Talk:Group number of lanthanides and actinides

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Talk from "Ungrouped elements" article[edit]

Just because IUPAC does not definitively place these elements in group 3, that does not mean that they should be classified as "ungrouped." The lack of definitive opinion about a grouping is not a definitive opinion about a lack of grouping. Hopefully, a good version of Group 3 elements should resolve this issue by making the reality of the ambiguity more clear. In a week or so, I will nominate this "ungrouped elements" article for deletion unless there really are peer reviewed articles out there that call the lanthanoids and actinoids "ungrouped elements" and these articles are cited by an editor. Flying Jazz 02:15, 21 January 2006 (UTC)[reply]

I created this article about 1.5 years ago, in response to the "Group (*nothing*) elements" link in articles such as Uranium etc. The "groupless" nature of those elements mentioned in this article is quite interesting and therefore this article should remain a separate one, maybe with a change in title. According to IUPAC, they aren't group 3 elements, so I think we can put a paragraph or so in the group 3 article, which links here. Deryck C. 03:38, 21 January 2006 (UTC)[reply]
I'm not 100% sure but I don't think IUPAC takes a stand either way about whether they are group 3 elements. In general, IUPAC allows for a lot of ambiguity on things like this that are kind of arbitrary. See http://www.iupac.org/reports/provisional/abstract04/RB-prs310804/Chap3-3.04.pdf where nothing is explicitly mentioned about it and inferences may be made in either direction. I see what you mean though about it being a bad thing to have a "Group (*nothing*)" in element articles. I think keeping this article with a change in title would be good. Maybe something like an article called Lanthanide/actinide group number Flying Jazz 05:19, 21 January 2006 (UTC)[reply]
In that case I suggest this article to be kept, retitled and changes nature from the definition and list of these groupless orphans to a history about this problem of orphanage. The original redirects (from articles like Uranium) are to be kept. Deryck C. 06:31, 21 January 2006 (UTC)[reply]
  • My idea of a new title: Group number of lanthanoids and actinoids, or even more "naughty", Groupless nature of lanthanoids and actinoids.
Oh dear lord! So it was you behind this all along, Deryck! That explains a lot! LOL --feline1 10:18, 21 January 2006 (UTC)[reply]
Does that? The major concern is, this article was started 1.5 years ago, when the "correct style of writing" on wikipedia wasn't well formulated yet. Deryck C. 10:42, 21 January 2006 (UTC)[reply]
Orpahans really do have biological parents, you know...except for a cloned orphan...who would have only one. I'm renaming this "Group number of lanthanides and actinides" and redirecting for now. All of Wikipedia should switch over to "-oid"...but I think that should take place all at once and can wait for another day. Maybe a year. The internet is too small. I keep seeing the same people over and over again. Flying Jazz 15:09, 21 January 2006 (UTC)[reply]

Plutonium[edit]

The graphic shows plutonium as a primordial element, but its longest lived isotope has a half-life of only 8×107 years. Its should really be in the same class as neptunium and americium. Physchim62 (talk) 16:31, 21 January 2006 (UTC)[reply]

See the discussion about this here: Talk:Periodic_table/archive_2#Naturally_occuring_elements. Of course, if that is true then Neptunium also would be naturally occuring, so I'm still confused about it, but changes should be made to the entire table template before the diagrams on these little side-aricles are altered.. Flying Jazz 17:07, 21 January 2006 (UTC)[reply]
I'll copy this thread to Talk:Periodic table and Wikipedia talk:WikiProject Elements to revive the discussion, which didn't seem to reach a conclusion. --Eddi (Talk) 19:39, 21 January 2006 (UTC)[reply]

Please coordinate with Group 3 article[edit]

Please coordinate future changes to this article with the group 3 elements article so we have a self-consistent pair of articles that don't contradict each other even though they might say similar things twice and repeat themselves. Flying Jazz 21:23, 21 January 2006 (UTC)[reply]

Uranium & Plutonium[edit]

