Talk:Chemical element/Archive 2

Stable
The Description section states confidently "Of the 98 naturally occurring elements, those with atomic numbers 1 through 40 are all considered stable." However, as we know from the potassium article, "Traces of 40 K are found in all potassium, and is the most common radioisotope in the human body." and the product of its decay, Argon, continues to accumulate in earth's atmosphere. Carbon also has a naturally-occurring radioisotope. Some clarification is therefore needed. Plant surfer 14:27, 13 July 2015 (UTC)
 * I have now tried to improve this section. To start, I have the changed the mention of stable elements (=??) to stable isotopes (= no observed radioactive decay). Dirac66 (talk) 02:05, 14 July 2015 (UTC)


 * Dirac66: Thank you for your edits to this Page, including your edits of my edits. All are definite improvements. Regards, IiKkEe (talk) 15:36, 19 July 2015 (UTC)


 * K-40 has mass number 40 but an atomic number of 19, and is unstable only because it's an unstable isotope of an element that generally is stable only at mass numbers of 39 or 41. What the article means is that elements with atomic numbers 1 through 40 (ie hydrogen to zirconium) have at least one stable isotope that is theoretically stable, with no way to decay to anything else by some other possible process. Above 40, this isn't true, and even stable isotopes that have never been seen to decay are theoretically unstable to decay by alpha decay, spontaneous fission, double beta decay, and so on. I would have thought anything over iron and nickel (Z = 26 and 28) would be theoretically unstable to decay back toward those elements, but apparently mechanistic considerations inhibit all processes until you get to Z = 41. No, I don't have a reference. S  B Harris 23:25, 31 July 2015 (UTC)

Dark matter
The article states the existence of dark matter as a fact while its existence is yet to be proven. Sudoer86 (talk) 15:04, 16 January 2016 (UTC)
 * I have reworded the second paragraph to specify that dark matter is suggested by astronomical observations. Dirac66 (talk) 23:47, 16 January 2016 (UTC)

Semi-protected edit request on 21 June 2016
This article should be updated to reflect the recent IUPAC announcement. Following the section on Recently Discovered Elements, please add the following line.

"On 8 June 2016, IUPAC announced it is naming the four new elements Nihonium (113: Nh), Moscovium (115: Mc), Tennessine (113: Ts), and Oganesson (113: Og). These names are currently disclosed for public review and are expected to be approved by the end of 2016."

Opus Two (talk) 04:58, 21 June 2016 (UTC)
 * Yes check.svg Done — Andy W. ( talk  · ctb) 06:03, 21 June 2016 (UTC)

Semi-protected edit request on 25 June 2016
The sentence starting "Elements with greater than twenty-six protons are formed by supernova nucleosynthesis in supernovae, which, when they explode, blast these elements far into space as planetary nebulae..." contains an error. Please replace 'planetary nebulae' with 'supernova remnants'.

Lookup the two terms in Wikipedia and find that planetary nebulae result from not-too-massive stars and contain elements up to iron, while only heavier stars explode as supernovae, that leave supernova remnants containing the elements beyond iron.

The planetaries and the remnants are quite different beasts.

Teun.nijssen (talk) 19:30, 25 June 2016 (UTC)


 * Done. Thanks for noticing this error. Dirac66 (talk) 21:13, 25 June 2016 (UTC)

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Update of table image in side box
The lead-in/side box image needs to be updated to match the newly assigned names (as per the interactive table further down). 203.173.35.138 (talk) 07:54, 3 December 2016 (UTC)
 * Could you tell in which article you saw this? -DePiep (talk) 12:15, 6 December 2017 (UTC)

The order of origination
Can the order of origination of the elements be added, or referenced, as best it is known? For example I understand that hydrogen was the first element to be formed in the universe, followed by helium and then others. Certainly the order of (human-made) origination of the trans-uranium elements is known. It would certainly be interesting, and perhaps even useful, to tabulate the elements in order of their creation in the universe, along with an identification of the creation mechanism. Thanks! --Lbeaumont (talk) 18:48, 22 December 2017 (UTC)


