Wikipedia talk:WikiProject Elements

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WikiProject Elements (Rated Project-class)
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Archive and redirect Wikipedia talk:WikiProject Elements/Isotopes to here?[edit]

The brunt of the isotope work has been done a few years ago. How would you all feel about "closing" Wikipedia talk:WikiProject Elements/Isotopes and redirect (soft or hard) the discussions of isotopes to the main element page? Headbomb {talk / contribs / physics / books} 18:16, 1 July 2015 (UTC)

OK with me. Is stable long time indeed. Does this require any other action (like formal closing of a WP:task?). I mean, lets do it right in one time. -DePiep (talk) 19:36, 1 July 2015 (UTC)
I don't think this requires any 'formal' action. I don't want to close the taskforce itself, just centralize discussions related to isotopes on this page rather than on the isotope taskforce page, given its low activity and the majority of the issues dealing with our approach to isotopes resolved. I just want to gauge the mood before doing anything (e.g. prefer the isotopes discussions to remain on the isotopes subpage). Headbomb {talk / contribs / physics / books} 19:53, 1 July 2015 (UTC)
With this, I'm less supportive (but do go ahead). My headache is that WikiProjects and subs are getting mixed up. Even now I still get confused (into improductively) mixing up WP:CHEMISTRY and WP:CHEMICALS. Can you see the problem? Overlapping WikiProject issues appear on different WP pages. This is why I request: then merge all of it. -DePiep (talk) 20:06, 1 July 2015 (UTC)
The issue with WP:CHEMISTRY and WP:CHEMICALS is most likely that WP:CHEM is ambiguous (as an abbreviation), and that people might not know that WP:CHEMICALS even exists. That, and for most chemicals, they should just be tagged by {{WP Chemicals}} and not both {{WP Chemistry}} and {{WP Chemicals}}. Whereas WP:ISOTOPES clearly is a taskforce of WP:ELEMENTS (used to be its own WikiProject in the past however, but it has been merged with it eons ago), and you tag it with {{WP Elements|isotope=yes}}. This is really about closing down a discussion page and redirecting the traffic to this one.
I'll wait for others to comment on this before proceeding. Headbomb {talk / contribs / physics / books} 18:17, 6 July 2015 (UTC)
I get it that WP:isotopes is not that confusing. Go ahead as you think best. -DePiep (talk) 19:23, 6 July 2015 (UTC)
Yes, I understand your point, and I agree as well.--R8R (talk) 01:07, 7 July 2015 (UTC)
I agree, go ahead. But what to do with the existing discussions on the page? I suggest that it be moved lock, stock, and barrel to an archive of this page, and then a redirect created to this page. That way, there would only be one set of archives to examine. YBG (talk) 02:32, 7 July 2015 (UTC)
Sounds good. Double sharp (talk) 20:12, 25 July 2015 (UTC)

Hmm, I moved it to Wikipedia talk:WikiProject Elements/Archive Isotopes, but then it doesn't show up on the main header. But then it doesn't show up. Do I need to give it a number? If so, I'll reserve 21 for it and then skip over from 20 to 22 for the main archives. (As it stands, 15 already cuts through the story.) Double sharp (talk) 07:45, 22 September 2015 (UTC)

OK, I gave it the number 21. Then we'll just have to note that there are two special archives: 15 (ginormous metalloids discussion) and 21 (all the old isotope material). Double sharp (talk) 07:45, 22 September 2015 (UTC)
Thanks for doing it. It sort of fell off my radar with the start of the semester and all. Headbomb {talk / contribs / physics / books} 17:14, 22 September 2015 (UTC)

Question regarding the Periodic Table[edit]

A video was released earlier today on a YouTube channel I watch named Periodic Videos. The video was titled, "Your periodic table is probably WRONG" and it is linked here:

It was discussing a paper released in Nature back in April that was bringing into question the commonly structured setup of the lanthanides and actinides on the table. The paper is linked here:

