Talk:Noble metal

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"Sulfur" used in article instead of "sulphur"

I am not sure why, but presently the article uses "sulfur" despite the article being tagged "use British English". Collins and Oxford both cite "sulphur" as correct in BrE and "sulfur" as being US English. 81.96.145.214 (talk) 10:16, 25 August 2023 (UTC)[reply]

This is the standard international spelling used worldwide in chemistry and in Wikipedia chemistry articles, regardless of the variety of English in the article. See WP:SULF. --Ben (talk) 15:37, 25 August 2023 (UTC)[reply]

Apologies, I did not know about that policy. 81.96.145.214 (talk) 21:30, 25 August 2023 (UTC)[reply]

Details failing verification

Claim that physics has a different definition of noble metal to that of chemistry using Harrison 1989 as a source fails verification. No such statements appears on p520 of the paperback (or the internet library hardback which is the same). All such claims therefore deleted. Ldm1954 (talk) 00:23, 9 September 2024 (UTC)[reply]
I do not think the note given was to directly state the claim given which is why it was a note. The relevant item is whether or not physicists restrict the definition by electronic configuration. A brief search seems to indicate that this may be true. I added what I consider to be a poor reference and would prefer it if a stronger reference was found.

Unsourced and unverifiable information should not be allowed to remain. If we know something to be true, we can add it, but should note that a citation is needed as you did with your recent edit regarding all noble metals being catalytic. I think a request for citation could have been added to this claim as well, unless you know it to be false.

As an aside, with regards to your edit concerning all noble metals being catalytically active: I was going to change that to name a specific group. A good part of this article and previous discussion addresses the fact that there are varying definitions of "noble metal". I believe that you intended "noble metals" to mean the group generally recognized by chemists as being noble rather than any metal named in any source as being noble. Since you are actively reading this, I leave that to your discretion. Thank you. A15730 (talk) 01:28, 12 September 2024 (UTC)[reply]
The earlier text claimed that Pt/Pd etc were catalysts, and ignored the others which is way wrong. Ldm1954 (talk) 01:32, 12 September 2024 (UTC)[reply]

I was just removing gross errors, since my PhD thesis was on ethylene epoxidation and I have done a little on Au heterogeneous catalysts.

Separate, you have left in the footnote "n 1" which states "for instance Harrison 1989 which '''does not say that'''. Please remove the unverified claim. I did a search and could not find anything on this in contemporary literature, and have never come across such a restricted view myself. Ldm1954 (talk) 01:41, 12 September 2024 (UTC)[reply]
I think you removed the citation (Helmenstine) I've been trying to add which explicitly states: "In physics, a noble metal is one which has filled electronic d-bands. According to this definition, only gold, silver and copper are noble metals."

As I said, I think that is a poor reference, and I would like a higher quality reference, but I do think it is a valid reference. Are you indicating that you don't accept that as a reference? A15730 (talk) 01:53, 12 September 2024 (UTC)[reply]
That reference was not there, only Harrison 1989 which does not validate. If i go back to your edit in July 2024 (before i started checking) there is no such reference, and nothing back as far as Dec 2023. I checked established sources such as Kittel, Ashcroft & Mermin there is no such statement in them. Ldm1954 (talk) 02:32, 12 September 2024 (UTC)[reply]
Please see your edit done today at 01:09, 12 September ... A15730 (talk) 02:38, 12 September 2024 (UTC)[reply]
That is definitely not a source that should be used. Yes, she says that, but there is no justification in any of her sources. She is a science writer for ThoughtCo with a PhD in biomedical sciences. While one of my ex students is an executive editor of C&EN News, I would not use him as a source for facts. Ldm1954 (talk) 02:50, 12 September 2024 (UTC)[reply]
Well, she has a degree in physics (the topic at hand) and a Ph.D. in the sciences (not physics) and claims to have taught college level courses.

I also have a background in chemicals and materials and, like you, found the claim to be strange. When I searched it though, I did find a number of reputable published papers which tacitly supported the claim; papers in solid state physics discussing "the noble metals" which then were listed as Au, Ag, and Cu, or doing measurements on "the noble metals" which only included measurements on Au, Ag, and Cu. i.e. Papers that appear to have already accepted the premise that the noble metals are just Au, Ag, and Cu.

It is not as easy as one would expect to find certain things explicitly stated in standard references. e.g. Neither Greenwood and Earnshaw, Cotton and Wilkinson, or Wiberg give an explicit single list of noble metals as far as I am aware. That article does give an explicit statement which can be attributed to a known person who does have some credentials. Maybe she's wrong and, maybe, she just copied that from Wikipedia. I don't know. I would accept it and put a note that a better citation is desired as you did with your own change, unless you know it to be false.

