Talk:Mendeleev's predicted elements

From Wikipedia, the free encyclopedia

Contents

[edit] Consolidation of 3 articles

This page's article, like Ekaboron and Ekaaluminium, was formerly a redir to the corresponding modern element name. The current articles could almost be written as parameterizations of a single template, and also bcz of their subject-terminologies' brief currency and intimate relationship (note the existing net of cross refs), they can be treated efficiently (not just as to space, but also as to link-following saved on the part of users who are likely to be interested in all 3 eka-elements if they are interested in one). The Es one has an extra feature, so it is my choice for the one to rename and add the content of the others to, to serve there as stubs for their respective sections.
(I do not propose to merge the histories, since that is practically irreversible, and there will be no significant additional history concealed in the redirects' history pages.)
--Jerzy (t) 21:42, 2005 Mar 29 (UTC)

As the original author of the three articles, I have no objections to the consolidation.

--165.247.187.131 23:57, 30 Mar 2005 (UTC)

[edit] Symbols

I replaced Ea by El, matching Gordin's (p. 39) direct quote from DM's 1875 Comtes Rendus article, in the absence of knowing a contrary source for "Ea". --Jerzy (t) 22:50, 2005 Mar 29 (UTC)
Someone has changed back from El to Ea, I helped you to correct again (change Ea to El). 195.239.158.54 18:05, 18 July 2006 (UTC)

[edit] Additional Predictions

I've come across eka-manganese and dvi-manganese (as place-holders for technetium and rhenium), with attribution to Mendeleev, but not anything solid to support the attribution, nor with symbols attached. There are also a bunch of other eka's and dvi's out there, but they seem to be inspired by the Mendeleev example rather than actually predicted by Mendeleev. This is especially evident in the case of eka-rhenium, which if had come from him, would likely have been tri-manganese! Anyway, include these two now, or wait for more support?
--165.247.187.131 23:57, 30 Mar 2005 (UTC)

Gordin's bio mentions only the three, so i would be skeptical about even the two more, and want them traced back to scholarly sources. I think my inference of "3 and no more" is rebuttable, but not by a few Web sites that cite no sources.
Googling, the article The Chemist and the Grammarian suggests what this may be about: the references can support the bottom 5/8 of (Kak's!) table 3 only in the sense that (DM's) table 2 has dashes in the right places. The stub doesn't make clear what these DM's predictions are: not just "there's room for another element" but quantitative specifications of the properties those elements will have, much more detailed than the little table in the Ge section. It might be good to append one section to the existing ones, noting that in theory additional "predictions" could have been made, but IIRC, the deeper down the table you go, the more similar adjacent groups' elements become, and thus the less significant (the less relatively precise) the predictions can be. I'll be surprised if there are more that deserve the same role in the article that the three do.

--Jerzy (t) 02:30, 2005 Apr 2 (UTC)

I've come across another article via Google that is in Korean [1] that mentions the same names. I think I’ve seen enough evidence to argue in favor of adding eka-manganese (aka technetium) to the article with a predicted atomic weight of 100 to the article. However, I have seen no evidence no evidence that a possible symbol of Em was used.
As for the rest, while the cited Korean article gives predicted atomic weights: Eka-niobium and eka-caesium were at best predictions that failed due to the lack of knowledge of the rare earths at the time. Tri-manganese, dvi-tellurium, and dvi-caesium may well have suggested by Mendeleev, and possibly renamed dvi-manganese, eka-tellurium, and eka-caesium once it was better understood how many rare earth elements there were, but need more support before being added to the main article. The case for eka-tantalum seems to be a hybrid of the one for eka-manganese and eka-niobium.
Perhaps adding some text explaining the origin and meaning of the eka-, dvi-, and tri- prefixes and mentioning that they have been used by Medeleev and others for other projected elements would be sufficient? I think I’ll do an edit of the article along those lines.