 * Some information on this is found at Nucleosynthesis. Dirac66 (talk) 21:49, 23 December 2017 (UTC)

Sum vs. addends
In Section "Properties", Sub-Section "Occurrence and origin on Earth", there is a sentence that states: "Of these 10 transient elements, 5 (polonium, radon, radium, actinium, and protactinium) are relatively common decay products of thorium, uranium, and plutonium. The remaining 6 transient elements (technetium, promethium, astatine, francium, neptunium, and plutonium) occur only rarely, as products of rare decay modes or nuclear reaction processes involving uranium or other heavy elements". In my opinion, there should be something to be modified, since 5 + 6 ≠ 10. Or perhaps it's me that did not understand, as it often occurs?Ekisbares (talk) 10:19, 19 January 2018 (UTC)
 * Fixed. There is some doubt on whether plutonium is primordial. Burzuchius (talk) 20:02, 19 January 2018 (UTC)

"A chemical element is a species of atoms..." (The article very first words)
I've never heard of species of atoms and have no idea what other species of atoms there might be that are not chemical elements ? Since the article about atoms does not clarify what are species of atoms, I strongly suggest either to change the formulation, edit the article on atoms to add and explain the concept, or at least add that explanation to this article (chemical element), in order to shed some light on this ! Zigomar7 (talk) 18:37, 10 October 2018 (UTC)
 * Me neither, but also it does not imply "other" species of satoms exist. Try reading carefullly, and click species or species (disambiguation). -DePiep (talk) 16:42, 11 October 2018 (UTC)
 * The main point in what you say is that you haven't seen it either so it does need clarification. I disagree with your conclusion that ``it does not imply "other" species``. The wording implies that there would be, please read carefully, so the wording needs to be changed if there are not ! Disambiguation for species gives one result related to chemistry ``Chemical species, a common name for atoms, molecules, molecular fragments, ions, etc``, meaning atoms are chemical elements species, yielding nothing conclusive for species of atoms, so it is irrelevant... except for the fact that it might be "chemical species" that was meant in the first place, and not "atom species", in which case it needs to be changed accordingly.Zigomar7 (talk) 17:53, 11 October 2018 (UTC)
 * Well, that it is/was unknown to me does not mean the intro is wrong: the shortcoming could be on the reader's side. You too say you have not "heard" about it, but you cannot claim from that that it is wrong or does not exist. (TBH, I already met the "species" wording in wikidata re this topic, but did not research it).
 * Second, re my 'does not imply': intro now says "A chemical element [singular; DP] is a species of atoms". i.e. an element is one species with multiple atoms (who are of the same element btw). The "other" species of atoms you expect are the other elements. (so: chlorine is a species of atoms, and copper is an other species of atoms). IOW: next to "a species of atoms" (eg chlorine), there are 117 other species of atoms (other elements).
 * re meaning atoms are chemical elements species: allow me to correct: "meaning elements are chemical elements species": elements as substances, like chuncks you can throw, not single atom definition here. So, it does not say "atom species" and correcly not: it is a chemical species having special aspect "atoms" not compound molecules.
 * All in all: it could be clearer, with good wikilinks, but there is no error in there. -DePiep (talk) 18:52, 11 October 2018 (UTC)

Modifying the definition: a proposal
It is the same IUPAC in its Gold Book to state that a chemical element is

“A species of atoms; all atoms with the same number of protons in the atomic nucleus”.

This definition is almost identical with the one placed at the beginning of the article, namely:

"A chemical element is a species of atoms having the same number of protons in their atomic nuclei (that is, the same atomic number, or Z). For example, the atomic number of oxygen is 8, so the element oxygen consists of all atoms which have exactly 8 protons". .