My question is, was anything changed in our articles here in regards to this, such as how we portray the periodic table and, if not, what information and testing from scientists in the field would be necessary for us to then change it? Or is there an organization or society that would have to put out an official dictum before we make any changes? SilverserenC 21:43, 12 August 2015 (UTC)

  • First of all, see what trouble The Prof has explaining the issues because he keeps using an 18-column PT. Half of the time is eaten by the "move that bottom block back into the PT" wrestling. (IKEA comes to mind - including the leftover parts). Why don't they have a 32-column PT in Nottingham to start with? There is no reason to complain, at the end of the video, that PT's are drawn such a way because of drawing ease (and then use a PT too easily drawn yourself). By all means, how is a classroom wall not an ideal size for the 32-column PT? On top of this, the 18-column cardboard PT used in the video is ambiguous about how to squeeze in the bottom block. Ouch. Talking about drawn by ease. No wonder The Proff never noticed.
Next. The opening notion of the video (Group 3 should be/could be to the right of the Ln/An block, creating a group 3 having Sc/Y/Lu/Lr) is how we show it already a long time here. See for example Scandium (the micro PT in the infobox), Periodic_table#Overview (note the asterisk locations), and here (twice). Not correct to say that the bad form is used "everywhere"!
And no, we did not draw it this way 'because it is easy to draw'. We discussed this here, (especially [here]; Sandbh is the editor to follow) over a year ago. To PT theoriser Eric Scerri it is not new either. The news is that this is news to The Proff. In the Video The Prof even shows that (our) wikipedia overview (at 6:18).
In the end of the video, the speculation takes over. Already the video title says probably WRONG, later the words 'perhaps' and 'could be' are added (from 5:45). Quite a bluff to claim that PT's are drawn by what is easy, while only having speculation to inject. It could be that the Proff now had a bad day because all the videos that show his PT's "everywhere" (his tie for sure, his boxer short maybe) need a reshoot.
And no, there is no vetting institute for changes to "the" PT. It is based on reasoning. Eric Scerri noted that there are some 700 variants dawn of the periodic system, most sound but by a different principle. So the Proff saying it is WRONG may be itself the wrong part in the story.
Recap: 1. throw out all your 18-column PTs, use the 32-column form. If 18 is necessary, don't be ambiguous with the asterisks. 2. Always check Wikipedia. 3. Don't claim "wrongs" together with "possibly, probaly, could be". 4. This also applies to ties and boxer shorts. -DePiep (talk) 00:49, 13 August 2015 (UTC)
Added talkpage archive link where it becomes useful [[1]], by User:Sandbh (after rereading Lavell, Scerri and Jensen). Also DoubleSharp is to follow, he's into Cotton at the moment for this :-). -DePiep (talk) 07:53, 13 August 2015 (UTC)

Since I am named above I take the liberty of adding a few comments relating to the Poliakoff video and the question of group 3. Interesting video. However the authors of the article in Nature magazine, who measured the first ionization of Lr, did not make an argument that it should be placed in group 3 as Poliakoff claims. It was rather the science news articles published in places like Scientific American. If one looks closely at this observation one finds that it still does not settle the issue conclusively. In my own book, "A Very Short Introduction to the Periodic Table", OUP, 2011, I give what I believe to be a categorical argument in favor of group 3 as Sc, Y, Lu, Lr. It is that the periodic table should be presented in its long or 32-column and that all elements should be shown in order of increasing atomic number. This settles it conclusively apart from the remote possibility, which coincidentally was shown of the video, of a table that breaks up the d-block into two highly irregular portions consisting of one and nine groups, separated by the d-block. I cannot believe that nature is so perverse as this. The 32-column table shown in the video is fundamentally incorrect. Just look at the triads. For all other transition metal groups the atomic number triads consist of the second , third and fourth elements in the group. In the case of group 3 as shown in that table it is the first, second and third elements that form a triad. This is highly inconsistent. Why should the d-block be the only group that is split up in this anomalous fashion? It makes no sense. please see — Preceding unsigned comment added by (talk) 00:06, 17 August 2015 (UTC)

