Talk:Periodic table

On the issue of numbering the shells of the layers of the electron cloud of atoms

In my opinion, it would be better to start the shell number of the electron cloud layer of the atom l not from zero, but from one. After all, the number of shells in a layer is equal to the layer number. The tradition of numbering shells from scratch, inherited from the beginning of the 19th century, is in contradiction with logically understandable numbering: 1, 2, 3, 4, 5, ... The number zero can be perceived as the absence of what is numbered in natural numbers. Alex makeyev (talk) 21:50, 9 February 2024 (UTC)

We can interpret the reason for the properties of halogen in hydrogen and the properties of noble gas in helium in this way. The missing p-shell in the first layer of the electron cloud of hydrogen and helium atoms is replaced by its s-shell for two finite elements of the virtual p-shell. Alex makeyev (talk) 05:50, 14 March 2024 (UTC)

Janet's left-step table: Irregularity

@Double sharp: And any other interested editor.

The text in the Alternative Periodic Tables section currently reads, in part:

Janet's left-step table is being increasingly discussed as a candidate for being the optimal or most fundamental form; Scerri has written in support of it, as it clarifies helium's nature as an s-block element, increases regularity by having all period lengths repeated...

I added a footnote after "repeated" saying:

"That said, the left-step table introduces a new irregularity, not present in the traditional form of periodic table, in that the sequence of shell numbers at the start of each period is 1, 2, 2, 3, 3, 4, 4... i.e. the sequence is duplicated in all cases but the first."

You reverted this addition on the grounds of no citation being applied.

Could you clarify your position? The fact that the LSTP has an irregular sequence of shell number starts is evident from a simple counting of the numbers shown in the margin on the left side of the LSTP in the immediately following LSTP in the article. Here it is again:

Left-step periodic table (by Charles Janet)

f1

f2

f3

f4

f5

f6

f7

f8

f9

f10

f11

f12

f13

f14

d1

d2

d3

d4

d5

d6

d7

d8

d9

d10

p1

p2

p3

p4

p5

p6

s1

s2

1s

H

He

2s

Li

Be

2p 3s

B

C

N

O

F

Ne

Na

Mg

3p 4s

Al

Si

P

S

Cl

Ar

K

Ca

3d 4p 5s

Sc

Ti

V

Cr

Mn

Fe

Co

Ni

Cu

Zn

Ga

Ge

As

Se

Br

Kr

Rb

Sr

4d 5p 6s

Y

Zr

Nb

Mo

Tc

Ru

Rh

Pd

Ag

Cd

In

Sn

Sb

Te

I

Xe

Cs

Ba

4f 5d 6p 7s

La

Ce

Pr

Nd

Pm

Sm

Eu

Gd

Tb

Dy

Ho

Er

Tm

Yb

Lu

Hf

Ta

W

Re

Os

Ir

Pt

Au

Hg

Tl

Pb

Bi

Po

At

Rn

Fr

Ra

5f 6d 7p 8s

Ac

Th

Pa

U

Np

Pu

Am

Cm

Bk

Cf

Es

Fm

Md

No

Lr

Rf

Db

Sg

Bh

Hs

Mt

Ds

Rg

Cn

Nh

Fl

Mc

Lv

Ts

Og

Uue

Ubn

f-block

d-block

p-block

s-block

This form of periodic table is congruent with the order in which electron shells are ideally filled according to the Madelung rule, as shown in the accompanying sequence in the left margin (read from top to bottom, left to right). The experimentally determined ground-state electron configurations of the elements differ from the configurations predicted by the Madelung rule in twenty instances, but the Madelung-predicted configurations are always at least close to the ground state. The last two elements shown, elements 119 and 120, have not yet been synthesized.

I had thought that a simple counting of numbers, as 1, 2, 2, 3, 3, 4, 4, 5 etc would not need a supporting citation.

Thank you. Sandbh (talk) 12:03, 7 February 2024 (UTC)

@Sandbh: The issue at stake, that requires a citation, is whether anyone else considers this an irregularity or even an important desideratum for periodic tables. One could list any number of numerological regularities or irregularities in the standard table as well, such as the fact that Fibonacci-numbered elements always start half-rows of blocks until the pattern breaks down at 144. But even though they are obviously evident from counting, saying it is a regularity or irregularity requires a source. This is pretty much a textbook case of WP:SYNTH: conclusions drawn (i.e. in this case the idea that this is a significant irregularity that counters Scerri's statement) must be in some RS.

