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WikiProject Elements (Rated Project-class)
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Element news[edit]

Although List of oxidation states of the elements shows the +2 state as being known since 1966?
From that article: "The new +2 oxidation state, sought for over 30 years, has been seen fleetingly in the gas phase but until now it has not been observed in molecular species in solution." Double sharp (talk) 13:22, 25 October 2014 (UTC)
Any chance we can get a level Langmuir figure? The one that's there at the moment slopes up to the right. Sandbh (talk) 00:07, 26 October 2014 (UTC)
But only a cation, so far
Added to list of oxidation states of the elements and iridium. Double sharp (talk) 13:40, 25 October 2014 (UTC)

Sandbh (talk) 03:16, 25 October 2014 (UTC)

List of metalloid lists maintenance[edit]

In the list, I noticed an repetition of authors (interesting: did they change their list?). And the list has stopped after 2011. See Talk:List_of_metalloid_lists#Wandering_authors. "We" can take a few months to check & improve the list, and then do the recalculations once. Please continue overthere, and enjoy this. @Sandbh: -DePiep (talk) 00:27, 9 November 2014 (UTC)

Polonium and astatine as metalloids or as ptm's?[edit]

Periodic table (polyatomic).svg
Periodic table (metalloids).png

At the moment, we have two articles periodic table Cscr-featured.png and metalloids Cscr-featured.png conflicting about the categorization of polonium and astatine. They are variously in 'post-transition metal' or 'metalloid'. Maybe we can put these elements in the same category (both post-transition metal or both metalloid), well reasoned.


Background

In our general periodic table graphs, Po is post-transition metal/grey and At is metalloid/brown. Polonium: was part of the wide discussion in 2012: WT:ELEMENTS, Archive 15. Astatine: in 2013, we decided to remove "halogen" category (which, before, forced At to be categorized halogen because of the halogen group). This allowed us to mark astatine 'metalloid/brown'.

In the 2014 article metalloid, polonium and astatine are classified together (strongly together I can say) as "Irregularly [named as metalloid] (44% [light blue]): Po, At", based on the 194-sources frequency. I remember that the periodic table graph was removed from the metalloid article content in FAR process, because this discrepancy could not be addressed (it still is there in the footer navbox, which is non-content btw).

Quest

I think we could reconsider the situation, and bring both categorizations in line. The graphs then follow.

  • Set Po and At, both, in category & coloring into "metalloid/brown" or
  • Set Po and At, both, in category & coloring into "post-transition metal/grey"

Notes:

  1. As always with these category-border issues, in the individual articles (like polonium, astatine, metalloid, post-transition metal) the peculiarities and exceptions can be described in detail.
  2. Prevent a complexity: the three leapfrogging discussions in the histories can introduce complexities (in hindsight, arguments & conclusions are interacting between years). I strongly suggest to start thinking forward only, starting with the situation as it is today. Older arguments can be repeated here of course, but the old conclusions would create a headache.

-DePiep (talk) 11:53, 10 November 2014 (UTC)

I think Po is too much like a metal to be called a metalloid at all. Its behaviour is normal for a metal: perhaps its anions are more stable than most metals, but this is because it is so close to the right end of the periodic table. But At's metalloid properties are strong enough that I think it's not so good to call it a metal. It still has the narrow liquid range and nonmetallish band gap, likes to form anions in aqueous solution, and its closest relative is iodine, a nonmetal (with incipient metallic properties, for sure, but I wouldn't even call iodine a metalloid). So I think in general, it's best to call Po a metal and At a metalloid, and talk about the category border issues in the individual articles.
Remember, the figure at the top of the metalloid article is about how common it is for the relevant elements to be called metalloids. Our own categorization does not have to follow that. Nevertheless, I think that figure should remain at the top of the metalloid article – because it brings the point home that the category is fuzzy and is demarcated differently by different texts. Double sharp (talk) 13:58, 10 November 2014 (UTC)
The periodic table illustration categorizes elements into metal/metaloid/nonmetal, but the metaloid illustration does quite a different thing, showing the frequency which various sources list elements as metaloids. If that frequency data were all we had, it might make sense for us to consider the top cluster or two to be metaloids. But as Double Sharp mentions, this is not our only data. But even if it were our only data, I still think it would be suspect to include the second cluster (Po+At), as the references are rather consistent. In fact, the correlation coefficient is only about 20%. So although the scores for Po and At (48% and 40%) are relatively close to each other and relatively distant from the next higher (B, 86%) and next lower (Se, 24%) scores, the internal inconsistency between the references leads me to disagree with DePiep's statement that Po and At are clustered 'strongly' together in List of metalloid lists. Here is a tabular representation of the non-correlation between attestations of Po's metaloidicity and At's metaloidicity.
Raw Scores
At metaloid At# marginal At non-metaloid
Po metaloid 44 refs 3 refs 44 refs
Po# marginal 1 ref 3 refs 1 ref
Po non-metaloid 30 refs 0 refs 68 refs
Weighted Scores
At metaloid At non-metaloid
Po metaloid 46.75 refs (24%) 46.75 refs (24%)
Po non-metaloid 31.25 refs (16%) 69.25 refs (36%)
In short, I think the status quo is just fine. YBG (talk) 22:17, 11 November 2014 (UTC)
Some quick notes first.
When I said 'strongly together', I meant exactly the statistics you describe: close together, far away from the others. For now, no comment on the more detailed tables you added.
Indeed these are not the only data we have, and then we only use their numbers, not their quality of argument. My question rose from this: when the sources mention them in ~equal numbers, why are they split so definitively in our PT graph? It is wqhat I'm trying to get my head around. Clearly, I am not trying to prove one 'wrong'.
re Double Sharp: the first half reads like the #195th source in that List of metalloid Lists. FWIW, 30/194 sources too mention At not Po as metalloid; but the non-correlation tables by YBG say more I don't understand yet. -DePiep (talk) 03:04, 12 November 2014 (UTC)
Shouldn't it be "69.25 (36%)"? And then, doesn't that say that the diagonal to pair them (both are/none are) is more convincing? -DePiep (talk) 03:12, 12 November 2014 (UTC)