Understood this reply is by Eric Scerri. Thanks for this eloquent contribution. -DePiep (talk) 09:18, 18 August 2015 (UTC)
@Prof. Scerri: OTOH: the s-block splits up in a similar way too, where 2/10/18 forms a triad but not 1/3/11. But one thing I'd like clarification for: what do these atomic number triads mean anyway? What is so important about them, that you mention them as a strong argument? I'm genuinely curious. (?_?) Double sharp (talk) 12:54, 11 September 2015 (UTC)
See: Eric's paper 'Explaining the periodic table, and the role of chemical triads', here. Cancel the join up prompt and read on screen. Sandbh (talk) 01:25, 18 September 2015 (UTC)

An 18-column PT is history. It's 32-column now[edit]

Each person born in this century should learn the Periodic Table in 32-column form. -DePiep (talk) 20:45, 18 August 2015 (UTC)

Now, if only there was an effective way to enforce that. Getting the IUPAC approval (possibly also ACS for the U.S., which does have a tradition to stand out when it comes to world standards) could do the job... Except it wouldn't be enough anyway. Like in Russia, they still commonly teach the hardcore old school Mendeleev's 8-group version (even though the 18-column form is slowly gaining usage, it is happening veeeeery slowly). And then practically, of what use would be for the non-scientists? The table grows super wide to include the elements comparably few people even work with? The f block is not discussed in schools, and for almost anyone else, the f block isn't a problem either. In fact, this whole group 3 question is extremely minor for any practical purposes. Mostly because few people work with or even just actually learn the lanthanides. So we would get one theoretical question solved at the expense of making the table almost twice as large as it is now, making much more empty space (compare visually the empty space in a 18-group table and a 32-group table... In fact, in the latter, there is more empty space than space filled with any useful information!)
All that said, yes, it would be great if we could get over the human conservatism and accept the group 3 is -Lu-Lr, rather than -La-Ac. Yet reflecting that by making the 32-col table the standard is just too much for any practical purposes. It would unnecessarily complicate the table to solve a problem with the elements few people even actually learn, not to say work with.--R8R (talk) 22:48, 18 August 2015 (UTC)
You lost me when you wrote "... IUPAC approval" (in your 2nd sentence). -DePiep (talk) 23:07, 18 August 2015 (UTC)
Aha. Great to say, "I don't like it, won't listen." Yet this is the reality. People often listen to those who they seem as the standard makers. IUPAC is not omnipotent -- but it does influence things. Like it brought us those meh unun- names for the superheavies. Or the whole standard for the chemical nomenclature. It is not wise to ignore this just because you don't happen to like this. (Most of my re isn't about IUPAC anyway -- and I'd love you to discuss it.)--R8R (talk) 21:08, 19 August 2015 (UTC)
I can agree. IUPAC can influence things, but you actually wrote "inforce [enforce]". Well, that is not possible. We are here to improve the PT by arguments, not by force. So I'm happy to read the eloquent contribution by Eric Scerri. (And really, really, never ever write "32-group table" again. It's 32-column. That's part of the point). -DePiep (talk) 22:24, 19 August 2015 (UTC)
By "enforce" ("inforce" was a typo) I mean "make this the standard." Making a better table is great, and there is some actual reasoning beyond the structure of the new table, but there must be some goal beyond just knowing you've made a better table, like sharing the knowledge, and you specifically say, "Each person born in this century should learn the Periodic Table in 32-column form." And to make it the standard of learning for the new humans... well, I don't see how that verb "enforce" contradicts your original idea.
Also, I argue the 32-col (yeah, point taken) table would be impractical in real life, for the reasons I've listed above. To educate the new humans, I would use the regular 18-col table with group 3 being Sc-Y-*Lu-**Lr instead of the Sc-Y-La*-Ac** or Sc-Y-*-** many people use today.--R8R (talk) 22:51, 19 August 2015 (UTC)
Or possibly go Ba-*-Lu and Ra-**-Lr, this would work, too--R8R (talk) 23:03, 19 August 2015 (UTC)
Again: don't mix up PT structure with PT presentation. Whatever group 3 is: show it in 32-col form. -DePiep (talk) 23:21, 19 August 2015 (UTC)
I like how you say, "32 columns, and that's it," yet specifically ignore my concerns on its actual usage.--R8R (talk) 08:15, 20 August 2015 (UTC) not what I said. I say: Whatever you want to show, show it in 32-col form. The asterisk-to-cellar graphic construction does not clarify anything. Especially the group 3 issue. -DePiep (talk) 20:31, 20 August 2015 (UTC)
  • Mendeleev originally drew a 10-column PT (with groups I–VIII; group VIII has 3 columns - even today). Later on ca. 1900, the noble elements were added (11-column PT). -DePiep (talk) 23:29, 19 August 2015 (UTC)
    • It was an sort-of-11-column PT at first, with group VIII having 4 columns (Fe/Co/Ni/Cu; Ru/Rh/Pd/Ag; Os/Ir/Pt/Au). Cu, Ag, and Au appeared twice; once in group VIII and another time (bracketed) in group I. (If he didn't do this, only group I would not bifurcate; but the problem is that Cu, Ag, and Au show oxidation states higher than +1). However, preferring Platonic symmetry to inconvenient facts of chemistry, Cu, Ag, and Au were soon ripped out of group VIII. Double sharp (talk) 08:19, 20 August 2015 (UTC)
    See the actual 1871 table, it has only 8 columns. The current version has (kinda) 10 columns, but I specifically said, "8-group."--R8R (talk) 08:15, 20 August 2015 (UTC)
The rightmost column is a bit confusing in this. For starters, I'd never allow multiple elements in one cell/column - that's why they are (different) elements. -DePiep (talk) 20:40, 20 August 2015 (UTC)
  • By now, my favorite PT form is the 32-column PT on a cylinder, with a screw. The screw is 1/period: 10Ne meets 11Na. -DePiep (talk) 00:00, 20 August 2015 (UTC)