Yet some people dislike, and have questioned, this definition. I too don’t like it, and I think a better one could be the following:

'A chemical element is any of the various kinds (types'') of atoms, different from each other mainly because of the different number of protons present in their nuclei, also known as atomic number, having Z as symbol. The atomic number unambiguously identifies an atom as being of a given element. For example, the atomic number of oxygen is 8, so all the atoms (and only those) having exactly 8 protons in their nuclei are said to belong to element oxygen.'''

The parts in italic within brackets can be considered as alternative to those immediately preceding them. I am not an English native speaker, so I haven’t enough feeling about which term, or verb, would be more appropriate.

If somebody else agree, I would propose to replace the beginning of the article with the one I put forward here above in bold characters.Ekisbares (talk) 15:42, 23 October 2018 (UTC)

Semi-protected edit request on 27 December 2018
Species of atom, not species of "atoms." As in, tiger is a species of cat, not a species of cats. Thisfunkyone (talk) 19:49, 27 December 2018 (UTC)
 * Yes check.svg Done DannyS712 (talk) 21:56, 27 December 2018 (UTC)

Semi-protected edit request on 11 October 2016
It seems to me that neptunium, element number 93, is a synthetic element, meaning that it does not occur naturally. I would like the number 94 (" the first 94 occur naturally on Earth ") to be corrected. One must also remember that element 43 (Technetium) and element 61 (promethium) are both synthetic elements, created by chemists in a laboratory. Therefore, there are only 90 naturally occurring elements on that table.

90.77.101.42 (talk) 17:58, 11 October 2016 (UTC)


 * Thank you for this suggestion. However, the Occurrence sections of the articles for Np, Pu, Tc and Pm indicate that trace amounts of all four have been found on Earth in uranium-bearing ores. Np and Pu are produced by radioactive decay chains of U including beta decay, while Tc and Pm are produced by natural fission of U.


 * It is true that these four elements were produced synthetically before their natural occurrences were discovered. Also, the natural quantities are so small that they are not practical sources for these elements. But since there are minute amounts on Earth, the sentence now in the article is not actually incorrect. Dirac66 (talk) 19:50, 11 October 2016 (UTC)
 * If you're imposing a threshold like that, there are only 88 natural elements. At and Fr do not occur significantly in nature either: they are so rare that you cannot really extract them from nature. Anyway, Tc and Pm come from natural spontaneous fission of U (and Pm also from natural alpha decay of Eu), At and Fr from the decay chains of U, and Np and Pu from single neutron capture and beta decay of U. Double sharp (talk) 02:46, 23 October 2016 (UTC)
 * P.S. It is likely that minuscule amounts of interstellar Cm are still being deposited on Earth, which would pass through Am during its decay, but this has not yet been found. So perhaps one day we may hear of 96 natural elements. ^_^ Double sharp (talk) 09:21, 14 February 2019 (UTC)

All are observed, but some are predicted
In case my edit summary for my revert was too cryptic, here's an explanation: All of these elements (with no exceptions) are observed to be stable. However, some of these are predicted to be radioactive with a half-life so long that it is not surprising that it radioactive decay has been observed. YBG (talk) 19:18, 18 February 2019 (UTC)
 * But your point is well-taken; I have now reworded it so that I think it is clearer. Comments? YBG (talk) 19:23, 18 February 2019 (UTC)


 * It is clearer but unfortunately not quite true yet. As stated correctly in the Description section (2nd paragraph), there are two exceptions: Tc(Z=43) and Pm(Z=61) have no stable isotopes. And their longest-lived radioisotopes have half-lives which are not that long: Tc-98 is 4.2 million years so the radioactivity is easily measurable, and Pm-145 is only 17.7 years! Dirac66 (talk) 21:08, 18 February 2019 (UTC)


 * Seen and fixed, thank you. ComplexRational (talk) 21:34, 18 February 2019 (UTC)