──────────────────────────────────────────────────────────────────────────────────────────────────── "When the sources mention them in ~equal numbers, why are they split so definitively in our PT graph?"

Well, the sources are roughly 50:50 on Po and At, as to whether either of them are metalloids. We had to make a decision which way to go in our periodic table graph. Given what the literature says about the properties of Po and At (which is mostly summarized in the metalloid article, we decided Po = post-transition metal; At = metalloid. Astatine might conceivably be a post-transition metal, on the basis of the 2014 relativistic modelling article, but few people would be brave enough to make that call without corroboration. Given the incipient metallic character of iodine, it seems reasonable to at least classify astatine as a metalloid on the basis of periodic trends. Sandbh (talk) 11:02, 13 November 2014 (UTC)

Thanks, DePiep for catching my error! I have corrected the chart above. The point is that 60% are on the diagonal and 40% are off the diagonal, which may be a correlation, but a fairly weak one: almost as many sources disagree about Po+At (40%) as agree about them (60%). By the way, if there were absolutely no correlation between what the sources think about At and what they think about Po, this is what you would expect
Expected results if the sources opinion about At and Po were completely independent
At metaloid At non-metaloid
Po metaloid 37.25 refs (19%) 55.87 refs (29%)
Po non-metaloid 40.35 refs (21%) 60.53 refs (31%)
My point is that the sources opinions about At and their opinions about Po are very weakly correlated. The on-diagonal values are only slightly more (and the off-diagonal values only slightly less) than one would expect with no correlation at all. Based on this, it doesn't surprise me that we would wind up classifying Po and At differently. YBG (talk) 07:33, 14 November 2014 (UTC)
All I did was showing (off) that I have read your post, and now you punish me with more statistics? ;-) Later more. -DePiep (talk) 07:45, 14 November 2014 (UTC)
No good deed goes unpunished ;-) YBG (talk) 08:00, 14 November 2014 (UTC)
"Chemistry for Dummies" states that Po is a metal- that settles it.Axiosaurus (talk) 16:59, 14 November 2014 (UTC)
Here's my go at attempting to confirm the wisdom of Dummies with some observations from the literature. 1. All elements that unambiguously form simple cations in aqueous solution are classified as metals. 2. Polonium does this too, forming the pink Po+2 ion in dilute hydrochloric. 3. Polonium doesn't exhibit much nonmetallic chemistry. 4. There are no arguments in the literature, that I'm aware of or can recall, making a case for classifying polonium as a metalloid. These four observations warrant classifying polonium as a metal.
A potential wrinkle in the above is that astatine is thought to be able to form an At+ cation in strongly acidic aqueous solution, noting its chemistry is clouded by the uncertainties of trace level experiments. It has also been predicted to have a metallic band structure---a genuine one, not that of a semi-metal, like As, Sb and Bi. If both of these statements turn out to be true, then astatine ought to be classified as a post-transition metal, i.e. a metal characterized by significant non-metallic character. Until more data is in, classifying astatine as a metalloid---as per Dummies---seems appropriate.
Incidentally, there is a review of Chemistry for Dummies, in Chemistry in Australia, here (p. 37). Sandbh (talk) 01:27, 17 December 2014 (UTC)

Merge proposal of two large-cell PT articles[edit]

Merge-arrows.svg Articles Periodic table (large version) and Wide periodic table (large version) are proposed for a merge. Proposal and discussion is here. -DePiep (talk) 14:17, 12 November 2014 (UTC)

Yes check.svg Done. See periodic table (large cells) (moved). -DePiep (talk) 12:13, 23 November 2014 (UTC)

TfD for Infobox_elements 121, 124, 126[edit]

Three unused element infoboxes are up for deletion. See this TfD. -DePiep (talk) 15:46, 12 November 2014 (UTC)

Deleted. -DePiep (talk) 12:13, 23 November 2014 (UTC)

Your input is requested[edit]

There seems to be what could easily turn into an edit war over at Periodic table (large cells). I've asked the two editors involved to list their differences here so that others can weigh in. YBG (talk) 07:22, 25 November 2014 (UTC)

Yeah, but it's no big deal. -DePiep (talk) 12:01, 25 November 2014 (UTC)

Chinese periodic tables[edit]

These templates have been nominated for deletion. See Wikipedia:Templates for discussion#Chinese periodic tables for the discussion.--JohnBlackburnewordsdeeds 18:22, 4 December 2014 (UTC)