Also note that it would be mathematically impossible for 1 to occur twice, as there is only one subshell with n = 1: 1s. Therefore, there is even a clear reason to doubt the relevance of the irregularity. Double sharp (talk) 12:12, 7 February 2024 (UTC)

The reason that numbers are repeated is that each odd numbered row begins with the same number as the preceding even numbered row. The first odd numbered row (#1) has no preceding even numbered row (#0) to match. Hence, the irregularity being noticed is logically equivalent to saying that the first row is the only row that lacks a predecessor, an anomaly that the traditional PT shares. YBG (talk) 22:34, 7 February 2024 (UTC)

More to the point, the Janet table doesn't really care about n. That's not its job. It cares about n + ℓ. doi:10.1002/qua.965 outright mentions that it replaces n rows with n + ℓ rows (footnote on p. 83). So it's about like asking why the usual PT has a bunch of columns where the group oxidation state can never be reached: that is no longer the point, so it is not a legitimate reason to criticise it. That would well explain why nobody seems to have made this criticism in the literature. Double sharp (talk) 03:09, 8 February 2024 (UTC)

@Double sharp and YBG: Scerri's dislike of the conventional periodic table (CPT) is well-known, and focuses on its irregular period lengths—2, 8, 8, 18, 18, 32, 32—highlighting the non-repetition of the initial length of 2 as a significant irregularity. In contrast, he advocates for the left-step periodic table (LSPT) due to its uniform period lengths: 2, 2, 8, 8, 18, 18, 32, 32, presenting this regularity as a rectification of the CPT's flaw.

However, what Scerri overlooks is a distinct irregularity introduced by the LSPT, absent in the CPT. Specifically, the LSPT's sequence of principal quantum numbers (n) at the start of each period shifts to 1, 2, 2, 3, 3, etc., diverging from the CPT's orderly progression of 1, 2, 3, 4, 5, 6, 7. This modification results in a scenario where the n value of 1 does not recur, contrasting with the consistent sequence observed in the CPT.

This particular irregularity is readily observable through simple counting, directly from the table's presentation within the article.

Discussing the sequence of n values in periodic tables, such as the CPT and the LSPT, by pointing out the n values through straightforward counting of elements or positions on the table constitutes a factual observation. It does not constitute synthesizing new conclusions from multiple sources or introducing original theories; rather, it is a direct observation and report on the structure as depicted in the table. Thus, it does not fall within WP:SYNTH, since it aligns with WP:CALC.

The footnote regarding the LSPT is not a critique based on mathematical impossibilities, nor does it seek to draw parallels with anomalies in the CPT or to question the LSPT's priorities. The aim is to ensure a balanced perspective on the LSPT by noting that, effectively, while it corrects one irregularity of the CPT, it introduces another concerning the sequence of n values.

This insight is vital for an understanding of the periodic table's design, underscoring the importance of evaluating both the strengths and limitations of models like the LSPT. By being exposed to these details, readers are better equipped to grasp the complexities involved in accurately and effectively representing elemental properties and behaviors. The intention is not to undermine the LSPT's value but to promote a holistic examination of its contributions and the challenges it presents within the context of periodic table design. --- Sandbh (talk) 12:03, 9 February 2024 (UTC)

@Sandbh: So, give us a cite saying that that's important. Otherwise, how do we know that it's a relevant critique, especially when we have an RS pointing out that LSPT is not really based on n at all? Double sharp (talk) 12:13, 9 February 2024 (UTC)

@Double sharp and YBG: I don't have a citation about the irregularity of n values at the start of periods in the LSPT. The quite limited literature on the LSPT appears to focus on the regularity of its period lengths, and attempts to jusify He over Be. However, a citation may not be strictly necessary. WP:NOTCITE discusses instances where a source or citation might not be required, offering examples of general common knowledge, such as "The capital of France is Paris" or "Humans normally have two arms and two legs." While WP:NOTCITE is an explanatory essay rather than an official policy or guideline, its substance is instructive.

That the LSPT is based on n + l does not mitigate the introduction of a new irregularity namely that the values of n at the start of each row now become irregular, unlike the regular values of n at the start of the CPT. This new irregularity is a direct consenquence of the LSPT's foundational principle based on n + l.

This irregularity in the LSPT, while not constituting "common knowledge" in the broadest sense, is a straightforward observation about the table's structure, verifiable by anyone through direct examination.

Aligning with the WP commitment to accuracy and comprehensiveness, such factual observations—especially those that can be directly verified without the need for specialized knowledge or interpretation—significantly contribute to our collective understanding. Including this detail offers a more comprehensive, nuanced, and balanced view of the LSPT's design, adhering to the spirit of Wikipedia's standards for verifiability and reliability. Sandbh (talk) 11:30, 10 February 2024 (UTC)

@Sandbh: So, you don't have a cite, and you admit that most sources discussing LSPT don't focus on this. Therefore, it seems to be in the same situation as the Fibonacci-atomic-number example, and the source-based case for putting it into the article hasn't been made. Double sharp (talk) 11:36, 10 February 2024 (UTC)

@Double sharp and YBG: The Fib example, while interesting, isn't relevant to our discussion on the LSPT's structural irregularity. The focus is on a specific, observable difference in the regulariy of n values between the LSPT and the CPT, not abstract patterns. This irregularity, directly observable and verifiable by examining the image of the LSPT, impacts the understanding of its organizational principles compared to the CPT.

