substance in the article, and even better if we can be sure it really is the substance. I am also thinking that a much more magnified view of a few crystals will be useful as well. For a featured article we would want to be sure that the image was genuine and accurate. Own work does not prevent that. But photographing commercial pagages of the product may be a copyright infringement of the label. Graeme Bartlett (talk) 04:13, 7 April 2020 (UTC)

While writing another article, I came across the pages for glutamine and glutamic acid. Take a look: they have sample pictures in the Chembox essentially identical to the one we were discussing. Even if they are genuine (for which which AGF) they are not particularly helpful. I don't think that copyright comes into play for a picture of a bottle + proper label and many such images are already in use. Michael D. Turnbull (talk) 10:34, 22 April 2020 (UTC)

To me, the pictures of samples are helpful, so I hope that we can retain them. The samples of glutamine and glutamic acid look different and they differ from the edta picture we discussed earlier. Here is another angle: how do the pictures hurt? Is Wikipedia running short of memory? They are consistent with the description of the compound. If we thought that the images mislead, we would remove them, of course.--Smokefoot (talk) 10:52, 22 April 2020 (UTC)

I seem to remember this discussion having happened before, so when a conclusion has been reached perhaps you could update Wikipedia:Manual of Style/Chemistry? --Project Osprey (talk) 11:01, 22 April 2020 (UTC)

I couldn't find the earlier discussion when searching the archive but I'd like to make a proposal, thus -

The use of sample images within chemboxes is encouraged, especially where the sample illustrates a distinct color or crystal form. All images must follow the image use policy, be uploaded to Wikimedia Commons, and be of the chemical subject of the article. Pictures of chemical samples differ in quality: meeting standards of verifiability and having a scale reference appropriate for the quantity of the material shown. Example of excellent, good and poor images are given in the gallery below.

• 
  Methylcobalamin: label provides verifiability; sample amount on bottle, watch glass and flask give additional scale reference
• 
  Acetic acid: label provides verifiability and bottle gives scale reference
• 
  Anthracene crystals: label aids verifiabilty assuming good faith and container gives some scale
• 
  Sample of EDTA disodium salt but poorly verifiable (without even a label on bottle) and inappropriate in a chembox for the acid EDTA

Where multiple images of the same material exist, preference should be given to these quality considerations.

I suggest Smokefoot places this or a minor variant perhaps with more examples into Wikipedia:Manual of Style/Chemistry, if happy this answers the original question. Michael D. Turnbull (talk) 15:15, 26 April 2020 (UTC)

Minor tweak: "All images must follow the image use policy and be of the chemical subject of the article, and should be uploaded to Wikimedia Commons whenever licensing allows." That lists the three ideas in order of importance. My concern was that I don't think it should be required to be on commons, and (wearing my admin hat) sometimes it not even allowed to be there (this is part of of IUP) but still be a really good image for the article. DMacks (talk) 15:29, 26 April 2020 (UTC)

Regarding the first image (a "good" example), obviously the bottle has the amount that it contained when it was new, but we have no way of knowing that that whole "sample amount on bottle" is what is on the watchglass, and obviously we don't know the solution concentration (a value that can totally change the apparent visual color). As a further example, if I have a 1-kg container of of carbon black, I think accompaying it with a picture of 1 kg of the black powder is probably harder to see the particle nature than just a small pile. DMacks (talk) 20:57, 26 April 2020 (UTC)

OK, I put the images into our MOS and added some slightly awkward wording. Edits are of course encouraged or welcome. Check out Wikipedia:Manual of Style/Chemistry#Sample images--Smokefoot (talk) 23:34, 26 April 2020 (UTC)

Label with chemical name only is not necessary since everyone can print it at home. I prefer AGF. Some information could be provided in the file page, such as chemical source, purity, weight of the sample, etc. --Leiem (talk) 02:28, 27 April 2020 (UTC)

Just for reference, Category:Chemical pages containing a local image tracks articles whose chembox has a local (non-Commons) image. DMacks (talk) 07:58, 30 April 2020 (UTC)

Pictures of chemicals are good, in my opinion. Part of the reason so many people hate chemistry is because they think it's just boring math and lines and symbols, not realizing that these are real chemicals that come in bottles. Even though almost everything in organic chemistry is either a colorless liquid or a white solid, they ought to have pictures still. MDaxo (talk) 08:58, 27 June 2020 (UTC)

Catal's reagent#Preparation

What you do think about this cookbook-like section? --Leyo 19:30, 28 June 2020 (UTC) BTW: The chembox is missing, too.

Inappropriate. A suitable statement would be the chemical equation and words identifying the reagents and any special conditions. DMacks (talk) 23:15, 28 June 2020 (UTC)

The whole article seems to be COI. Mr Catal has very modestly named the reagent after himself, the 1st and only paper on it is currently at the pre-proof stage doi:10.1016/j.saa.2020.118631 and there's nothing to suggest that anyone other than this 1 group is using the stuff. It doesn't meet our usual standards. --Project Osprey (talk) 09:14, 29 June 2020 (UTC)

Agreed. Should now be AfD. A single reference that the referees may well not accept and certainly no secondary/tertiary sources. It's unclear to me why the article has a "See also" reference to Woollins' reagent as that is chemically completely unrelated but at least has been around for some time. Michael D. Turnbull (talk) 10:17, 29 June 2020 (UTC)

I have listed this here: Wikipedia:Articles for deletion/Catal's reagent. Please add your opinions. Graeme Bartlett (talk) 12:46, 29 June 2020 (UTC)

Please review my sources of some chemicals

Please review them and post in my talk page if i can add or not. Since it help to increase data on wikipedia i could do : Ignore_all_rules right?

Review:

https://en.wikipedia.org/wiki/Talk:5-MeO-DMT#Adding_sources

@Machinexa: you should sign your request, especially of you want people to use your talk page! Graeme Bartlett (talk) 07:41, 2 July 2020 (UTC)

Machinexa (talk) 12:42, 2 July 2020 (UTC)

Top million substances

Hello, I’m working with User:Egon Willighagen from Wikidata and others to compile a list of what we consider to be the one million most important chemicals. This list will be used to prioritize what we look at for both Wikidata and Wikipedia, and possibly other external groups that interact with us. These chemicals could include things like the elements and other basic substances you would encounter in your chemistry education, chemicals encountered in everyday life (e.g. in detergents, food additives or hair gel) as well as more niche substances such as pharmaceuticals, polymers, pollutants, biologically important materials, etc. Are there any specific collections of substances you would recommend us to look at? Please post any suggested lists or databases below. I've also posted on WT:Chemistry. Many thanks, Walkerma (talk) 18:17, 19 June 2020 (UTC)

@Walkerma: Be less subjective: take 5 of the biggest chemical databases (ChemIDplus, ChEBI, PuchChem, CHEMBL, ChemDB, NIST, ECHA,...), match their entries using an unique identifier like InChIKey or InChI, then take all chemicals present in all 5 DB, then all chemicals present in at least 4 DB, then all chemicals present in at least 3 DB, then check is you reach the million, if not continue with all chemicals present in at least 2 DB. And finally I think you will reach one million and more. If you have difficulty to reach the million (big gap betwwen a value below 1 million and value above 1 million), then add more databases and restart the process.