From the legend, U and Pl are "primordial" instead of "naturally radioactive". I wonder why choose primordial? (both are okay in some sense, but why the former?) Deryck C. 08:03, 25 January 2006 (UTC)[reply]

Group Naming Suggestion[edit]

Maybe the American naming system should introduce Group C:

La: III C
Ce: IV C
Pr: V C
Nd: VI C
Pm: VII C
Sm-Er: VIII C
Tm: I C
Yb: II C
Lu: III B
—The preceding unsigned comment was added by Bernard222.152.24.178 (talk) 05:08, 22 December 2006 (UTC).[reply]

Merge into group 3 element[edit]

I decided to do this as this article duplicated exactly the same text and as such it should be uncontroversial. If anyone wishes to add material in the future about group 3, it would leave the two pages inconsistent as it is now. The way, the truth, and the light (talk) 07:37, 25 April 2008 (UTC)[reply]

Reverted. Here is the introduction to the group 3 article:
The Group 3 elements are chemical elements comprising the third vertical column of the periodic table.
IUPAC has not recommended a specific format for the periodic table, so different conventions are permitted and are often used for group 3. The following d-block transition metals are always considered members of group 3:
Here is introduction to the "Group number of lanthanides and actinides" article:
IUPAC has not recommended a specific format for the periodic table, so different conventions are permitted and are often used for the group number of lanthanides and actinides. There is no pre-existing physical entity for a "group" of elements. The notion is simply a convenient classification, since some elements have similar periodicities in their properties. This allows them to be arranged in columns that also happen to correspond with electron configurations.
This is not exactly the same text. It is very different text. Much of the remaining text is the same because the same four possibilities impact the issue of which elements are contained in which element category. For example, whether or not uranium is a group 3 element is a semantically debatable topic. Whether or not scandium is a group 3 element is not similarly debatable. Of course, in reality, scientists don't debate these issues because they're rather silly human classifications. However, as encyclopedia-makers, we need to concern ourselves with semantics and find an NPOV method of representing the group number for these elements. Please look at the template box for the Uranium article. Under "Group" you will find the text "n/a" that links, as it should, to the Group number of lanthanides and actinides article because Uranium is always characterized as an actinide. In contrast to this, the template box for the Scandium article correctly shows it as being definitively in group 3. Any editor who changes the group 3 article does not need to edit "Group number of lanthanides and actinides" if their changes only apply to Sc and Y. There would be no inconsistency in that situation. Before adding the redirect again, please ask for an expert opinion from one of the editors at Wikipedia:WikiProject Elements/Participants. Also, please review the discussion at Wikipedia_talk:WikiProject_Chemistry/archive03#Group_3. Flying Jazz (talk) 00:48, 26 April 2008 (UTC)[reply]
Those are not completely different, in that they both refer to the confusing situation surrounding group 3, and the rest of the article is indeed the same. I think that one issue should be addressed in one article, not two. True, they might diverge in the future, but is that a good thing? Someone reading only one of the articles (they don't even link to each other) would not get the whole picture.
I understand the element infoboxes, and given the situation, they're right. The way, the truth, and the light (talk) 01:47, 26 April 2008 (UTC)[reply]

The merge seems reasonable to me. --mav (talk) 13:28, 26 April 2008 (UTC)[reply]