--165.247.190.175 21:54, 5 Apr 2005 (UTC)

Just finished the edit, altho I added some of the details concerning the prefixes to the existing article for eka.

--165.247.190.175 23:04, 5 Apr 2005 (UTC)

Arrgh! Just noriced that the technetium article links together Mendeleev's ekamanganese and technetium. I'm going to go ahead and add this to this article.

--165.247.190.175 23:09, 5 Apr 2005 (UTC)

[edit] Zero Group / Ether

Robert Neil Boyd's November 6, 2006 edit of two orginal paragraphs seems based on a unmoderated post he made himself on http://forum.physorg.com/index.php?showtopic=374&view=findpost&p=140276 and has no cited references. The date of 1904 is in question, as the less-than scholarly http://www.rexresearch.com/ether/mendelev.htm says 1902. 12.178.36.25 01:03, 9 November 2006 (UTC)

Confirmed. Written 1902, (self-?) published 1903, published in English, 1904 12.178.36.25 19:58, 9 November 2006 (UTC)

http://www.spbu.ru/Structure/Culture/Museums/Mendeleev/enhist.html suggests that Mendeleev's ether was ONE element, not several.

It was not in the first publication, not the 1869 draft table http://www.chemheritage.org/EducationalServices/chemach/ppt/lm01.html Not in the On the Relationship of the Properties of the Elements to their Atomic Weights D. Mendelejeff, Zeitscrift für Chemie 12, 405-406 (1869); translation by Carmen Giunta http://web.lemoyne.edu/~giunta/EA/MENDELEEVann.HTML and not in 1889 http://web.lemoyne.edu/~giunta/EA/MENDELann.HTML

Indeed, the earliest publications of the periodic table omit all the inert gases, leaving no space for an inert "element zero"

I think Nature, 430 page 7002 might have corroboration of Mendeleev's views over time.

12.178.36.25 01:03, 9 November 2006 (UTC)

Date of "ether" now correctly attributed to 1902-1903 -- after acceptance of Helium and Argon. With citations. 12.178.36.25 19:58, 9 November 2006 (UTC)
Nature article is just a book review, but by one of the sources cited now on the main page.

Bensaude-Vincent, Bernadette (19 August 2004). "A struggle for order". Nature 430 (7002): 834. doi:10.1038/430834b.  based on Gordin, Michael D. (2004). A Well-Ordered Thing: Dmitrii Mendeleev and the Shadow of the Periodic Table. New York: Basic Books. ISBN 0-465-02775-X.  12.178.36.25 22:27, 9 November 2006 (UTC)

[edit] Tc-98

I don't think this is right.

98Tc has an atomic mass of 97.907215.

98Tc would have an atomic mass of 98. Single isotopes cannot have a fractional mass. The fractional atomic mass is because of a mixture of isotopes so Tc-98 is really a mix of Tc-98 and lighter masses together.

No, don't worry about it - only Carbon 12 is supposed to be right on the money - otherwise, mass defects are not regular and proton:neutron ratio bungs it up a little too WilyD 14:08, 10 July 2006 (UTC)

[edit] Removed refs

User:JzG removal edit

item: |location=New York|url=http://www.rexresearch.com/ether/mendelev.htm

full cite
cite book|
last=Mendeléeff|
first=D.|
authorlink=Dmitri Mendeleev|
editor=G. Kamensky (translator)|
title=An Attempt Towards A Chemical Conception Of The Ether|
publisher=Longmans, Green & Co.|
date=1904|
location=New York|
url=http://www.rexresearch.com/ether/mendelev.htm

J. D. Redding 22:48, 11 April 2007 (UTC)


[edit] on sorting elements according to weight

A reader asked an interesting question about this article in Wikipedia:Reference_desk/Archives/Science/2007_October_3#Confirm_vs_define I havn't found mention in the articles about Mendeleev and the period table of how atomic mass was calculated in the 1800's, what with the limited understanding of the atom and all. EverGreg 20:07, 8 October 2007 (UTC)