By decree of IUPAC, all chemistry classrooms must have walls long enough for a 32-column periodic table. NO EXCEPTIONS. shoy (reactions) 13:11, 20 August 2015 (UTC)

And paper aspect ratios? (^_-)-☆ That is honestly the main reason why 18-column will still go strong for a while longer even if 32-column is superior, if you ask me: 18-column fits paper aspect ratios better (and it lets people equivocate about the composition of group 3, but that's not something we should be encouraging). Double sharp (talk) 13:21, 20 August 2015 (UTC)
Also, I would need a way longer shower for my periodic table shower curtain. shoy (reactions) 15:12, 20 August 2015 (UTC)
I don't have the impression that IUPAC enforces (but please do illustrate). The Prof in Nottingham, Eric Scerri, and we at WP:ELEM all have been free to think & build our own PT presentation. -DePiep (talk) 22:38, 20 August 2015 (UTC)
It doesn't: it can only recommend. Double sharp (talk) 05:52, 21 August 2015 (UTC)

Not that everyone follows everything given in the IUPAC PT as well (aside from the equivocation on group 3, which we should really get rid of). I bet everyone's seen at some point a periodic table with H floating around somewhere in the middle instead of being over group 1. (And the periodic table diagrams in Greenwood & Earnshaw's 2nd edition float both H and He this way!) And I bet most PT manufacturers include the unconfirmed elements near the end (113, 115, 117, and 118), even though the IUPAC PT doesn't yet. Double sharp (talk) 13:24, 20 August 2015 (UTC)

thread split[edit]

Flying Jazz appears to have split the thread at User talk:Silver seren#Question about periodic table layout, with some stuff about IUPAC at Talk:Group 3 element#IUPAC committee decides that the organization of the periodic table isn't their business. Double sharp (talk) 11:09, 24 August 2015 (UTC)

Must be intended to "simplify" matters. As is the introduction of transition metals in the discussion. btw, what is "the organisation of the PT"? -DePiep (talk) 15:10, 24 August 2015 (UTC)
I imagine from the contents of their post that it's the placements of controversial elements, which is in practice the composition of group 3. Double sharp (talk) 15:54, 24 August 2015 (UTC)