The only limiting step is the data extraction from databases (database ID, name and InChIKey/InChI). Good luck Snipre (talk) 19:46, 19 June 2020 (UTC)

What you describe is pretty much the approach we've taken thus far, but we wanted to take a deep dive into substance selection. There can be dangers in a simpler, automated approach, in that online databases often copy entries from one another; in the early days, for example, many erroneous entries were shared (in both directions) between ChemSpider and PubChem. This is really a "manual check" that we're not overlooking some specialist area. An analogy - if you looked at most popular movies on Amazon, Hulu, etc. you might overlook the most important movie ever made in Moldova, and you might find there is a bias towards more recent movies. I'm sure the big databases have their emphases and biases. I certainly accept your point that "most important" is going to have some subjectivity to it, but we'd rather know (about a significant database or list) than not know. Regarding the extraction, some of the Wikidata people (like Egon) are experts at data mining and validation, as I'm sure a lot of that will need to be done! Thanks, Walkerma (talk) 21:23, 19 June 2020 (UTC)

If you are looking for things in "everyday life", make sure you include anything with an E number (about 1600 substances) or in the Merck Index, the Sigma-Aldrich catalogue or the comprehensive database of pesticide common names curated at "Index of (pesticide) Inchi keys".. All these should be available to you. Another useful database (140,000 substances) should be the REACH database at "Search for chemicals". since manufacturers have in effect paid to have their compounds and data added there. I agree that it isn't a good idea simply to assume that inclusion in multiple big databases is a sign of importance: since the advent of combichem in the mid 1990s many databases became swamped with, in effect, adverts for substances that were available but pretty worthless and unlikely to make an impact on anyone. Michael D. Turnbull (talk) 12:28, 20 June 2020 (UTC)

For me, one million is not useful. The vast majority are un-notable. Core is about 1000, and then 10,000 chemicals. That's the list that interests me. We probably have the top 1000 already. Here are some additional thoughts:

• where are we now? How many chemicals do we have presently?
• complication: many of our chemical pages include multiple hydrates (inorganics) and multiple stereoisomers (R vs S as well as meso), so the list of chemical article is an under-count. (BTW: I have been pretty careful about listing various hydrates), but in general we are weak on depicting and listing both enantiomers as well as racemates. It would also be nice to have a of all chiral cmpds/ions in Wikipedia, and then make a to-do list to be sure that have both stereoisomers plus racemate for these.
• The ideal, IMHO, approach would be to extract the 10,000 most cited registry numbers from CAS. --Smokefoot (talk) 14:14, 20 June 2020 (UTC)

The idea of having the most-cited CAS numbers is a good one, if CAS would give you the data. I disagree about wanting "to be sure we have both stereoisomers plus racemate", as the vast majority of chiral products in common use are natural products where the enantiomer and the racemate are much less notable, if they have been documented at all. What are you proposing to do with the million? For sure, they won't all merit Wikipedia articles. Michael D. Turnbull (talk) 14:53, 20 June 2020 (UTC)

The million thing is Martin's idea. Diluting Wiki-Chem with lots of non-notable entries complicates searchers and floods categories, i.e. damages the functionality of the service. So one step would be to reach a consensus on our target number. The problem is that it is virtually impossible to remove articles on trivia once it appears here. So many nonchemists with vehement views show up when its time to discuss deleting an article. I imagine that CAS sees Wikipedia as a competitor, thus they would be unwilling to provide their top x,000 most cited articles.--Smokefoot (talk) 16:11, 20 June 2020 (UTC)

The million number is certainly not for Wikipedia, but it may be a useful target for Wikidata, who are also involved with this project. (Although I consider myself an inclusionist, I'm with Smokefoot on this point). With its present scope, I can't imagine Wikipedia ever growing to more than about 30,000 articles (we currently have around 20,000 articles in WP:Chemicals. Of course, as Smokefoot points out, one article might cover multiple hydrates or stereoisomers, e.g., tartaric acid, so those 20,000 articles probably represent 30-50k actual substances. But the point of the million is that although I'm soliciting help on Wikipedia, and it may impact Wikipedia a little, most of the impact will be on Wikidata, and on groups outside the Mediawiki community.

As for talking to CAS, I will certainly do that. Back in 2009, they did willingly share their "top 7,800 substances" and created CAS Common Chemistry as a result of their collaboration with us. (We were told these were the most accessed nos., but we don't know the details of exactly how they picked those substances). If you click inside Wikipedia on any CAS no. on that list, it takes you to the CAS Common Chemistry page for that substance; this was our collaborative way to validate our CAS numbers inside Wikipedia - "If you don't believe this is correct, click on the link and see what CAS says the CAS no. is!" The problem is that even CAS accepts that the list is outdated. So it would be good to talk with them; we have already spoken with people at PubChem, and they are involved too. Walkerma (talk) 17:34, 20 June 2020 (UTC)

@Walkerma: One could check all articles having {{Chembox}} (11324 P) and having {{Infobox drug}} (7044 P). These infoboxes can have multiple compounds (see Category:Chemical articles with multiple compound IDs (2,215)). -DePiep (talk) 11:18, 21 June 2020 (UTC)

Good idea. We should certainly crosscheck those lists with the 20,000 I linked above; I'm sure we'll find plenty that don't have infoboxes, and also a few that do have an infobox but no WikiProject tag. I didn't know about that multiple compound ID category! Walkerma (talk) 20:53, 21 June 2020 (UTC)

Without wanting to be drawn into a discussion about how we define 'importance', can I ask what the goal is here? If a million articles is considered unrealistic for wikipedia (and I'd agree with that) what useful output would all this data have for wikidata? --Project Osprey (talk) 18:15, 22 June 2020 (UTC)

@Project Osprey:: Wikidata is much more than just a service for Wikipedia - they already probably have at least 10x the number of substances represented than the English Wikipedia does. I think there is a huge demand for basic substance information that is machine-readable and isn't behind a paywall, and Wikidata is helping to meet that need (along with PubChem, ChemSpider, etc.) This project is partly to help guide the expansion of Wikidata, but also our interaction with outside groups & organizations. Walkerma (talk) 17:58, 24 June 2020 (UTC)

Fair enough. Probably wise to focus on obviously important compounds as chemical space is startlingly large: limiting yourself to all molecules of up to 11 atoms of C, N, O, and F (further limiting by simple valency, chemical stability etc) gives you 26 million molecules (110 million stereoisomers). Needless to say the upper limits, should any exist, are very high indeed. Data on most polymers is essentially meaningless, polypropylene for instance has a single CAS number but its forms are legion. --Project Osprey (talk) 21:18, 24 June 2020 (UTC)

Some categories of compounds that appear to be deficient in these databases are alloys, minerals, silanes, and boranes. I am assuming that CAS lists everything, but there could be whole classes of journals they miss out on indexing. Graeme Bartlett (talk) 06:15, 23 June 2020 (UTC)