I've addressed the lack of a source via WP:NOCITE.

WP:PRIMARY allows the use of primary sources for straightforward, descriptive statements that can be directly observed. The argument about the LSPT's n values could be considered a use of the LSPT itself as a primary source for a descriptive observation.

WP:FACTS aka WP:BLUESKY is also relevant, as is WP:NOTBLUESKY. Reconciling the two, I suggest, supports the use of editorial discretion in achieving a balance between the rigorous application of the verifiability principle and the practical considerations of contributing to an encyclopedia that is both informative and accessible.

WP:COMMONSENSE encourages editors to use common sense and occasional exceptions when interpreting and applying Wikipedia's rules. The inclusion of this observation would significantly contribute to the article's accuracy and completeness without straying into original research (as I've previously explained). --- Sandbh (talk) 06:41, 11 February 2024 (UTC)

(outdent)

@Sandbh: Concerning this info about the sequence of n values, we need to consider several aspects:

1. Is it true? (I say Yes, and I believe you agree.)
2. Is it mentioned in RS? (I say No, and I believe you agree.)
3. Are RS required to verify its truth? (I say No, and I believe you agree.)
4. Is it significant? (I say No, but I believe you disagree.)
5. Is its significance mentioned in RS? (I say No, and I believe you agree.)
6. Are RS needed to verify its significance? (I say Yes, but it appears you disagree.)

WP:RS says:

[W]e publish only the analysis, views, and opinions of reliable authors, and not those of Wikipedians who have read and interpreted primary source material for themselves.

And:

Wikipedia articles should be based on reliable, published sources, making sure that all majority and significant minority views that have appeared in those sources are covered.

This irregularity seems to have been noticed in exactly zero RS, so it falls short of being a significant minority view in terms of significance (though not of truth).

In this post, I have not sought to convince you that this irregularity is insignificant, merely that its significance is insufficiently attested for inclusion in WP. Nevertheless, if you show from RS that a significant minority think this irregularity is significant, I will support its inclusion, even if I remain unconvinced of its significance.

——— YBG (talk) 20:30, 10 February 2024 (UTC)

@YBG: Thanks. I believe these matters have been addressed in my reply to Double sharp concerning WP policy. For the record, I concur with 1, 2, 3, and 5. For #4 and #6 it certainly is significant given the LSPT literature's zeal about the regularity of the LSPT. It represents a case of significance by omission. --- Sandbh (talk) 06:53, 11 February 2024 (UTC)

@Sandbh: That the sequence of n is 1,2,2,3,3,4,4,… is obvious. But saying this is a LSPT flaw is not just describing, it is interpreting. Your interpretation, your opinion, is not shared by @Double sharp and I, nor, so far as you have shown, by any RS. Paraphrasing WP:RS, we do not publish the opinions … of Wikipedians who have … interpreted [facts] for themselves. Yes, the sky is blue, but to say that the blue sky is soothing or beautiful or ugly or whatever, you need RS. Let’s discuss this further when you find a RS.

———- YBG (talk) 22:27, 11 February 2024 (UTC)

@Sandbh: I agree with YBG. Double sharp (talk) 12:08, 12 February 2024 (UTC)

@YBG and Double sharp: Thanks. YBG, where you wrote, "But saying this is a LSPT flaw", is ascribing something to me—that this is a "flaw"—that I have never written. That would certainly be an opinion or interpretation. OTOH, saying that the sequence 1,2,2,3,3,4,4,… is irregular, is obvious, in the same way that the sequence of n (as you put it) is 1,2,2,3,3,4,4,… is a statement of the obvious.

What's more, I've noted that mentioning the irregular sequence is accommodated within WP:CALC, WP:NOCITE; WP:PRIMARY; WP:BLUESKY and WP:NOTBLUESKY, and WP:COMMONSENSE.

The current situation is analogous to an unacknowledged elephant in the room, which is poor showing for an encyclopedia. Per WP:PRINCIPLE, Editors must also consider the rules in the broader context of the wiki editorial process and the goal of improving Wikipedia.

If it helps I would slightly change the footnote to refer to an "irregular sequence" rather than a "new irregulariy", as follows:

"That said, the left-step table has an irregular sequence, not present in the traditional form of periodic table, in that the progression of shell numbers at the start of each period is 1, 2, 2, 3, 3, 4, 4... i.e. the sequence is duplicated in all cases but the first."