FYI: Wikipedia:Featured picture candidates/Periodic Table of the Elements Nergaal (talk) 15:12, 31 August 2015 (UTC)

Could somebody please start from this svg and update it with the current color scheme and IMO remove the ionization energies and see if the result is FP-worthy? Nergaal (talk) 15:49, 21 September 2015 (UTC)
Since you ask: not me. I remember the name Nergaal and it does not sound inviting. But hey, maybe you have friends left, elsewhere. -DePiep (talk) 21:27, 21 September 2015 (UTC)
You seem to have a problem understanding what I said. I didn't say "hey buddy do me a favor". You in particular made sure to make me stop caring about this project, but there might be other people here that care to improve the project without creating unnecessary drama. Nergaal (talk) 17:55, 24 September 2015 (UTC)
You asked for cooperation. I answered. But don't worry, I'm leaving WP for exactly the same reason. -DePiep (talk) 22:38, 24 September 2015 (UTC)
Oh and just to be clear: I remember your name, without research, just because you made a fool out of good ELEM editor Sandbh and then got away with a reduced block because of your admin friend drmeis. This is your behaviour vs Sandbh's, so you are left to explain why I would be the cause for you leaving the project (unless you don't like someone pointing things out - then shoot the messanger). -DePiep (talk) 22:52, 24 September 2015 (UTC)
I think you got things wrong. I have no idea who that admin is, but if it was you who got me blocked over the war at other metal which was later agreed widely to my initial move, then I congratulate you for doing great work. Nergaal (talk) 19:40, 25 September 2015 (UTC)
I said: you fucked Sandbh. -DePiep (talk) 00:20, 26 September 2015 (UTC)
"I have no idea who that admin is" you say. Well, it is the admin who unblocked you prematurely (immaturely) in your 'other metal' disruptions. See the Nergaal block log. Of course you don't know. -DePiep (talk) 00:48, 26 September 2015 (UTC)


After looking at WP:ELEM/PP: I dunno why indium is so popular now, but maybe we ought to get it to GA due to all this attention (it's not that far off, I think.) Double sharp (talk) 12:20, 11 September 2015 (UTC)

Could be a big site linking to it, or other random events. I checked the history of PP and the last half year its typical 10-15,000 hits per month. Gold and Al (both C class) has been in top 5 the last half year with 100,000 hits per month. Just FYI :-) Christian75 (talk) 07:50, 13 September 2015 (UTC)
It happend only at one day, so this looks like a link from a high ranking internet site. --Stone (talk) 17:47, 13 September 2015 (UTC)
What day? Is there any correlation between that and some recent news? YBG (talk) 22:17, 13 September 2015 (UTC)
@YBG: 2015-08-13[2] Christian75 (talk) 15:57, 14 September 2015 (UTC)
Could this be related? YBG (talk) 16:29, 14 September 2015 (UTC)

See Talk:Indium#Indium article views on August 13, 2015. Double sharp (talk) 12:29, 18 September 2015 (UTC)

CIAAW Standard Atomic Weights updated: 2013 into 2015[edit]

CIAAW has updated, by announced biannual pattern, their "Standard Atomic Weights" from 2013 into 2015 [3]. -DePiep (talk) 19:27, 17 September 2015 (UTC)

Yes, I updated List of elements with this information on 31 August. I checked the infoboxes, but only one (Yb) hadn't been updated (which I proceeded to do). Double sharp (talk) 12:29, 18 September 2015 (UTC)
Yes, only Yb has changed at CIAAW between 2013–2015. The other edits in that List must have been correctionss (were wrong in 2013 already). The spreadsheet is not updated yet. By the way, the change for Yb is quite big: 2013: 173.054; 2015: 173.045. Could it be that they have corrected a typo? ;-) -DePiep (talk) 22:05, 20 September 2015 (UTC)
While that would be hilarious, I think the fact that the uncertainty changed as well (Yb 2013: 173.054(5); Yb 2015: 173.045(10)) makes me think it's just a coincidence. Double sharp (talk) 07:35, 22 September 2015 (UTC)
An interesting idea would be to have an in-project page showing how these atomic weights have been changing. We could then search the old values and update them on sight. Double sharp (talk) 07:36, 22 September 2015 (UTC)