@Graeme Bartlett:: Yes, I can definitely believe that. Are there any specialist databases you know of that could help us pick up more of those areas? Should we look at this list or is there something better? Walkerma (talk) 18:02, 24 June 2020 (UTC)

I don't know about databases, just when I try to look silane or borane compounds up I find them missing or in error. For minerals, the mindat web site is fairly complete, and so are the Wikipedia lists. But as a chemical I suppose we are mostly interested in the end-members or pure products. At least with minerals they distinguish between different hydrates and crystal forms. Graeme Bartlett (talk) 01:03, 25 June 2020 (UTC)

I think we can handle things like mixtures, minerals, etc. In a top 100 list, you'd expect only pure substances, but in the top million you should see minerals and alloys. Not sure how many silanes and boranes should appear, but I'll be sure to do a manual check that at least the most important ones are included. Mindat will be useful because it looks to be largely independent of the chemistry community, with the WP lists to guide us too. Thanks, Walkerma (talk) 03:26, 26 June 2020 (UTC)

Yet another class that is spottily covered in these databases is polymers. Graeme Bartlett (talk) 09:33, 29 June 2020 (UTC)

@Walkerma: WD already reaches the million of chemicals, see here, but around 10 to 20 % are mixtures. Snipre (talk) 22:04, 27 June 2020 (UTC)

And that list is without the 118 chemical elements, mind us ;-) ;-) -DePiep (talk) 00:20, 28 June 2020 (UTC)

@Walkerma:Does your current work allow you to give an up-to-date estimate for a) the total number of characterised compounds and b) the number of compounds containing carbon? I'm thinking of unique Inchi keys as I wouldn't trust a count of CAS numbers, for example. The Wikipedia article on carbon says there are "almost 10 million" compounds containing carbon but I suspect that is a large under-estimate given how many samples will exist only in pharmaceutical and agrochemical company databases: many of these will have been produced in small amounts by modern combinatorial chemistry but are genuine and well-characterised although not in the open literature. It would be nice to update the carbon article with information from a reliable source. Michael D. Turnbull (talk) 17:34, 25 July 2020 (UTC)

@Michael D. Turnbull:, I will ask your question of the group this week. That 10 million number is WAY out of date; Pubchem has over 100 million defined substances, and I'm pretty sure that number excludes prophetic substances and Markush_structures. I'll check, so we can update that article correctly. Walkerma (talk) 05:55, 27 July 2020 (UTC)

@Walkerma:Great, thanks! Thinking about it since yesterday, I realised that the answer depends on what one means by "characterised". As each person on the planet has a unique sequence of DNA, there have to be at least 7 billion such molecules alone. So, a more intelligent question might indeed be to ask how many unique Inchi keys we have, up to some molecular weight limit. You might even persuade companies to send you a complete set of their keys (excluding prophetic and wishful) so a central authority like Pubchem could maintain a global database. We know that one can't re-create the Inchi knowing just the key, so confidentiality can be maintained and Pubchem could keep the "key only" entries off their accessible database until they popped up as properly characterised substances. Michael D. Turnbull (talk) 10:41, 27 July 2020 (UTC)

BTW, I've just looked at Pubchem again and I see that they use the word "compound" to describe what I'm interested in. This is a bit weird as I'm more accustomed to using "substance" for that concept (an abstraction, a database entry associated with a unique chemical connection table). Pubchem seem to prefer to use the "substance" word to mean something more akin to what I'd call a sample record. Michael D. Turnbull (talk) 11:41, 27 July 2020 (UTC)

Inspired by this query, I have started writing List of chemical databases. There is one polymer database there. (https://polymer.nims.go.jp/PoLyInfo/) I don't think there will be any surprise entries though. Anyone is welcome to update this list. Graeme Bartlett (talk) 07:55, 31 July 2020 (UTC)

Why 1M?

Actually, I wonder what the number of "1 million" stems from, and why there is no detailing. For example, why are the first #1–100.000 exactly equally relevant as those #900.001–1.000.000? Is there no ordering at all per (say) 100.000 chemicals? Once one gathers those ID's, there could also be some ordering data with it. -DePiep (talk) 00:17, 28 June 2020 (UTC)

They're not equally relevant - water is clearly more important than number 1000 on the list, which is more important that no. 100,000. It's a steady dropoff in importance as you work down the list. One million is a number that is a workable number to begin with, and which works with the outside groups we've been talking with. For Wikidata, it could help us find where the gaps are, because I'm sure there will be some fairly important compounds missing. Thanks for sharing the information from Wikidata; that's very helpful! Walkerma (talk) 05:50, 29 June 2020 (UTC)

Ammonium nitrate

For those not following the news, there's been a large exposition in Beirut, which is currently being blamed on ammonium nitrate. These sorts of things usually result in a flurry of editing for the first few days. Extra copy-editing may be required. --Project Osprey (talk) 23:21, 4 August 2020 (UTC)

Descriptions of formulae

Any comment to descriptions like[1]. I really do not like it, and I can't see who it is written for. A chemist wouldn't care, a layman definitely would not care. I'm writing here because this is not the only article where descriptions like this are added. Christian75 (talk) 14:18, 10 August 2020 (UTC)

I agree. In that particular case the whole first paragraph is more-or-less redundant and the second paragraph is much better as a short description. Why not be WP:BOLD and just make the changes as you see fit. Most of these bad articles are going to be stub-class or start-class and of low importance, so edit away unless their talk page suggests someone has spent ages putting it into the current form, or there is a debate. Michael D. Turnbull (talk) 14:29, 10 August 2020 (UTC)

@Christian75 and Jorge Stolfi: Looking at that article again, it was edited just today to add most of the poor first paragraph, so you might want to take this up with User:Jorge Stolfi and use a talk page to discuss a better version, Michael D. Turnbull (talk) 14:40, 10 August 2020 (UTC)

Because this is not the only edit with long descriptions of molecules. This was just the recently added one. Just wanted a second opinion because nobody is rewriting these kinds of descriptions. Maybe nobody is fact-checking anything anymore. Maybe they are just fine! Christian75 (talk) 15:34, 10 August 2020 (UTC)

I also agree that the first paragraph is a poor description and that the second one is pretty good. Only missing detail I would include in the second is "consisting three six-membered rings and one five-membered ring" (rather than just "tetracyclic"). That's a better lay-description than cyclonanes. But later, in the discussion of chirality, could mention not just that it has stereocenters, but that they are at the fusion (not-presently-linked term) of each adjacent cyclohex/pentane. DMacks (talk) 15:41, 10 August 2020 (UTC)

Jorge is a purist and convinced that he knows how to explain chemistry far better than professionals do. He is an honorable but headstrong editor. Usually he edits esoterica, so I ignore it. --Smokefoot (talk) 16:09, 10 August 2020 (UTC)

I am just fighting for the non-specialist readers (like me). Specialists tend to write explanations/definitions that are understandable only by people who already know everything about the topic... --Jorge Stolfi (talk) 03:24, 11 August 2020 (UTC)

@DMacks:@Christian75: The first paragraph of an article must DEFINE the topic, not just mention some of its properties. "Define" means describe it in sufficient detail to distinguish it from anything that is not it. Just saying "three fused cycles with 6...etc" does not define gonane.
Maybe there is a better way to DEFINE that compound than the one I wrote (cycloheptadecane with bridges). Before my edit, there was already another implied description as a perhydrogenated phenanthrene with a cyclopentane attached; which is where the semi-systematic name came from. Frankly, I think that my description is simpler and more understandable, for chemists or laymen. (The "[a]" obviously tells where the cp ring goes -- but what does it mean? Would the reader have to read the gold book to find out?).