--- Sandbh (talk) 01:36, 16 February 2024 (UTC)

If it were really so important as to be called an elephant in the room, then don't you think some RS would've mentioned it? Double sharp (talk) 14:23, 16 February 2024 (UTC)

@Double sharp: Thanks. No, because the literature in this area is very limited and focuses on discussing the positive aspects of the LSPT e.g. that all elements in a period have an n+l value equal to the period number, unlike the conventional PT. Even so, this comes at the expense of irregularising the sequence of n numbers at the start of each period. It is like a game of Whac-a-mole. Fix one irregularity and another one pops up to take its place. This creates a gap in coverage, hence the expression, "unacknowledged elephant in the room". Addressing this gap aligns with Wikipedia's goal of creating a better encyclopedia. Sandbh (talk) 07:18, 19 February 2024 (UTC)

@Sandbh: In my previous post, I tried to demonstrate that this opinion (the irregularity in the sequence of n is a significant as a flaw in the LSPT). If you wish to comment on that from the WP policy angle, please reply to that thread.

In this thread, I would like to discuss not the WP angle, but the significance angle. I will do this by asking you to look at the conventional PT (CPT).

Let us examine the sequence of primary quantum numbers in the CPT. On the left side and the right side, this number increases regularly 1,2,3,4,…. It also increases regularly in each of the blocks (s,p,d,f,…). The CPT and LSPT share the right-side regularity and the per-block regularity, just not the left-side one.

However, one of the features of the CPT is that the leftmost and rightmost columns columns are full top-to-bottom with a gap in the middle. Let us consider the progression of n in the elements immediately before and immediately after CPT’s characteristic gap after opening the gap to make space for additional blocks f,g,h,….

To the left, we see a regular progression 1,2,3,4…. To the right, we see an irregular progression 1,2,2,3,3,4,4,….

Is this a significant irregularity in the CPT? No, it is simply an artifact of where the CPT places the stair step. And this is exactly why the same irregularity appears on the left side of the LSPT.

So the 1,2,2,3,3,… irregularity you noticed appears in both the LSPT and that CPT. The two tables simply position the irregularity differently.

As I said, if you wish to interact about WP policy, please respond to the other thread. If you wish to discuss the significance of the irregularity, respond to this thread.

——— YBG (talk) 21:10, 10 February 2024 (UTC)

@YBG: Thanks. This observation is irrelevant since the issue is only to do with the regularity of n values at the start of a period. In the CPT the sequence is 1, 2, 3, 4, 5, 6, 7. In the LSPT the sequence is 1, 2, 2, 3, 3, 4, 4. The LSPT thus introduces an irregularity not present in the CPT. @Double sharp: FYI. --- Sandbh (talk) 05:17, 11 February 2024 (UTC)

Ok, I’ve failed to convince you. But it was worth a try, just as your unsuccessful attempt to convince me was worth the try. YBG (talk) 06:16, 11 February 2024 (UTC)

@YBG: I've just posted a reply to Double sharp concerning WP policy. Sandbh (talk) 06:43, 11 February 2024 (UTC)

My periodic table breakdown

Alkali metals - Li, Na, K, Rb, Cs, Fr

Alkaline earth metals - Be, Mg, Ca, Sr, Ba, Ra

F-block (lanthanides and actinides) - La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Ac, Th, Pa, U, Np, Pu, Am, Cm, Bk, Cf, Es, Fm, Md, No

Transition metals - Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Cd, Lu, Hf, Ta, W, Re, Os, Ir, Pt, Au, Hg, Lr, Rf, Db, Sg, Bh, Hs, Mt, Ds, Rg, Cn

Post-transition metals - Al, Ga, In, Sn, Tl, Pb, Bi, Nh, Fl, Mc, Lv, Ts

Metalloids - B, Si, Ge, As, Sb, Te, Po

Other nonmetals (including halogens) - H, C, N, O, F, P, S, Cl, Se, Br, I, At

Noble gases - He, Ne, Ar, Kr, Xe, Rn, Og

TheCool1Z (talk) 23:58, 21 February 2024 (UTC)

This is essentially no different to the breakdown shown in the Classification of elements section. — Sandbh (talk) 00:19, 3 March 2024 (UTC)

Strange lede sentence

Is it just me, or is it a bit strange to have the lede sentence describe the subject in a verb form (the periodic table arranges) instead of a noun form (the periodic table is an arrangement)? 

I propose that the lede sentence should be changed to: The periodic table, also known as the periodic table of the elements, is an ordered arrangement of the chemical elements into rows ("periods") and columns ("groups").

Sincerely,✨ΩmegaMantis✨^blather 21:36, 2 March 2024 (UTC)

@OmegaMantis: Feel free to make it so. — Sandbh (talk) 23:10, 2 March 2024 (UTC)

Ns

What is the horizons are called In the periodic 41.116.7.2 (talk) 15:43, 17 April 2024 (UTC)