H and He: because that was the only issue that never spiralled off into a megadiscussion[edit]

Talk:Periodic table#Placement of hydrogen and helium. (Will update link when it gets archived.) Double sharp (talk) 07:25, 21 September 2015 (UTC)

hmm interesting[edit] Double sharp (talk) 14:19, 21 September 2015 (UTC)

on Japanese Wikipedia's element-classifying scheme[edit]

Now the greys are called "other metals", and envelope Be, Mg, Zn, Cd, Hg, Cn, as well as our post-transition metals. (I also edited their table to show Mt, Ds, and Rg as "unknown chemical properties", and Fl as a post-transition metal.) So Be and Mg aren't alkaline earth metals there? Interesting.

The inclusion of Be and Mg with group IIB instead of group IIA is quite interesting: I will link again to Jensen's paper on the subject. Now it would be really nice to know what prominent Japanese textbooks say: do they discuss Be and Mg with Ca–Ra or Zn–Hg? (Since German Wikipedia uses Sc/Y/La/Ac like Holleman and Wiberg.) Double sharp (talk) 08:02, 22 September 2015 (UTC)

(Also, beryllium is the only element FA on Japanese Wikipedia. Would be interesting to do that here as well, as it was our first. Also wouldn't mind doing Li and Be together.) Double sharp (talk) 07:34, 22 September 2015 (UTC)

Links please. -DePiep (talk) 22:49, 23 September 2015 (UTC)
Here you go: ja:Template:元素周期表. Double sharp (talk) 02:50, 24 September 2015 (UTC)

I would love to get Fricke/Pyykkö installed there for the extended PT, but I can't write the new overview... Double sharp (talk) 14:02, 26 September 2015 (UTC)

@Sandbh: ja:Template:周期表 has some really interesting border-colour/cell-colour usage for mixed categories (e.g. metalloid/halogen). Double sharp (talk) 12:56, 26 September 2015 (UTC)

If you need graphic effects, please ask. -DePiep (talk) 22:24, 29 September 2015 (UTC)

and one more thing, based on the above mention of Japanese Wikipedia[edit]

Now that we don't use "poor metals", I submit that if we do choose to take group 12 out of the TMs, we'd actually be listened to seriously instead of getting laughed at for "poor metals". If we want to go down that path, that is. (Although it does unfortunately mean uncolouring Cn and Fl. But then the whole can-it-use-d-electrons definition is very unnatural for the superheavy elements, if we listen to the predictions of Fricke et al, as there would be many cases like E113, E165, and E166 where the d electrons are used but result in main-group behaviour.) Double sharp (talk) 08:01, 22 September 2015 (UTC)

eh, getting laughed at for ... is an argument? -DePiep (talk) 22:43, 23 September 2015 (UTC)
Links please. -DePiep (talk) 22:49, 23 September 2015 (UTC)
Let me guess --it's only internet--. :ja:wiki:periodic table? -DePiep (talk) 23:01, 23 September 2015 (UTC)

A discussion on whether to leave group 12 out of the TMs would be worth having, presumably at Template talk:Periodic table. Sandbh (talk) 22:52, 23 September 2015 (UTC)

Emsley's naturally occuring Am, Cm, Bk, and Cf[edit]

If he's right (despite the continuing lack of corroborating papers), the truth is spreading. If he's wrong, we have a funny example of citogenesis, although here at least the fact got printed first. Double sharp (talk) 09:26, 22 September 2015 (UTC)