@Jorge Stolfi: Sorry for the late reply. a) "must DEFINE the topic," There is no such rule (MOS:INTRO), and you may have made it yourself. Which is quite strange since you reject all the MoS "rules". And the compound is not DEFINED because you haven't explained the absolute configuration in your definition. b) "Would the reader have to read the gold book to find out?" No the reader would look at the image (the structure of the compound). And I guess the layman (and probably the chemist too) would not care much about the specific structure, but more that it has a structure similar to steroids. No chemist would try figure out what "2(8S,9R,10S,13S,14R)-2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17-hexadecahydro-1H-cyclopenta[a]phenanthrene" means (or "cycloheptadecane (–CH2–)17 with three extra bonds connecting carbons 1 to 13, 4 to 12, and 5 to 9, replacing six hydrogen atoms."Christian75 (talk) 21:58, 13 August 2020 (UTC)

@Christian75: "There is no such rule in MOS:INTRO" Yes there is: "The lead [...] should identify the topic". And anyway that is implied in the goal of Wikipedia to be an encyclopedia (as opposed to a collection of textbooks, essays, reference manuals, etc.) The purpose of an article about X is to answer the readers' questions about X; and the first question, of course, is "what is X?".
"And the compound is not DEFINED because you haven't explained the absolute configuration in your definition." According to the article (as it was before my edit) all configurations are called "gonane", so it would in fact be incorrect to specify the configuration in the lead.
"The reader would look at the image" Definition-by-picture is not the way of Wikipedia, and I can think of several reasons why it should not be. But anyway that is not what the original lead was. It did not say "gonane is any hydrocarbon with the structure shown at right."
"I guess the layman (and probably the chemist too) would not care much about the specific structure, but more that it has a structure similar to steroids." First there was circularity there: what is a "steroid"? As I wrote below, I got to gonane, with undue difficulty, while trying to figure out the answer to that question myself. "A steroid is a derivative of gonane" seems to be a good enough definition of "steroid"; but then one cannot define "gonane" as "the parent compound of the steroids"...
All the best--Jorge Stolfi (talk) 22:35, 15 August 2020 (UTC)

@DMacks:@Christian75: PS. I got to gonane because I was trying to fix sterol, which had the same problem — it never defined what sterol was. (And I got to sterol because I was cleaning up fat, and I don't recall why I got to fat any more...) I was about to put a complicated description in sterol, but then happened to find — by external refs, not through wikilinks! — that the de-hydroxy form was "gonane". That solved the problem of sterol (which can be succinctly defined as "gonane with a hydroxyl on carbon 3") but then I had the problem of gonane in front of me...--Jorge Stolfi (talk) 05:32, 11 August 2020 (UTC)

Well this excerpt is very awkward and incorrect chemically: "Gonane is a chemical compound with formula C17H28, whose molecule can be described as three molecules of cyclohexane and one of cyclopentane, fused in a particular way." Well intentioned no doubt, but good intentions are insufficient compensation for spotty language and technical skills.--Smokefoot (talk) 15:10, 11 August 2020 (UTC)

@Smokefoot: That description is not mine, and it is not supposed to be the definition, only sort of a preparation to it. It may be enough for readers who are not interested in gonane.
Why do you say that it is inaccurate? Is it worse than "cyclopentane fused to perhydrogenated phenanthrene" (also not my description)?
The second sentence, in terms of cycloheptadecane, is the simplest way I found to accurately define the compound. (Sometimes it takes two or more sentences to write down a definition that is accurate but readable.)
If you have a better definition (even in terms of other compounds), please by all means provide it.
By the way, IUPAC has been obsessed for ages about giving names to compounds that precisely define them; and the way they view compounds like gonane is much, much weirder than "cycloheptadecane with three bridges at ...".
All the best, --Jorge Stolfi (talk) 22:35, 15 August 2020 (UTC)

Bis(2-ethylhexyl) phthalate#Production and use

I think such very high production volume chemicals would merit to have the chemical reaction shown. The same holds true for other phthalates such as diisononyl phthalate (100,000–1,000,000 t/a in the EEA). --Leyo 16:15, 8 September 2020 (UTC)

There isn't a diagram but the chemistry is shown thus

Industrial production entails the reaction of phthalic anhydride with 2-ethylhexanol:

C₆H₄(CO)₂O + 2 C₈H₁₇OH → C₆H₄(CO₂ C₈H₁₇)₂ + H₂O

That's pretty clear for a chemist and non-chemists probably wouldn't be helped by a diagram. The diisononyl phthalate article is poor in a number of ways. Michael D. Turnbull (talk) 16:34, 8 September 2020 (UTC)

Agreed we need equations for these high production chemicals. Agree also with Michael that line equations should suffice. IMHO, line equations are superior to drawings. The case of diisononyl phthalate illustrates a problem with some chemistry, i.e. heavy focus on health/safety issues, bypassiing the technology.--Smokefoot (talk) 18:50, 8 September 2020 (UTC)

de:Diisononylphthalat contains more information on production, use and properties.

I disagree with your conclusion that line equations are superior to drawings. Among others, persons with an education in natural science can read a diagram more easily than a line equation. --Leyo 09:37, 9 September 2020 (UTC)

Editors might disagree on the relative value of line eq vs drawings. In the case of diisononyl phthalate, the problem is that the nonyl groups come from mixtures, so many diastereomers exist. Thus the drawing needs to be simplified. For example, Nonylphenol shows one of many isomers simplified. Ditto for NP-40 and many other related articles (Nonoxynol-9 is probably very incorrect). Basically, the plasticizer and surfactant industry use isomeric mixtures preferentially.--Smokefoot (talk) 12:08, 9 September 2020 (UTC)

(Off topic) I know that for surfactants there's been a lot of effort to limit the isomer range, I've explained some of it at alkylbenzene sulfonates. I'm guessing that regulatory pressure accounts for most of that. I don't know what the situation is for plasticizers but I would be surprised if it wasn't similar. So it's not as bad as it could be. A lot of this dates back to WWII when they were intentionally making a lot of highly branched compounds (essentially oligomers of propylene) as high octane fuels. After the war there was much less demand so the capacity ended up getting incorporated into the newly expanding surfactants and plastics industries instead. --Project Osprey (talk) 19:28, 10 September 2020 (UTC)

Sodium phosphite on simple

I came across simple:Sodium phosphite which looks to have a wrong formula Na₃PO₃. Is that really wrong? (if so a Chemspider record also needs to be deprecated) (I think it should be Na₂HPO₃ which we call Disodium hydrogen phosphite) Should we care about what is on simple Wikipedia as it only gets about 1 view per day? But Google is presenting this as the first hit for the topic for me. Graeme Bartlett (talk) 02:45, 25 September 2020 (UTC)

Well I guess the simplest sodium phosphite is the one consisting only of sodium and phosphite ions, without any rogue H⁺'s. The formula is correct for the tri-sodium salt, which does seem to exist but has seen almost no study. Interestingly, the CAS number seems to apply to sodium phosphites in general (i.e. any amount of sodiums). Honestly though I wouldn't worry about it. --Project Osprey (talk) 20:03, 25 September 2020 (UTC)

Validation of CAS numbers; collaboration with Wikidata?