I would agree with the merge as well. As for the "IUPAC Periodic Table of the Elements", see the second page of International Union of Pure and Applied Chemistry (2005). Nomenclature of Inorganic Chemistry (IUPAC Recommendations 2005). Cambridge (UK): RSCIUPAC. ISBN 0-85404-438-8. Electronic version., where the lanthanoids and actinoids are included in group 3. Physchim62 (talk) 15:40, 26 April 2008 (UTC) See also this IUPAC page Physchim62 (talk) 15:45, 26 April 2008 (UTC)[reply]
If IUPAC intended a consensus view of group 3, it would not have included in IR-3.5 on p 51 of International Union of Pure and Applied Chemistry (2005). Nomenclature of Inorganic Chemistry (IUPAC Recommendations 2005). Cambridge (UK): RSCIUPAC. ISBN 0-85404-438-8. Electronic version. "Optionally, the letters s, p, d and f may be used to distinguish different blocks of elements. For example, the elements of groups 3–12 are the d-block elements." This option would exclude f-block elements from group 3 and leave them "ungrouped." I think the reader is best served when they click an "n/a" in an elementbox if it does not direct them to the same article as clicking a "3" in an elementbox. One article is about a topic that may have some uncertainty about what is included within it, and the second article is about the nature of that uncertainty. In my mind, these are two very different, if related, issues. For example, see British Isles for the topic that may have uncertainty about what is included within it and British Isles naming dispute for the nature of that uncertainty. Even though I strongly believe I'm correct about what best serves the reader, if the consensus is that the reader is best served by a merge, then I don't care enough the issue (or anything else at Wikipedia for that matter) to continue an edit war with someone who is so adamantly opposed. Flying Jazz (talk) 22:41, 26 April 2008 (UTC)[reply]

I don't think we need an article about the "group number of lanthanides and actinides" because there are no references that deal with this topic explicitly (as far as I know). All I see so far is an analysis of the layout of various periodic tables. If the group number is not well-defined, let's leave it at that instead of writing about it at length. If the goal is to explain to the reader why the infobox has an "n/a", I suggest adding a short footnote explaining why. --Itub (talk) 07:43, 27 April 2008 (UTC)[reply]