P.S. A quote from the article: 'Researchers at the Center for Heavy Ion Research (GSI) in Germany, GANIL in France and many others are also working to discover new elements of the periodic table with numbers between 119 and 126. However, the researchers in Dubna believe that’s going to be difficult. "Even though we are building a special accelerator," said Popeko, “most likely element 118 will be the last one discovered because the process is more and more complicated and very expensive."' Q_Q Double sharp (talk) 12:02, 22 September 2015 (UTC)

OK, I've had enough of this impossible-to-verify-outside-Emsley-and-his-source-Walter-Saxon tidbit that's being copied everywhere. I'm going to revert everything back to Pu as the highest natural element, in the absence of corroborating sources outside Emsley. After all, you'd think there'd be papers like there have been for primordial 244Pu. Double sharp (talk) 13:05, 26 September 2015 (UTC)

Yes check.svg Done, mostly. Corrected the most obvious ones; any others can wait a little.
I also edited {{Periodic table}} and one of the others to align La and Ac (the start of the f-block) with the rest of group 3. Two reasons: (1) as Sandbh and I have previously mentioned, Sc/Y/Lu/Lr ... La/Ac shows up best what is going on in group 3, and (2) even if one dislikes the actinide pseudohomology being unclear as to where it ends without further description in the table, the current version suggests Sc/Y/Lu/Lr ... Ce/Th, which is chemically nonsensical as Ce and Th are often (and Th's case, practically always) tetravalent, while the other elements in the column are trivalent. Double sharp (talk) 14:02, 26 September 2015 (UTC)

Wow, it apparently made actual scientists go to check... nope, no news of anything beyond Pu in nature outside Emsley. Double sharp (talk) 02:41, 28 September 2015 (UTC)

This has gone places! Double sharp (talk) 02:56, 28 September 2015 (UTC)

Periodic table no longer periodic with undiscovered elements??[edit]

The article Extended periodic table says:

Elements 1-118 still follow the pattern we know and love. Elements 119 and 120, following the pattern of the first 2 elements of any row, are still following the pattern. But after that, if the elements were to follow the pattern:

  • The g-block (the elements of the eighth row not corresponding to any elements in the higher rows) should have elements 121-138.
  • Elements 139-168 are in the same groups as elements 89-118 respectively.

But the article reveals that the table no longer follows the pattern that we know and love. First, the g-block has 20 elements, not 18. Then, elements 141-164 take the expected positions of elements 139-162. Then there will be no p-block for the eighth row; it will go straight the the s-block of the following row with elements 165 and 166. Worse, the ninth row will be just as long as the second and third rows with just 2 s-block and 6 p-block elements, followed immediately by the g-block of row 10 with no s-block at all. The pattern we all know and love is broken. No more "periodic table", but more of a "groupic table", meaning that putting elements in the same column by group because of their similar properties is what's important, not putting them in periodic patterns. Any thoughts on whether the table really still is periodic?? Georgia guy (talk) 15:33, 22 September 2015 (UTC)

I have an opinion, and I promise to write tomorrow... Double sharp (talk) 15:35, 22 September 2015 (UTC)
You said "write tomorrow", but the "tomorrow" date is now today. Georgia guy (talk) 15:34, 23 September 2015 (UTC)
Take one mor breath, Georgia guy. Or two. -DePiep (talk)

Right. Sorry about that.

Well, periodic table says that it is ordered by atomic number, electron configurations, and recurring chemical properties. No mention of the constant n + ℓ value that you find in every earlier period. So I think it is actually doing its best given the weirdo electron configurations predicted.

Take the extra two superactinides: this is happening because the 8p1/2 electrons are lowered in energy so much that they're filling up along with 5g, and the properties are hard to distinguish. A bad analogy is how not only 4f, but also 5d1 fill up in the lanthanides. It's essentially the same question: "why are there 15 lanthanides when the f-block only can hold 14 elements" and "why are there 20 superactinides when the g-block only can hold 18 elements"?