Discussion is at this subpage: /CAS_validation#Validation_of_CAS_numbers;_collaboration_with_Wikidata? and at Wikidata (Chemistry). -DePiep (talk) 12:30, 11 October 2020 (UTC)

systematic or common names for saturated carboxylic acids?

It seems we need to decide how articles for simple carboxylic acids are named, specifically whether systematic or common names are used. Presently, a mixture are used, as indicated in the table below. There have been some scattered talk page comments about this issue on individual pages, but we need to reconcile this issue in a comprehensive manner. This discussion will also have implications for the discussion above about the carboxylate pages.

Current article titles are indicated in the appropriate column.

# of carbons	Systematic name	Common name
1		formic acid
2		acetic acid
3		propionic acid
4		butyric acid
5		valeric acid
6	hexanoic acid
7	heptanoic acid
8		caprylic acid
9	nonanoic acid
10	decanoic acid
11		undecylic acid
12		lauric acid
13		tridecylic acid
14		myristic acid
15	pentadecanoic acid
16		palmitic acid
17	heptadecanoic acid
18		stearic acid

As a chemist, I assert that in this context, "common name" is a misnomer, and in most cases systematic names are more common and should instead be used per WP:COMMONNAME. The common names are in many cases historical names relating to the original natural source of the compound. Most chemists will instantly recognize the structure of the compound when they hear "octanoic acid" but only some organic chemists will know from memory what compound is meant by "caprylic acid". Propanoic acid is actually much more commonly used than the common name, propionic acid. Formic acid and acetic acid are obvious, important exceptions.

I propose that systematic names should be used for all compounds with 18 carbons or fewer, with the exceptions formic acid, acetic acid, palmitic acid, and stearic acid, the latter two being ubiquitous fatty acids that are typically described by their common names, even if non-specialists may not have memorized the carbon chain length to which they correspond. One could make a case for myristic acid and lauric acid too. Longer-chain saturated fatty acids are so uncommonly discussed that either name is obscure; it seems that the official common names are currently used for the titles of stub articles about these compounds. Note that propanoic acid was subject to a previous move discussion in 2014 located at Talk:Propionate#Requested_move_19_December_2014.

This discussion may have broader implications for other functional groups that we can tackle later with analogous discussions with similar reasoning. Either way, we at least must be consistent with the smaller acids. I am not sure how to describe consensus at Wikipedia:Manual_of_Style/Chemistry#Nomenclature, but if we reach consensus I am happy to complete the necessary moves or bring them to technical move requests if necessary. Mdewman6 (talk) 19:43, 13 September 2020 (UTC)

Thank you for raising the topic and for organizing the issue clearly. Although opposed to the proposed changes, I understand the frustration of having complicated nomenclature piled onto an intrinsically difficult topic. My arguments against the change in policy are these:

1. today: caprylic/octanoic, tomorrow: acetic/ethanoic, then: the floodgates open on the very messy nomenclature for natural products and virtually all coordination complexes. Chemistry articles are patrolled by nomeclature police, sniffing out misteps and inconsistencies (ok, a little melodramatic).
2. Here is another way to put the situation. For chemists, the least interesting component of any chemistry class is nomenclature. Similarly, the worst instructors are those most fixated on nomenclature. Instead, we editors should focus our editing energies on encyclopedic coverage of chemical concepts and knowledge. We have a lot of content that is semi-dreadful.
3. Finally, I think most articles with non-systematic titles quickly acknowledge (in the lede) the alternative systematic names, so there is no urgency.--Smokefoot (talk) 21:41, 13 September 2020 (UTC)

Your points are well-taken, though I reject the slippery slope premise, and I would never support page moves for formic acid or acetic acid. Our goal should be to have page names at the true common name, regardless of whether or not that is the "common name" in chemical nomenclature. I am not the pejorative "nomenclature police" but am indeed pointing out an inconsistency that should be dealt with somehow. I fortunately had professors who did not emphasize nomenclature (though I did find it somewhat important and interesting, like grammar in a language class) and agree that content may deserve more attention, but nevertheless we are supposed to care what is the best title for a page, regardless of redirects, and should do so in some sort of consistent way.

I could easily be persuaded that all such pages should carry the common name if that's the consensus, which I guess would be a valid interpretation of the existing chemistry MOS. I merely raise the issue here and hope to reach consensus one way or the other. I reject the premise that it's not important. Mdewman6 (talk) 22:04, 13 September 2020 (UTC)

@Mdewman6: Your proposal is, I think, equivalent to taking the preferred IUPAC name for WP articles on these compounds. They make the same exceptions for formic and acetic. Fortunately, WP has the advantage of having redirects for alternative names, which means that the issue is less urgent for us as readers can find the correct page by searching with any reasonable synonym, including the chemical formula in many cases. I would be happy to have us rename in the manner you suggest and am still waiting for a few more people to agree that it would be a good idea to merge the anions with the acids in almost all instances. Michael D. Turnbull (talk) 10:17, 14 September 2020 (UTC)

In WP:fr we use systematic names for compounds below C10 (exception acetic acid): above this limit, common names start to be shorter than systematic names. Snipre (talk) 12:44, 15 September 2020 (UTC)

Having gone through the exercise of merging articles for anions into their parent acid I have a slightly different take on this issue now. It is clear that Wikipedia's many articles on biochemistry and biology use terms like "valerate", "isovalerate", "butyrate" and so on much more frequently than "pentanoate", "3-methylbutanoate" or "butanoate". For that reason, I'm inclined to leave matters as they are now, with all our redirects in place. Thanks, @Mdewman6: for bringing this topic up. Michael D. Turnbull (talk) 11:17, 6 October 2020 (UTC)

Okay, that makes sense, though I still think we should enforce some naming consistency within a homologous set of compounds. I propose to move the outliers such as hexanoic acid, heptanoic acid, etc. to their common names, which as I said above would be consistent with the existing chemistry naming conventions and the chemistry manual of style which says to avoid systematic names. If there are no objections, I would like to proceed with these moves and will make sure all appropriate redirects are in place. And thanks @Michael D. Turnbull: for working on all those merges and to all those raising and discussing these improvements. Mdewman6 (talk) 18:36, 6 October 2020 (UTC)