Melting point of helium
It says on helium page that it has a melting point of 0.95K. This page says helium has no melting point. What's up with that?? Porygon-Z 13:50, 5 April 2019 (UTC) — Preceding unsigned comment added by Porygon-Z474 (talk • contribs)
 * Helium cannot be made solid, so it cannot "melt", as it cannot freeze first. Jeb3  Talk at me here  13:53, 5 April 2019 (UTC)
 * Its because helium do not have a mp at normal pressure. The helium infobox says "(at 2.5 MPa)" which is the pressure. Actually, its is disscussed on the talk:Helium. Christian75 (talk) 13:55, 5 April 2019 (UTC)
 * OK I was confused I don't quite get it because why couldn't you put in the infobox "2.5 MPa none for STP"? Porygon-Z 01:34, 6 April 2019 (UTC) — Preceding unsigned comment added by Porygon-Z474 (talk • contribs)

Periodic table picture link
Could someone please change the picture of the periodic table to Periodic Table? The 2nd Red Guy (talk) 21:25, 15 April 2019 (UTC)
 * ✅ -DePiep (talk) 15:35, 16 April 2019 (UTC)

Thanks! The 2nd Red Guy (talk) 21:03, 16 April 2019 (UTC)

Semi-protected edit request on 12 January 2020
From- One hundred eighteen elements have been identified: the first 94 occur naturally on Earth, and the remaining 24 are synthetic elements.

To- In all, 118 elements have been identified. The first 94 elements occur naturally on Earth, while the remaining 24 are synthetic (man-made) elements. Kleio B (talk) 10:37, 12 January 2020 (UTC)
 * ✅ This change is indeed more in line with writing conventions. Thank you for bringing this up. ComplexRational (talk) 12:42, 12 January 2020 (UTC)

What is an element?
This article is missing the answer to a fundamental question of great historical interest: what, in the past, distinguished a single element from every other chemical entity? Petergans (talk) 21:05, 26 May 2020 (UTC)


 * Might be able to grab some content from History of chemistry. There are 103 mentions of the word 'element' and some discussion of an element being a substance that cannot be broken down further. --Ben (talk) 21:37, 26 May 2020 (UTC)


 * This article does now have a History section which starts from Earth, Water, Air and Fire. Dirac66 (talk) 23:46, 26 May 2020 (UTC)

Lead section of article is sprawling and confusing to non-scientists
I'm comparing this article with Cell (biology), which I feel is an article of similar importance and scope to its scientific field. The lead on Cell is concise; the first sentence avoids technical terminology and heavy blue-linking and simply states "The cell is the basic structural, functional, and biological unit of all known organisms." Meanwhile this article states "In chemistry, an element is a species of atom having the same number of protons in its atomic nuclei (that is, the same atomic number, or Z)." Which IMO, does not do such a great job at actually conveying what the concept of an element is, without the reader first needing to click through atomic nucleus / atom / proton.

Another issue raised: the third paragraph (starts with "Chemical elements constitute all of the ordinary matter of the universe...") sprawls out into a lengthy explanation of the creation of various elements which I feel would be better suited to a different part of the article.

I understand that the heavy scientific explanation is 100% necessary to the subject matter, but would it be prudent to revise and trim the lead section to provide a more "accessible overview" a la MOS:INTRO? I would love to try it myself but I think I need to gather some outside opinion since this is such a prominent page. -- Breathlessblizzard (talk) 03:52, 20 June 2020 (UTC)

Explanation of my edit:
Having not received much response here, I have decided to follow the bold/revert/discuss cycle and submit a pretty sweeping change to the lead section for consideration. I've cut some particular sections and added others, and will explain in more detail as follows. If this is not how I should be approaching this, please revert without hesitation (especially if you feel that I may be dipping into Wikipedia:BRD_misuse#Filibustering). Please read my above post for my thoughts on the original lead; my goal here was to make the lead section more accessible and less lengthy.