"The Positions of Lanthanum (Actinium) and Lutetium (Lawrencium) in the Periodic Table", Journal of Chemical Education, 1982, 59, p. 634-636 deals with the topic explicitly but not completely. It compares La and Ac in group 3 vs Lu and Lr based on the chemical similarity of these elements to Sc and Y. It concludes by stating that Lu and Lr are more "group-3-like" than La and Ac and the article strongly recommends that a periodic table like [1] should be preferred over one like [2]. This article continues to be cited to criticize tables that place La and Ac in group 3. Journal of Chemical Education, 2002, 79, p. 60 states "Whether one or the other end of both 15-element sequences should be really included remains controversial," and see, for example, [3]. However, the 1982 JCE article is an incomplete analysis because it does not consider the placement of a marker for all lanthanides and actinides (like the current Wikipedia and IUPAC tables) or the pros and cons of such a marker. For example, it might give the impression that the f-block is 15 elements long instead of 14. The complete issue was addressed very briefly at [4]. It was also addressed at length by me and others off Wikipedia at [5]. On Wikipedia, it has been discussed about a half-dozen times or so, like any topic would be where multiple opinions and versions of something exist in the literature. Students and educators really are interested in why these different layouts exist, and I thought that a goal of Wikipedia was to serve them. Of course, you are right that we don't *need* an article about the topic, but if articles were only written based on need then none would exist because we don't need Wikipedia at all. Or perhaps one would exist. All the articles at Wikipedia could be merged into one big article called "stuff," and the esoteric details about less important stuff could all be included in footnotes. Flying Jazz (talk) 14:18, 27 April 2008 (UTC)[reply]
I don't mean we don't need it in the trivial sense you mock. What I mean that I don't think this is a topic that one can write an encyclopedia article about, at least according to Wikipedia's policies. The paper you refer to is about the more common issue of the placement of La/Lu, but it hardly has anything to do with the group number of the lanthanides. The other websites and forums you refer to are not reliable sources for ascertaining the notability of a topic. --Itub (talk) 21:34, 27 April 2008 (UTC)[reply]
A group is a vertical column of the periodic table. The elements in question (La/Lu and Ac/Lr) are lanthanides and actinides. So the issue about the placement of La/Lu and Ac/Lr is precisely the issue of the group number of lanthanides and actinides. Anyway, that is how the issue is discussed in JCE 1982, 59, p. 634-636. The things you wrote have hardly anything to do with each other are actually identical to each other. Different periodic tables have different group numbers for certain lanthanides and actinides, and there is published literature in peer-reviewed educational journals about the differences. I certainly agree that the forums at apsidium.com and webelements.com are not reliable sources. I included them in the talk page to show how they cite the academic literature on the subject and to demonstrate that there is sufficient interest in this topic so that (in my view) Wikipedia would provide a valuable service by having an encyclopedia article on it. I also certainly didn't mean to mock you or your ideas. However, I did mean to mock a recent trend I've noticed both here and elsewhere to merge and redirect certain Wikipedia chemistry articles. Whether or not a topic is sufficiently notable for inclusion in the encyclopedia is up to our interpretation of policy in each specific case. Rather than stating "according to Wikiepdia's policies," could you state which policy you are referring to and how you are interpreting it here? My view is that if Wikipedia has a separate article for every group of the periodic table, then the unique status of the lanthanides and actinides with or without La/Lu or Ac/Lr must also be addressed. The periodic table itself is sufficiently notable, I think, to warrant an article explaining this exact issue. Flying Jazz (talk) 03:50, 30 April 2008 (UTC)[reply]
La and Lu are not identical to the lanthanides, are just a small subset of them. Those are the only lanthanides that often can be said to have a group number (whether the tables that put a little star under Y and then the 15 lanthanides as a footnote really mean that all 15 lanthanides are in group 3 is arguable). There is also some debate about the group placement of He, but that doesn't make it a debate about "the noble gases". Then, a more accurate title for this article would be "Group number of lanthanum, lutetium, actinium, and lawrencium". Sounds too verbose? Then I suggest reducing it to "Group 3 elements", as that's the only group to which all the elements in question sometimes belong. Oh, wait! That's where it was merged already! The status of the lanthanides in general can also be mentioned in the article about lanthanides, etc. Regarding Wikipedia policies, first I meant the requirement for multiple independent references explicitly addressing the topic (WP:N), as so far I've only seen one (the J. Chem. Ed. article). Second, that this seems to be blowing up a minor "debate" out of proportion by giving it its own article rather than incorporating it where it belongs. As such, I consider it a type of content fork. Third, that the way the article was written ("some tables this, some tables that") is too close to collecting evidence and writing your own synthesis, which goes against WP:SYN. --Itub (talk) 05:20, 30 April 2008 (UTC)[reply]
On April 26, Physchim62 wrote: "the lanthanoids and actinoids are included in group 3" and cited an IUPAC reference to advance that view, so obviously La and Lu are not "the only lanthanides that often can be said to have a group number." There are multiple options that may be supported by IUPAC nomenclature statements. I agree with you that the meaning of footnote indicators in a table is arguable. In my opinion, arguable information is interesting information, and presenting arguable content in an NPOV fashion is a good thing. I also agree with you that some tables place He in group 2. The reason why that does not warrant its own Wikipedia article, in my opinion, is because the decision about where to place He is not based on chemical considerations, but on the goals and preferences of the table publisher. A table that emphasizes electronic configuration over chemical similarity will place He in group 2, so having an article about that would be similar to an article about whether one publisher prefers one color for their cover over another. However, unlike the case with helium, the decision about the group number of lanthanides and actinides is based on the real world data of chemical similarity comparisons to Sc and Y. As I discussed above, the subject is addressed three times at Journal of Chemical Education, 1982, 59, p. 634-636, Journal of Chemical Education, 2002, 79, p. 60, and Journal of Chemical Education, 2002, 79, p. 944. What constitutes "explicitly" addressing a topic is debatable. This isn't an area of continuing research, so the first JCE article is the only one (to the best of my knowledge) that uses chemical data to address the issue. I disagree with you about WP:N but I understand your position. Whether three meets the requirement for "multiple" is debatable, particularly when only one of the three use data. The other two policies you cited seem to work in my favor. WP:SYN requires that the sources be put together to advance a position. The article did no such thing. WP:SYN states "Summarizing source material without changing its meaning is not synthesis; it is good editing." WP:CFORK states "Different articles can be legitimately created on subjects which themselves represent points of view" Many chemists forget what it can be like for educators when they first teach basic things to students. I imagine a high school chemistry student asking their teacher, "Why does this table put some lanthanides and actinides in a different group than that table?" The acknowledgment that "some tables do this and some tables do that" together with chemistry-based explanations for the different group numbers assigned by different tables serves a valuable purpose. Wikipedia should help. Flying Jazz (talk) 12:27, 30 April 2008 (UTC)[reply]
This is more WP:UNDUE; this might have been discussed in J. Chem. Educ., but so have many things. Why should it be discussed on Wikipedia? Are chemists really confused by the current situation? Do they feel unsure as to whether dysprosium is more like yttrium than like bromine? Do they wonder whether the phrase "groups 1–12" includes the lanthanoids and the actinoids (or however you wish to call them)? IMHO, learning chemistry involves learning the exceptions as much as learning the rules, but this "article" doesn't do anything in that direction. The very first sentence in the version promoted by Flying Jazz is demonstrably false: indeed, the references given in that version and on this talk page show it to be so. The merge should stay, and this page should be salted. Physchim62 (talk) 16:17, 1 May 2008 (UTC)[reply]
Physchim wrote: "the lanthanoids and actinoids are included in group 3." Itub wrote that La and Lu "are the only lanthanides that often can be said to have a group number." Then Physchim wrote "Are chemists really confused by the current situation?" The answer to that question, when it comes to the physical reality of elements, is no. They are most likely not confused. The answer to that question, when it comes to the group numbers that IUPAC has or has not assigned to lanthanoids and actinoids, seems to be yes based on yourself as an excellent example of a confused person (assuming you are a chemist). The statement "IUPAC has not recommended a specific format for the periodic table" is demonstrably correct. IUPAC uses a certain periodic table, but usage is far different from recommendation. We know this must be correct because the Redbook states: "Optionally, the letters s, p, d and f may be used to distinguish different blocks of elements. For example, the elements of groups 3–12 are the d-block elements." This option would result in a different periodic table than the one IUPAC uses. However, this option still would result in an IUPAC-recommended table. I am unfamiliar with the phrase "this page should be salted," but I understand it can be frustrating to have your confusion pointed out to you. If you are confused then how many less knowledgeable people are also? Wikipedia exists to help them learn about the situation and to try to explain that different options in something as fundamental as the periodic table may exist. Flying Jazz (talk) 14:48, 3 May 2008 (UTC)[reply]