Go for it.... although the definition of "homologous" is tricky, as 3-methylbutanoic could → isovaleric or → 3-methylbutyric whereas 2-methylbutanoic could → 2-methylbutyric or → alpha-butyric, if moved at all. Michael D. Turnbull (talk) 09:49, 7 October 2020 (UTC)

As an old-timer, preferring nonsystematic names (that "real" chemists actually use, ha-ha), I defer to Michael and other editors so long as net improvement is made. Thank you for the efforts and good will.--Smokefoot (talk) 18:11, 7 October 2020 (UTC)

Yeah, substitutive names quickly become the norm once you get away from straight-chain compounds, which is what I will start with for now. I'll also police the redirects and the alternative names in the infobox/lead. I'll take a look at others in the future and see where we can improve naming consistency, favoring common names where appropriate. Mdewman6 (talk) 01:05, 15 October 2020 (UTC)

Categorization by linguistic vs chemical-structure relationship

In relation to this edit, which expanded the scope of Category:Chlorimides to include [C(=O)]₂NCl rather than just =NCl, both are called "chloroimide", but one is a derivative of imide and the other is a derivative of imine. That is, they relate by name but do not seem to be analogous structures. Should they be in the same cat? Or is that a WP:DAB problem? DMacks (talk) 12:39, 13 October 2020 (UTC)

I think it might be a dab type problem. What I was originally calling chlorimides are also called chlorimines (=NCl), but most commonly seem to be called chlorimides. Analagously =NH is the imine, but [C(=O)]₂NH is the imide. Graeme Bartlett (talk) 01:02, 26 October 2020 (UTC)

What to do with Sargachromanol

This article is a two-sentence stub about a class of chemicals. There are infoboxes for three specific members of the class and the article identifies a pharmocological property of one of them. According to Pubchem, there are actually 16 members of this class (sargachromanol A–P). According to Pubchem+SciFinder, there are scattered other primary reports of bioactivity. I dislike the hybrid "class article with infobox for cherry-picked members in the lead".

I am thinking that the article should remain about the class, but not an infobox for each. Instead, maybe a gallery of them all (CASNo in captions for reference)? And then a subsection with full infobox for any individual compound that has something specific to be said. The alternative is to peel off a separate article for each specific compound and keep this as a class-only intro. I'm leaning against that latter because there is so little to say (I'm just looking for sane organization, not to do a lot of research for new content at the moment). Anyone have other ideas? DMacks (talk) 03:26, 28 October 2020 (UTC)

Looking more closely, 16 not-trivially-small structures (10.1021/np058003i) squished into a gallery might not be so legible or useful. Maybe instead a text-only table with name+CASNo? DMacks (talk) 03:41, 28 October 2020 (UTC)

@Klbrain and Gyimhu: as the still-active editors who did substantive work on it. DMacks (talk) 03:46, 28 October 2020 (UTC)

These compounds are chemically closely related to vitamin E — see article on Tocotrienol and Aldrich catalogue [2]. I'm not sure that they are worth a separate article given how little there is in the literature that's specific to them. Mike Turnbull (talk) 11:23, 28 October 2020 (UTC)

Actual wikiproject info: statistics and alerts

Article alerts

Articles for deletion 04 Nov 2024 – XW10508 (talk · edit · hist) AfDed by Toadspike (t · c) was closed as keep by Toadspike (t · c) on 06 Nov 2024; see discussion (3 participants) Categories for discussion 09 Sep 2024 – Category:Chemistry compounds navigational boxes (talk · edit · hist) CfDed by Utopes (t · c) was closed; see discussion 09 Sep 2024 – Category:Chemistry compounds templates (talk · edit · hist) CfDed by Utopes (t · c) was closed; see discussion 27 Aug 2024 – Category:Chemical compounds by type (talk · edit · hist) CfDed by Anomalous+0 (t · c) was closed; see discussion Redirects for discussion 21 Nov 2024 – 2.4-dihydroxybenzoic acid (talk · edit · hist) →2,4-Dihydroxybenzoic acid was RfDed by Mdewman6 (t · c); see discussion 21 Nov 2024 – Sontochin (talk · edit · hist) →2,4-Dihydroxybenzoic acid was RfDed by Mdewman6 (t · c); see discussion 21 Nov 2024 – SN-7619 (talk · edit · hist) →2,4-Dihydroxybenzoic acid was RfDed by Mdewman6 (t · c); see discussion Good article reassessments 24 Nov 2024 – Salt (talk · edit · hist) was nominated for GA reassessment by Boneless Pizza! (t · c); see discussion 28 Oct 2024 – Zinc oxide (talk · edit · hist) nominated for GA reassessment by Reconrabbit (t · c) was closed; see discussion 12 Oct 2024 – Mephedrone (talk · edit · hist) nominated for GA reassessment by Z1720 (t · c) was closed; see discussion Requested moves 19 Nov 2024 – Phenacylamine (talk · edit · hist) is requested to be moved to 2-Aminoacetophenone by Mdewman6 (t · c); see discussion 31 Oct 2024 – 3-Methylbutanoic acid (talk · edit · hist) move request to Isovaleric acid by Mdewman6 (t · c) was moved to Isovaleric acid (talk · edit · hist) by Andrewa (t · c) on 07 Nov 2024; see discussion Articles to be merged 11 Nov 2024 – Trifluoromethyl cation (talk · edit · hist) is proposed for merging to Trifluoromethylation by Smokefoot (t · c); see discussion 11 Nov 2024 – Cyclopentadienyl radical (talk · edit · hist) is proposed for merging to Sodium cyclopentadienide by Smokefoot (t · c); see discussion 11 Nov 2024 – Cyclopentadienyl anion (talk · edit · hist) is proposed for merging to Sodium cyclopentadienide by Smokefoot (t · c); see discussion 10 Nov 2024 – Zirconium(IV) acetate (talk · edit · hist) is proposed for merging to Zirconyl acetate by Nucleus hydro elemon (t · c); see discussion 07 Nov 2024 – Amphetamine type stimulant (talk · edit · hist) is proposed for merging to Norepinephrine–dopamine releasing agent by 76.174.0.57 (t · c); see discussion 03 Nov 2024 – Macromolecular cages (talk · edit · hist) is proposed for merging to Macromolecular assembly by Smokefoot (t · c); see discussion 20 Oct 2024 – Traneurocin (talk · edit · hist) is proposed for merging to Cyclic glycine-proline by Graeme Bartlett (t · c); see discussion 20 Oct 2024 – Carotenoid biosynthesis (talk · edit · hist) is proposed for merging to Carotenoid#Biosynthesis by Esculenta (t · c); see discussion 16 Sep 2024 – Norpropylhexedrine (talk · edit · hist) proposed for merging to Propylhexedrine by Irruptive Creditor (t · c) was closed; see discussion 16 Sep 2024 – Levopropylhexedrine (talk · edit · hist) proposed for merging to Propylhexedrine by Irruptive Creditor (t · c) was closed; see discussion (1 more...) Articles to be split 11 Oct 2024 – Alcohol (drug) (talk · edit · hist) is proposed for splitting by EducatedRedneck (t · c); see discussion 09 May 2022 – Lithium titanate (talk · edit · hist) is proposed for splitting by Nick B. (t · c); see discussion Articles for creation 22 Nov 2024 – Draft:Test4Pay (talk · edit · hist) has been submitted for AfC by Retanfeil (t · c) 03 Nov 2024 – Draft:Alcohol and society (talk · edit · hist) has been submitted for AfC by 94.255.152.53 (t · c) 20 Nov 2024 – Draft:HRAC classification (talk · edit · hist) submitted for AfC by DMacks (t · c) was accepted to HRAC classification (talk · edit · hist) by Reconrabbit (t · c) on 21 Nov 2024 13 Nov 2024 – Draft:BK-NM-AMT (talk · edit · hist) submitted for AfC by 76.174.0.57 (t · c) was moved to BK-NM-AMT (talk · edit · hist) by JJPMaster (t · c) on 14 Nov 2024 13 Nov 2024 – Draft:Lys-MDMA (talk · edit · hist) submitted for AfC by 76.174.0.57 (t · c) was accepted to Lys-MDMA (talk · edit · hist) by Graeme Bartlett (t · c) on 14 Nov 2024 13 Nov 2024 – Draft:Docarpamine (talk · edit · hist) submitted for AfC by 76.174.0.57 (t · c) was accepted to Docarpamine (talk · edit · hist) by SafariScribe (t · c) on 13 Nov 2024 01 Nov 2024 – Draft:Eicosanolide (talk · edit · hist) submitted for AfC by Aalleddem (t · c) was moved to Eicosanolide (talk · edit · hist) by Graeme Bartlett (t · c) on 02 Nov 2024 31 Oct 2024 – Draft:Octadecanolide (talk · edit · hist) submitted for AfC by Aalleddem (t · c) was moved to Octadecanolide (talk · edit · hist) by Graeme Bartlett (t · c) on 02 Nov 2024 29 Oct 2024 – Draft:FKW00GA (talk · edit · hist) submitted for AfC by 76.174.0.57 (t · c) was moved to FKW00GA (talk · edit · hist) by LR.127 (t · c) on 30 Oct 2024 28 Oct 2024 – Draft:M-MTDATA (talk · edit · hist) submitted for AfC by Asilverstream14 (t · c) was moved to M-MTDATA (talk · edit · hist) by SafariScribe (t · c) on 30 Oct 2024 (42 more...)