Major deletions

 * Removal of paragraph detailing difference between dark matter and baryonic matter; this dipped into particle physics and I felt it was not appropriate for the lead section of a foundational chemistry article
 * Removal of paragraph about the natural synthesis of elements via Big Bang, cosmic ray spallation, and supernovas; this is addressed in the literal first paragraph after the lead, and I again felt that it was not an appropriate topic to lead with
 * Removal of discussion about the fundamental meaning of "element" and its use both as a descriptor of "atoms w/ same atomic number" and "pure substance such as hydrogen gas"; I felt this was mostly addressed in my first paragraph but believe it still needs a little work
 * Removal of statement about smelting of mineral elements by primitive societies; I felt it did not match the scope of the article

Major additions

 * Reworked the first sentence to provide an accessible definition of element in both a simple english and scientific sense
 * Add mention of classical elements and alchemy as precursors to the modern understanding of elements
 * Attribute modern understanding of elements to Dmitri Mendeleev as a tie-in to the explanation of periodic table

I'm fully expecting this to be a bit of a process; thank you for reading! -- Breathlessblizzard (talk) 04:31, 21 June 2020 (UTC)


 * I think these edits are reasonable. The intro was too long, and the essential part of the deleted material seems to be found elsewhere in the article. For example the natural synthesis of the elements is an important topic which should be in the article but not really in the intro, and in fact we do have a section Origin of the elements which includes the same points, so the deletion from the intro has done no harm. Dirac66 (talk) 16:28, 26 June 2020 (UTC)

Semi-protected edit request on 19 August 2020
In the description, in the first line of paragraph three, the date, 2010, must be updated to 2020. 2601:98A:4001:C410:E44A:2EBD:71E6:8143 (talk) 21:49, 19 August 2020 (UTC)

Done  Heart  Glow (talk) 04:48, 20 August 2020 (UTC)


 * Actually 2010 referred to the date at which the 118th known element (tennessine) was discovered. So I have changed "As of 2020 there are" to "There are now", which won't have to be updated every January 1. And I have added in the next sentence that the two most recent element discoveries were in 2006 and 2010. This will only have to be updated when another new element is discovered. Dirac66 (talk) 00:22, 26 August 2020 (UTC)

Biological roles of the elements
I have prepared a table evaluating the biological role of every element. Some of this information I got from Wiki pages on each element, but I found those pages to be greatly, often exclusively, focused on human health and medical questions, so I had to delve into the literature to find evidence regarding effects in the broader biological sense (plants, bacteria, etc.). This information could be added to the individual element pages, but there are large-scale patterns in the data that warrant description as well, such as the relationship between abundance in the earth's crust and prevalence in biological systems.

So... I was wondering what to do with this. It's not quite ready for publication yet (have to polish the language and include the citations) but that will be a laborious business so I wanted to first determine where it would go and what form it would take. Currently it's in the form of a table with columns for Element, Atomic Number, Rank, Beneficial Role, and Adverse Role. "Rank" is a categorical variable defined in table notes. It seems to me that options include (a) adding biological info to the list of elements on the "Chemical Element" page; creating on new page on "biological roles of the elements"; or adding a new section to the "Chemical element" page. So, I'm looking for guidance here.

If it would help, I could post draft text somewhere; it's currently a Word file. OlyScientist (talk) 18:16, 4 April 2020 (UTC)
 * Why not start a page Draft:Biological roles of the elements? Can we help finding other pages? Sounds like an article titel that is useful. I am at home at WP:ELEMENT. -DePiep (talk) 18:25, 4 April 2020 (UTC)

Have started the draft article as suggested. Populated it with links to a variety of relevent pages. BTW I should mention that I'm a relative Wikipedia newbie and not sure about procedures. — Preceding unsigned comment added by OlyScientist (talk • contribs) 17:47, 7 April 2020 (UTC)