My gut feeling is that we should stick with IUPAC here. I hate to be a pest, but can someone provide me with a ref stating where IUPAC stands on this issue? Thanks, Antelantalk 15:47, 3 May 2008 (UTC)[reply]

Exactly. The only relevant IUPAC reference is discussed above. International Union of Pure and Applied Chemistry (2005). Nomenclature of Inorganic Chemistry (IUPAC Recommendations 2005). Cambridge (UK): RSCIUPAC. ISBN 0-85404-438-8. Electronic version.. See the unnumbered second page where the IUPAC table is given and see IR-3.5 page 51, first paragraph where the issue of groups is addressed. That reference will show you the issue we are discussing, but it will not decide for us whether the issue merits treatment in its own article. That is the arguable point for editors here to decide. Flying Jazz (talk) 16:28, 3 May 2008 (UTC)[reply]
Thanks for the reply and the document. From reading, it seems that there are only 2 species that are always Group 3, while the rest of the lanthanides and actinides are debated. Is this correct? (And from the document I realize now that I should be saying "lanthanoids and actinoids".) Antelantalk 16:33, 3 May 2008 (UTC)[reply]
Mostly correct. Only Sc and Y are always in group 3. They are not lanthanoids nor actinoids. Also...chemists usually have better things to debate. The issue that has been debated in the chemical education literature is a subset of the entire issue: whether Lu and Lr are better to locate in group three than La and Ac. Flying Jazz (talk) 16:59, 3 May 2008 (UTC)[reply]

Okay... - I wish to add a few comments as the original creator of the Ungrouped Elements article. First of all, IUPAC is not God. The whole point of the existence of the article is that many people consider the f-blocks as group-numberless whereas others consider them as group 3 (or something else). The current state, with the whole lanthanide thing merged into the group 3 article, suggests a presumptive non-NPOV: Wikipedia endorses the notion that lanthanides and actinides belong to group 3, which is something we should deliberately avoid.