WPChem worklist pages by quality Quality Total FA 2 GA 16 B 172 C 76 Start 110 Stub 15 List 1 NA 3 Assessed 395 Total 395 WikiWork factors (?) ω = 1,492 Ω = 3.82

The worklist shows the actual work to be done to achieve the goals of the Chemicals wikiproject. The choice of important compounds articles to work on has been finalized in an earlier stage of the wikiproject (around mid 2005), and no further articles are added, although we remain open for strong suggestions on this talkpage. The work these days focuses on improving the articles, from Chem Stub all the way to Chem A-Class articles. The table below shows that progress.

Worklist historical status
	2005		2006		2007		2008		2009
Grade	Jun	Oct	May	Oct	Mar	Oct	Feb	Aug	Apr	Dec
A-Class	29	26	32	32	33	25	25	23	18	18
B-Class	71	84	101	130	148	156	158	180	185	188
Start	112	131	199	190	174	174	180	153	160	161
Stub	97	130	46	29	27	27	19	26	19	18
unclassified	76	-	-	-	-	-	-	-	-	-
Total	385	371	378	381	382	382	382	382	382	382
percentage ≥Chem Start	55.1	65.0	87.8	92.3	92.9	92.9	95.0	94.0	95.0	95.3
weighted progress, %	42.2	50.4	57.8	60.8	62.2	61.7	62.4	63.1	63.2	63.9

The percentage ≥ Chem Start was indicative of the initial effort. Now that we are progressing to more advanced progress, the weighted progress indicator is used, calculated as (Unclass*0 + Stub*1 + Start*2 + B-Class*3 + A-Class*4) / (Articles*4).

Chemicals articles by quality and importance Quality Importance Top High Mid Low NA ??? Total FA 1 2 2 2 7 FL 1 1 GA 1 12 22 12 47 B 21 139 325 277 12 774 C 7 74 364 1,172 26 1,643 Start 95 1,141 5,314 141 6,691 Stub 340 10,321 2 144 10,807 List 2 8 1,564 54 346 1,974 Disambig 3 30 33 Template 383 383 NA 16 161 3,546 3,723 Other 1 17 18 Assessed 30 324 2,218 18,828 4,032 669 26,101 Unassessed 1 13 163 177 Total 30 324 2,218 18,829 4,045 832 26,278 WikiWork factors (?) ω = 107,285 Ω = 5.37

Featured articles: 7 Featured lists: 1 Good articles: 47

For the statistics for all chemicals, as registered by the bot, also see complete list

Carboxylic acids vs carboxylate anion/esters

Comparison of the articles butyric acid and butyrate illustrates a problem. Both articles have hefty sections on biochemistry/biomedical/etc. Of course these sections are discussing the same species, above about pH 5, they are about butyrate anion. Solutions:

1. A lot of content could be moved from butyric acid to butyrate.
2. Merge the articles and have a section in butyric acid on "butyrates" and "butyrate esters"?

We probably could set policy on this situation. It would be useful to list those articles where the acid and the carboxylate are separate. Propionate and propionic acid are separate also.--Smokefoot (talk) 14:35, 30 August 2020 (UTC)

I would strongly support merging this type of article under the parent acid (which in these examples at least is the more complete of the pair). Esters would have to be on a case-by-case basis as there are plenty of esters that deserve a stand-alone article: for example acetyl-CoA would be ridiculous as a part of the article on acetic acid. Can we search for molecular formula in the {{chembox}} which end with (-) or @minus, which seems to be the case in the two examples you cite? Actually, these examples also give MP and BP that are in fact for their parent protonated form, so inaccurate. Michael D. Turnbull (talk) 16:06, 30 August 2020 (UTC)

We can probably all agree that we do not want duplicated content. BUT I wonder if we should not retain the separation of butyric acid and butyrate (etc), but use this distinction as an mechanism to separate out the bio-medical content. Otherwise a combined butyric acid + butyrate will be too big, I fear.--Smokefoot (talk) 17:04, 30 August 2020 (UTC)

Just for fun I created a combined article for propionic acid in my sandbox "here".. It took less than 30 minutes, since the propionate article was only a stub. I preserved its IDs in the Chembox and made no changes to improve the whole. In this case at least, I'd argue that the new version is better than either of the old ones without being too long and I'd propose putting it at Propionic acid, turning Propionate into a redirect. What do other's think? I'm not advocating this for all cases but worthwhile for some. Michael D. Turnbull (talk) 12:31, 31 August 2020 (UTC)

Very nice work. Odd-carbon acids are less "important" than evens, so I wonder if merging butyric acid and butyrate is still a good idea vs splitting off the biomed work.--Smokefoot (talk) 21:11, 31 August 2020 (UTC)