Completed and published draft article. Added link to "see also" section of "chemical elements." OlyScientist (talk) 13:40, 5 May 2020 (UTC)
 * A separate page may be useful. Right now the article is already quite densely filled with information. I think most people may more interested in the overview and general description; and for mroe topic discussion of biological roles, this could be linked to another article that then links in more biochemistry-related subtopics and such. 2A02:8388:1641:8380:DC5B:D810:7F56:116D (talk) 02:07, 21 November 2020 (UTC)

code error: out of place lines in the image of "Table of elements"
In the article Chemical element there is an image of the table of elements. When I opened this image and then clicked on [details] there is a section "Summary". Below its visible frame there appear four lines which are out of place: 1.created with Dia 2. edited with Inkscape 3. optimized with Scour 4. and edited with Notepad I suppose a little code error. I use Firefox on Windows 8.1. Please ping me. Steue (talk) 22:21, 9 October 2020 (UTC)
 * , . – Jonesey95 (talk) 22:49, 9 October 2020 (UTC)

code error in the "List of the 118 known chemical elements"
Chemical_element If I scroll down there appears a lot of text over other text. Please ping me. Steue (talk) 23:00, 9 October 2020 (UTC)


 * I don't see any overlapping text. Can you be more specific? Which words are overlapping? – Jonesey95 (talk) 01:23, 10 October 2020 (UTC)


 * see previous post by Jonesey95. -DePiep (talk) 19:39, 17 October 2020 (UTC)


 * Neither do I, Jonesey95, :). It seems to be fixed by now.
 * Steue (talk) 02:46, 18 October 2020 (UTC)

Improve the table listing all chemical elements
At the table https://en.wikipedia.org/wiki/Chemical_element#List_of_the_118_known_chemical_elements, may I recommend to add a date WHEN that element was discovered? This can be useful for people who want to present a short table in class/lecture, so to quickly get that information from wikipedia. It is possible to find out as-is, but it would be more convenient if the table also mentions this, perhaps even automatically obtaining it, to ease maintenance of the dataset. 2A02:8388:1641:8380:DC5B:D810:7F56:116D (talk) 02:05, 21 November 2020 (UTC)


 * See the article Timeline of chemical element discoveries. Dirac66 (talk) 16:21, 21 November 2020 (UTC)

The Halogen Category, the Group 12 Elements Becoming Transition Metals, and the Unknown Properties of Superheavy Elements
I have noticed that the category of halogens has been added to the periodic table, that zinc, cadmium, mercury, and copernicium have been changed to transition metals, and that elements with Z = 109–111 and 113–118 have been given chemical categorizations. I think having halogens is fine, as long as it is also noted that astatine is a metalloid. For the Group 12 elements, IUPAC defines transition metals as elements with or are capable of having an incomplete d subshell. Thus, according to IUPAC, these should be post-transition metals. I do not think that new discoveries have proven that the Group 12 elements are capable of oxidizing beyond 2+, but maybe I am wrong. If I am not, has Wikipedia reached some kind of consensus that they should now be considered transition metals? In addition, the elements that were previously deemed unknown in category (elements 109–118 except 112) are now given their categorizations. Unless I am wrong, I doubt that the chemical properties of these have been verified, and thus they should appear as "unknown". If given categories, they should at least be predicted categories. In particular, I am concerned about oganesson, which may not be a noble gas but instead a metal or metalloid due to relativistic effects. Classifying it as a noble gas may give readers incorrect information. Sorry if this topic has already been discussed and resolved somewhere else. --Ammonium121 (talk) 22:56, 8 December 2020 (UTC)


 * Well, I guess that since the elements are mostly grouped by block in this article, my question is indirectly resolved. --Ammonium121 (talk) 02:20, 11 March 2021 (UTC)

math
what happen to the atomic radius if the elements are positioned from top to bottom 136.158.42.232 (talk) 06:45, 31 March 2022 (UTC)


 * The atomic radius increases on moving down a column of the periodic table. See Atomic radius and Atomic radius. Dirac66 (talk) 14:45, 31 March 2022 (UTC)

Intro statement is not correct
The very first sentence says "an element is a pure substance consisting only of atoms that all have the same numbers of protons in their nuclei". This is one aspect of the IUPAC definition, but only part of the definition. From https://goldbook.iupac.org/terms/view/C01022 -
 * "1. A species of atoms; all atoms with the same number of protons in the atomic nucleus.
 * 2. A pure chemical substance composed of atoms with the same number of protons in the atomic nucleus. Sometimes this concept is called the elementary substance as distinct from the chemical element as defined under 1, but mostly the term chemical element is used for both concepts."