As for the lengthy litigation above, I wish to excuse myself from the main discussion. I'm too fed up with the way people dispute over things on Wikipedia. However, I'd suggest that we rewrite the separate article with new sourcing to support both views and put the article back in place. The lack of sourcing in the lanthanide and actinide article arose because the article was written very early on in Wikipedia's history, when rigorous sourcing policies have not yet been implemented. --Deryck C. 10:16, 4 May 2008 (UTC)[reply]

Argh, not this old chestnut again! :) I find myself in almost 100% agreement with Flying Jazz, who has provided a splendid set of references to the original literature, and examined the issues at some length. Further points that I would add:
  • the view has been expressed above as to what "chemists" think. This is all very well, but we should not forget that wikipedia is a *popular* and *tertiary* source with a *pedagogic function*, useful for *students* and *the general public*. I certainly feel the Group number of lanthanides and actinides article served a useful purpose in clarifying things for the non-specialist reader - and indeed, its very existence came about because of confusion on the part of the students who were writing wikipedia articles in about 2003 :) To put it another way: I seem to be getting a whiff of the notion that "if people understood chemistry properly, they'd see this article was a bit pointless" - that is tautological and silly, if you think about it: people who need to look things up in encyclopaedias, by definition, do not understand things properly and require clarification.
  • The Group number of lanthanides and actinides article had been stable for a good couple of years and was arrived at through care consideration and WP:CONSENSUS between editors. It should not be done away with because some new broom blundered in and thought everything should be done differently.
So, I vote strongly in favour of retaining Group number of lanthanides and actinides as a separate article. A discussion of the group number of the actinides for example, does not belong in an article entitled Group 3 elements any more than it belongs in Group 6 elements--feline1 (talk) 22:39, 5 May 2008 (UTC)[reply]
The lanthanides and actinides, if you don't consider them in Group 3, are at least related. The information, by the way, was already all in the group 3 element article. There doesn't seem to be any good way to separate the article - we can't talk about where the lanthanides belong without talking about what Group 3 is, and we can't discuss Group 3 completely without mentioning the lanthanides and actinides. All the sources that have been cited really don't change this. The way, the truth, and the light (talk) 23:21, 5 May 2008 (UTC)[reply]
There doesn't seem to be any good way to separate the article *to you* - the prior editorial consensus, which you have ignored, was that the article split was good.--feline1 (talk) 09:37, 6 May 2008 (UTC)[reply]
I'm not going to repeat my arguments, but just summarize a conclusion that I didn't write explicitly before. I think this is a great topic--for an essay or a J. Chem. Ed. article. But not for an encyclopedia article. It is just too narrow and not established enough. I have nothing else to add except that consensus can change, and that many early "consensuses" were crap, dating from the time where Wikipedia was even more chaotic than it is now! --Itub (talk) 10:26, 6 May 2008 (UTC)[reply]
Or "consensus" may change because someone makes a decision when unaware of previous consensus, and then, humans being what they are, is stubborn and doesn't want to have their mind changed ;)--feline1 (talk) 14:15, 6 May 2008 (UTC)[reply]
Of course consensuses change over time, but not when more than half of the commenting editors argue against changing it. --Deryck C. 10:23, 7 May 2008 (UTC)[reply]
More than half? I may be missing someone, but so far I see 4 in favor of merging and 3 against. --Itub (talk) 10:53, 7 May 2008 (UTC)[reply]
Yes but as you're doubtless aware, consensus on wikipedia is not measured by voting, as some people's opinions carry more weight than others (not least because they are right) :) --feline1 (talk) 11:20, 7 May 2008 (UTC)[reply]


It might help if we get some history here.