I'll leave it to you at this point. If you read the above discussions, you will see that I'm not a big fan of grouping Cu too closely with Au, so it feels weird for me to be taking this side of the discussion anyways. It is quite clear, however, that there is definitely a group of people out there who consider Au, Ag, and Cu as the only noble metals.

As far as all the chemistry claims in the article (e.g. catalysis), I agree with you that much of it doesn't belong and could either be deleted or moved to articles dealing with the element. So, thank you for taking some of that up. Best Regards. A15730 (talk) 04:26, 12 September 2024 (UTC)[reply]
As a quick check, are the papers you are referring to on Au/Ag/Cu and SERS? That is her PhD topic and some would call it physics -- but it was discovered and largely developed by chemists (Richard P. Van Duyne). I just checked the PhD thesis of a joint student I had with Rick and she does say "noble metal nanoparticles". If this is what you are referring to then I can add it, properly cited, but not as physics v chemistry. Ldm1954 (talk) 05:52, 12 September 2024 (UTC)[reply]
No. I am referencing papers that I came across months ago when we (mainly sandbh) were cleaning up the periodic table and I first saw that claim. Add/delete as you see appropriate. If I get the time, I will try to follow up on this point as well. Best Regards. A15730 (talk) 10:55, 12 September 2024 (UTC)[reply]
Ok, I will do a search later. For certain the "filled d-band" concept does not work well and is no longer at the forefront of ab-inito understanding. Au is anomalously inert due to relativistic effects; Cu is not that inert. I don't favor statements such as "physicists say...chemists say.." as it is a non-NPOV boxing of science. Ldm1954 (talk) 11:45, 12 September 2024 (UTC)[reply]
I rewrote the relevant sections, removing overstatements and putting in a few key sources. A lot more work is needed. Ldm1954 (talk) 15:07, 12 September 2024 (UTC)[reply]

The articles I was alluding to were similar to these:

[1] See wording on p. III, "... detailed studies of the noble metals (Cu, Ag, Au)..."

[2] Titled "The electronic structure of the noble metals...:" but apparently gives results for just Cu, Ag, and Au.

[3] See wording in abstract, "Structural energetics of the noble metals, namely Cu, Ag, and Au..." Further in the introduction, "But for systems like the noble metals... appear due to the presence of the filled d bands... "

[4] Starting p. 831, "Our success was with the noble metals (...), Pd (..), Pt (...), ferromagnetic Ni (...) and ferromagnetic Fe (...)." This seems to suggest that they either believe Pd and Pt are separate from the noble metals or that the ferromagnetic metals are noble metals. Checking their publications on Pd and Pt, they do not refer to them as being noble metals as far as I can see (e.g. [5] ).

This is of no relevance now since you have already re-written that section, but I wanted to add it since I said I would follow up. I was going to stop by the library but have put that on hold.

I agree with what you wrote, in particular, regarding not trying to put the individual sciences in boxes. It does seem to be, however, that this line of reasoning is emanating from "the physics side" of things, which makes no sense because there is nothing here which "the chemists" do not know. I will keep an eye out for the root source of this since I find the history and development of science interesting. Otherwise, that is all for now. Thank you for the time you have spent on this. A15730 (talk) 21:41, 12 September 2024 (UTC)[reply]
Claim that (by inference) Ag, Au & Cu are not catalytically active is false; all three are important heterogeneous catalysts. Also claims that the partial sp filling in Pd for activity is invalid. Also CO chemisorption on unspecified surfaces is a very bad illustration of reactivity. This misrepresents the work of the original authors. Also removed as I appropriate.Ldm1954 (talk) 00:38, 9 September 2024 (UTC)[reply]
Claims that electron affinity of the noble metal plays a role in their use as electrodes etc in photodiodes is not verified by the sources. WP:OR removed. Ldm1954 (talk) 00:55, 9 September 2024 (UTC)[reply]

precious metals

When I was younger, I had borrowed a book on electroplating, which I believe was Electroplating of precious metals. Chemistry likes to group element by their column on the periodic table. That tends to get Cu along with Ag and Au. I used to have a home electroplating kit with Cu, Ag, and Au, again grouping them. As well as I know it, though, when the earth was forming, elements with a more stable oxide float on the molten earth, and others sink. Chemists also consider platinum group together, and maybe separate from noble metals. Gah4 (talk) 23:34, 12 September 2024 (UTC)[reply]