Treating an element as only the "pure substance" is incompatible with the statement later in the introductory paragraph "All of the baryonic matter of the universe is composed of chemical elements." - Most baryonic matter is NOT in "pure substance" form, but in compounds and/or ionized states. Later in the paragraph states "... elements occur in the Earth as compounds or mixtures" - but how could an "element occur" if it is only defined as a pure substance? There's a clear confusion caused by two different meanings for the same word. The same problem manifests throughout the article (for example the awkward statement on allotropes "Atoms of chemically pure elements may bond to each other chemically in more than one way", vs the rather clear "Isotopes are atoms of the same element ..., but having different numbers of neutrons"). I think both definitions need to be stated up front, as the concept of "element" encompasses both definitions and atoms of a particular kind in all their forms (compound, ionized, etc.). ArthurPSmith (talk) 16:13, 15 June 2022 (UTC)
 * As APS knows, over at Wikidata exactly the same discussion is going on: see d:Wikidata_talk:WikiProject_Chemistry. Whatever the outcome, WD and enwiki best should be consistent or align.
 * Incidentally-1, touches thie same topic.
 * Incidentally-2, looks like there are more variants than just allotropes: see the developing list at d:Wikidata:WikiProject Chemistry/Tools.
 * -DePiep (talk) 16:29, 15 June 2022 (UTC)
 * Was [:https://en.wikipedia.org/w/index.php?title=Chemical_element&oldid=963545483 that revision] better? Burzuchius (talk) 16:37, 15 June 2022 (UTC)
 * Yes, I think so. The second definition could be maybe mentioned as an addition to that old lede paragraph, saying "The term is also often used to refer to a pure chemical substance whose atoms all have the same proton number." Double sharp (talk) 16:46, 15 June 2022 (UTC)
 * I don't think it was "better" in all respects, but it did have a better first sentence. I don't mean to impose a Wikidata-based view of the matter here either, even though that is where this problem was pointed out to me - the question is what is a true and consistent thing to say about it. And no, this article doesn't need to wait for any outcome of a Wikidata discussion. It's clear this article as it stands adopts both meanings inconsistently. The "species of atom" definition is more encompassing, but it does not quite capture the substance side of it. Perhaps an opening definition along the lines of "There are two closely related meanings to the term chemical element, as a species of atoms, or a pure substance composed only of atoms of the same species". ? ArthurPSmith (talk) 18:12, 15 June 2022 (UTC)
 * I've adjusted the opening sentence and doubled the goldbook reference to be clear where the claim is coming from. There may be some other cleanup that would be appropriate here also - I'm not sure where the "chemically pure element" stuff is coming from for example - an element is by definition pure, so this is redundant verbiage. ArthurPSmith (talk) 20:21, 15 June 2022 (UTC)
 * Fair enough. It's just I expect the two descriptions (WD and enwiki) to have congruence, and the WD discussion at least for me is pointing out the issue. I want to understand the WD element datamodel more widely too, for future usage. This article here has improved already. -DePiep (talk) 21:54, 15 June 2022 (UTC)

Citation needed
"By November 2016, the International Union of Pure and Applied Chemistry had recognized a total of 118 elements"

Citation needed
"In chemistry, an element is a pure substance consisting only of atoms that all have the same numbers of protons in their atomic nuclei"

A chemical element is a species of atoms that have a given number of protons in their nuclei, including the pure substance consisting only of that species.[1] Unlike chemical compounds,
A chemical element is a species of atoms that have a given number of protons in their nuclei, including the pure substance consisting only of that species.[1] Unlike chemical compounds, 2405:201:5C20:F805:4973:3AE4:11BD:4555 (talk) 10:56, 20 December 2022 (UTC)