  • John Newlands's periodic table (1864) was the first widely publicized table that had many elements in today's lanthanides and actinides. In his table, La, Ce and U aligned with Boron; Di (Pr and Nd were thought to be one element) aligned with Nitrogen; Ru aligned with Oxygen. The lanthanides and actinides found at the time were therefore scattered across groups 3, 5 and 6.
  • Mendeleev's original periodic table (1869) put Di (Pr and Nd, see above) in III, Ce and La in IV and U and VI. Again, they're scattered.
  • Most modern periodic tables put Sc, Y, La and Ac in the same column for group 3; Ce to Lu, and Th to Lr do not have group numbers. This version is adopted by most countries' university entrance examinations. (eg. SAT, GCE) On the other hand, Webelements put Lu and Lr onto the column with Sc and Y, instead of La and Ac. It would be tempting to conclude that since La, Lu, Ac and Lr all somehow appeared in group 3, we should put the entire lanthanide and actinide series into group 3. However, no one has actually put any of the elements Ce to Yb and Th to No into any numbered group explicitly. It's therefore a heavy disruption of NPOV if we simply presume they belong to group 3 and merge the two articles together. --Deryck C. 14:41, 7 May 2008 (UTC)[reply]
What would people think of a !vote? Antelantalk 06:05, 8 May 2008 (UTC)[reply]
I don't think a vote will help, since the people who have commented are so evenly split. In reply to Deryck Chan's statement that "a heavy disruption of NPOV if we simply presume they belong to group 3 and merge the two articles together", I think there's a misunderstanding. What I'm saying is that they don't consistently belong to any group, but we don't need an article specifically to say that. We don't need an article to say that the lanthanides don't belong to any political party either. ;-) --Itub (talk) 09:13, 8 May 2008 (UTC)[reply]
Have you ever encountered a chemistry student who wondered which group the Lanthanides were in and wanted to look it up in an encyclopedia? Yes. Have you ever encountered a chemistry student who wondered what political party the Lanthanides were in and wanted to look it up in an encylopedia? No. QED, an article on it would be useful. If anything, I would propose merging the article into being a section of Group (periodic table). How about that as a compromise? I think the discussion would be more useful and readily found there than putting it in Group 3 element (although the latter article should have a link to it).--feline1 (talk) 09:41, 8 May 2008 (UTC)[reply]
Sure, that could work. Have a section on Group (periodic table) about the lanthanides and actinides, describing their unclear situation, and also have a section on Group 3 element mentioning that tables often have La and Ac in that column, sometimes Lu and Lr, and sometimes none of the above. --Itub (talk) 09:47, 8 May 2008 (UTC)[reply]
Cool. I had a look at Group (periodic table) and didn't like it - what's with all the "titanium family", "manganese family" stuff?! (there are a few IUPAC approved trivial names, but all this family business is daft) - could do with some tidying up! So, I say, let's do that, and put the lanthanide/actinide blurb in there too.--feline1 (talk) 09:53, 8 May 2008 (UTC)[reply]

(unindent)"Titanium family" has been used in some books (see [6], although there are some false positives) so at least it's not made up. That said, I wouldn't cry if we deleted those families from the list. At least the links should be removed because they are confusing--for example, titanium family link just redirects to Group 4 element, and having it linked on the same line as the link that says "Group 4" could suggest that the two links go to different places. --Itub (talk) 11:05, 8 May 2008 (UTC)[reply]

I agree about putting the information in Group (periodic table). Good idea, feline. As for the other business, IUPAC sayeth, "If appropriate for a particular purpose, the various groups may be named from the first element in each, for example elements of the boron group (B, Al, Ga, In, Tl), elements of the titanium group (Ti, Zr, Hf, Rf), etc." Calling them a family instead of a group is fairly common, I think, although I don't like it. Flying Jazz (talk) 12:09, 8 May 2008 (UTC)[reply]
Sounds like a good idea to make it a subsection of Group (periodic table). (a bit offtopic) reply to Itub: it *is* a disruption of NPOV because the name of the article says "Group 3". No political party is mentioned in the article name or content, so there's no political party NPOV problem. --Deryck C. 18:46, 8 May 2008 (UTC)[reply]