@Smokefoot, Graeme Bartlett, DMacks, and Project Osprey: Even acetate and butyrate are not that big and hexanoate, citrate and probably many others already redirect to their acids. I'd be happy to improve my sandbox for "propionic acid". and do the same for acetate + acetic acid, pentanoic acid + valerate (the latter very poor) and butyric acid + butyrate, which would be most or all that would need to be done for now. Do we have a consensus for this? Michael D. Turnbull (talk) 13:17, 2 September 2020 (UTC)

I agree with Smokefoot, that the biochemical aspects could be on a separate article, where there is enough content. The infobox for example can also be different. (Though I notice inappropriate entries in butyrate, as an ion will not have a melting point or density). Graeme Bartlett (talk) 11:46, 3 September 2020 (UTC)

I agree something has to be done. It does not make since to me that we have a separate page for butyrate but not citrate. I think in general, I support merging the two under the name for the acid except when there is sufficient content specifically on the carboxylate (or salts thereof) to justify a separate article, which probably means content of a biochemical variety. Mdewman6 (talk) 19:47, 13 September 2020 (UTC)

"Something has to be done. It does not make sense to me ..." Really? Something was done, the single greatest thing that could be done within the context of Wikipedia: great content was contributed, organized, cited, depicted. Not too shabby.

Again, this useful discussion is a convenient pause since the carboxylate vs carboxylic acid separation provides a way to break large topics into manageable articles. Butric acid simply does not occur in nature (or very rarely) whereas industry/organic synthesis have little interest in butyrate. My guess is that most of butryic acid could be in butyrate. Alternative: Butryic acid (Biochemistry).--Smokefoot (talk) 21:34, 14 September 2020 (UTC)

The point of this discussion is how to best organize that great content. My point is that it is not logical to have separate articles for buytric acid and butyrate, which is not a very important a compound as you describe, but meanwhile to have all information about citric acid on one page, including biochemical content, even though it is speciated as citrate at physiological pH. Don't we want to organize this content in a logical, consistent way? I do not understand why my comments are being construed as trivializing past efforts to add chemical content or that the naming of pages is more important than their content - both are important. Articles for each compound evolved independently, and the point of a WikiProject is to give some consistency and fill in gaps in coverage of a particular subject. Mdewman6 (talk) 23:19, 14 September 2020 (UTC)

Now  Done for propionate (i.e. this now redirects to propionic acid). This one seemed non-controversial, and I'll now move on to pentanoic acid + valerate, which I doubt anyone would object to. Please speak up if there are any among those we are discussing where you think that the biology (or other) content merits a separate article. Michael D. Turnbull (talk) 13:13, 28 September 2020 (UTC)

Also  Done for valerate and isovalerate, taking the opportunity to improve the articles for the parent acids. Now moving on to other cases where the anion articles are poor. Michael D. Turnbull (talk) 10:26, 2 October 2020 (UTC)

I have now completed the merge-and-redirect for all the acid anions I could find, except formate, acetate and butyrate. These are special cases where the article for the anion is substantially different from the one for its acid and has an important biochemical/biological flavour. There are still some minor points of contention — for example the Chembox for butyrate gives properties such as MP and BP that can only apply to the parent. Nevertheless, I would leave alone unless discussed on the talk pages of these articles before further action. As @Smokefoot: suggested, I think we should as a matter of policy say that new articles on organic acids should not create separate pages for their anions (where would we record that decision, if we have a consensus?) Michael D. Turnbull (talk) 10:59, 6 October 2020 (UTC)

Working with these pages lately in terms of other names and redirects, I do think that butyrate and butyric acid should be merged like the others. As originally proposed, an alternative is to section move the Biochemistry section and other content to butyrate, but I think this is a less desirable alternative. I support maintenance of the separate acetate and formate pages as described above. At the very least, if the butyrate page is to be kept, the infobox must be updated to remove data for the acid. It might be good to tag the pages with merge discussion banners for a week or two first pointing to this discussion. Mdewman6 (talk) 21:55, 24 October 2020 (UTC)

The merge banner idea seems reasonable to me. While the sum of the two articles is certainly bigger than in the other cases I've already done, it doesn't look too bad, given that there is some overlap we can remove. Do you Mdewman6 want to propose a draft for the post-merge, e.g. in your sandbox, or would you prefer I did that? Mike Turnbull (talk) 11:58, 25 October 2020 (UTC)

I agree the article length will be just fine, even if longer than articles for similar compounds, nothing wrong with that. I'm happy to have you do the merge, work up a draft, etc.. I'll tag the pages now; I think I'll start a new discussion at Talk:Butyric acid#Merger proposal and link to this discussion in the description, just to keep things organized and less confusing for anyone who comments on the merge specifically. Mdewman6 (talk) 19:24, 25 October 2020 (UTC)

OK, I've drafted a merged butyric acid + butyrate article in my "sandbox, here"., which will give anyone interested an idea of our proposal for the new replacement article. It won't be perfect but I suggest that it not be further edited until / if it replaces the current versions. Mike Turnbull (talk) 17:40, 27 October 2020 (UTC)

@Michael D. Turnbull: There have been no comments or opposition to the proposed merge for buytrate/butyric acid, so I think whenever you want (no rush of course) you can close that discussion with consensus to merge and complete the merger with the draft in your sandbox. Mdewman6 (talk) 21:55, 23 November 2020 (UTC)

Agreed, thanks, Mdewman6. I've completed the merger and the re-direct of Butyrate. I did do some tidying up of the content, particularly for the biochemistry sections where there was overlap, so I'd welcome some other eyes on the article Butyric acid as it stands now. It may need a bit more attention. I think we can lay this discussion to rest, with agreement that Acetate and Formate should be the only cases where anions are not merged to their parent at present. Mike Turnbull (talk) 12:38, 25 November 2020 (UTC)

Category:Articles with validated CAS Registry Numbers has been nominated for deletion

Category:Articles with validated CAS Registry Numbers, which is within the scope of this WikiProject, has been nominated for deletion. A discussion is taking place to decide whether this proposal complies with the categorization guidelines. If you would like to participate in the discussion, you are invited to add your comments at the category's entry on the categories for discussion page. Thank you. - RevelationDirect (talk) 04:00, 9 December 2020 (UTC)

If I have a question of knowledge about how a particular organic synthesis can be carried out, where shall I ask and explore on en.wiki

Hello there, per question, for example, Furan shows that furan can be made industrially from furfural? So if I want to know more about a single step -- dehydration, decarbonylation -- of a feedstock -- furfural -- and how it causes cyclization or Ring expansion (as example), where shall I ask and explore? -- Ktsquare (talk) 22:06, 27 December 2020 (UTC)

Wikipedia:Reference desk/Science might be a fair place to ask. There's a lot of interest in making things out of furfural, so a careful search of google-scholar might provide some open access sources. --Project Osprey (talk) 23:57, 27 December 2020 (UTC)

You could also ask here (or WT:CHEMISTRY). DMacks (talk) 01:17, 28 December 2020 (UTC)