The difference, of course, is that in the lanthanides 5d is supposed to fill right after they finish, at Lu–Hg, by Aufbau, but in the superactinides 8p should wait till 163–168 by Aufbau. So something has to give, and we, following Fricke, decided to go by predicted chemical properties. 139 and 140 are not expected to act too differently from the other superactinides, so with regards to the table, they should be together. Because when you put elements on the periodic table, there are four steps, per Jensen:

  1. Assign a block based on what electrons are available. For 121–140, g are the main valence electrons, and you can treat the p additions as anomalous.
  2. Assign a group in the block based on how many electrons are available. So we just get twenty columns going in atomic number order.
  3. Verify them by checking if block, group, and periodic trends hold consistently. Given that the superactinides are supposed to be pretty homogeneous, I think we've achieved this.
  4. Verify that the elements are placed in order of increasing atomic number. Yup!

141–164 being two higher than expected is basically because 8p1/2 has also been filled, so you've got an extra two electrons as part of the inert core. So things still work out: for example, Rf has 6d2, and eka-Rf (156) has 7d2, following the above criteria.

Then after that we are faced with a problem. The subshell splitting is such a large effect now that 8p3/2 rises beyond 9s, and so the latter fills first. So we have no choice but to put 165 and 166 in the s-block of the next row. This doesn't really violate the criteria above, as the trends work out. And we have an added bonus that 9p1/2 and 8p3/2 are close in energy, so they act like a single p-subshell. So, why not move 8p3/2 into the ninth row? It keeps the elements in increasing atomic number, fits the trends, and now we have a short period like the 3rd row, just as is predicted by Fricke.

Finally, as for 173–184, since the 9th period is complete at 172, we have to treat it as being the g-block of the next row.

So I think the table is still as periodic as it can get with the electron configuration weirdness. The placements are perhaps not strictly following electron configuration, but do their best to expose the trends, both across periods and down groups. Double sharp (talk) 02:40, 24 September 2015 (UTC)

I suggest that more research on the properties of francium astatinide, which is based on the known periodic table, may be in order. I will explain that more tomorrow. Robert McClenon (talk) 16:36, 23 September 2015 (UTC)
The periodic table has to do with chemistry, not physics (except to the extent that chemistry is physics). The periodic table is a mechanism for organizing the elements based on their chemical properties. If an element doesn't exist long enough to have falsifiable chemical properties, its placement in an extended periodic table and the shape of the extended periodic table are untestable, not even wrong. Francium and astatine are both known, naturally occurring trace elements as products of the three radioactive decay sequences, and its chemistry is not even well known, when each of its elements has a half-life of minutes, not milliseconds, and francium and astatine are in their proper places in the regular periodic table. An extended periodic table for elements whose half-lives are so short that their chemistry is not testable is operationally meaningless. Robert McClenon (talk) 16:07, 25 September 2015 (UTC)
Except that they are predicted to have stable-enough isotopes for chemistry, thanks to islands of stability around E122 and E164. So this table is a prediction, and would probably be falsifiable if we made those elements. So you could think of it as just a guide, a starting point to future chemical studies, using physics as a guide to make first extrapolations of chemistry into this large unknown area of the periodic table.
Fr's chemistry is known, just uninteresting (only Fr+). As for astatine, there's enough to write a whole section at Astatine#Compounds. Even flerovium, with investigated isotopes having half-lives in the milliseconds, has been chemically experimented on (Flerovium#Experimental chemistry). And we even have a preliminary experimental value for the boiling point of copernicium (maximum half-life of half a minute). So I would certainly not rule out chemical experimentation techniques developing to the point that it can handle millisecond-isotopes in the near future. There are already studies thinking about chemically investigating elements up to Lv, with a 61-millisecond half-life! Double sharp (talk) 05:58, 26 September 2015 (UTC)
Finally, we already put elements like meitnerium on the periodic table, even though their chemistry has not yet been tested at all. (It could be: there's an eight-second isotope, but it's just that no one has gotten around to it.) For now, it's placed below Ir because it's expected to behave like Ir, but we don't know yet. So it seems there is already precedent for making tentative placements on the periodic table based on predicted chemical properties. Double sharp (talk) 05:52, 26 September 2015 (UTC)