Critical Review: Analysis of
"WebElements TM" periodic table 
Kritische Betrachtung, Analyse des Periodensystem von  "WebElements"  

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english language    

At first glance, Dr. Mark Winter's periodic table looks just like other periodic tables which are familiar to chemists.
  German language

Auf den ersten Blick scheint das Periodensystem von Dr. Mark Winter wie jedes dem Chemikern geläufige Periodensystem auszusehen. 

SCREEN-PRINT 09/21/2002

Link:  http://www.webelements.com    Dr. Mark Winter 
 

CHEMISTRY AT SHEFFIELD
 

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However, not to me. In my opinion, there is a serious mistake.

The elements 71 and 103 are incorrectly placed under 21 and 39, respectively.

Reason: 

1. IUPAC  
Dr. Winter conforms to the suggested IUPAC-convention of using wildcard characters for the Lanthanide and Actinide series. Reading direction is from left-to-right and not from right-to-left.
( sees counting direction 1 2 3 4 5)

Für mich  jedoch nicht. Meines Erachtens liegt hier ein gravierender 39-71 Fehler vor. 

Die Elemente 71 und 103 werden fälschlich unter 21 und 39 gestellt.

Begründung:

1. IUPAC
Dr. Winter weicht hier von der empfohlenen IUPAC-Schreibweise der Platzhalter für die Lanthaniden- und Actinidengruppe ab. Leseweise ist von links nach rechts und nicht von rechts nach links.
(siehe Zählrichtung  1 2 3 4 5 )

part of the IUPAC periodic table
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2. Higgledy-piggledy 
Calculation 39 [Sc-Y-?]  and 71 [ ? -Lu-Lr]

3. Orbital-calculation 
Quant. mechanical calculations are negated. 

4. Symmetry of the period-system 
The Truss - calculation is negated. 
1x4-Cascade [4,12,20,38] against  2x2-Cascads. Outblocking of elements 

5. Chemical properties 
The chemical relationship between elements, 21 [Sc], 39 [Y], and, 57 [La], 89 [Ac], is negated.

2. Darunter und darüber liegende Elemente  
Berechnung 39  [Sc-Y-?]  und 71  [ ?-Lu-Lr]

3. Orbitalberechnung
Quantenmechanische Berechnungen werden negiert. 

4. Symmetrie des Periodensystems  
Die Truss-Berechnung wird negiert. 
4er-Cascade[4,12,20,38] contra 2er-Cascaden. Outblocking of elements 

5. Chemische Eigenschaften
Die chemische Beziehung zwischen Element (21 [Sc], 39 [Y]) und (57 [La], 89 [Ac]) wird aufgehoben.

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Pictorial reply, to clarify about the differences.Bildliche Gegendarstellung, um die Unterschiede zu verdeutlichen.

 
Pictorial reply

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Epilogue: 

It should be pointed out that Dr. Mark Winter's homepage is one of the best on the web, and is being used to serve as an example to call attention to this existing problem.

I will welcome opposing mathematical views if you consider the form of Dr. Winter's periodic table to be correct. 

Nachwort: 

Es sei darauf hingewiesen, das die Homepage von Dr. Mark Winter eine der besten im Web ist und nur exemplarisch herausgegriffen wurde, um auf dieses bestehende Problem aufmerksam zu machen.

Ich erwarte jedoch eine fundierte, mathematische  Gegendarstellung falls diese Form des Periodensystems von Dr. Winter widererwarten richtig sein sollte.
 

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Counter-argument of the periodic table layout

 "The positions of the elements La, Ac, Lu, and Lr in the WebElements periodic table is justified in the article by William B. Jensen, The Positions of Lanthanum (Actinium) and Lutetium (Lawrencium) in the Periodic Table, Journal of Chemical Education, 1982, 59, p. 634-636."  

http://www.webelements.com/webelements/support/text/help/layout.html

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Holleman-Wiberg's Inorganic Chemistry
edited by Nils Wiberg
Academic Press: New York, NY, 2001. xxxix + 1884 pp.
ISBN 0-12-352651-5.

Prof. William B. Jensen          http://www.che.uc.edu/fac_staff/jensen_william.html
Department of Chemistry, University of Cincinnati, OH 45221-0172
Journal of Chemical Education

The first edition of this textbook was published in 1898 by the Dutch chemist, Arnold Frederick Holleman (1859­1953). In 1900 it was translated into German and in this form rapidly became one of the most popular texts in the field. As of 1995, it has passed through 34 German editions and more than 100 printings. In 1943 editorship of the text was taken over by the German chemist, Egon Wiberg, and since then it has become known simply as Holleman-Wiberg among German-speaking chemists. Though the book's cover claims that the current edition, under the editorship of Nils Wiberg, is the first to be translated into English, this is, in fact, not true. The original Dutch edition was actually translated into English in 1902 by Hermon Cooper of Syracuse University and went through at least six editions by 1921. By then it had become too advanced for use in most American universities, few of which taught inorganic courses beyond the freshman level prior to the Second World War.

The current translation weighs in at 1884 pages and is printed on a light-weight grade of paper that has some problems with print bleed through. The size is a consequence of the book's attempt to be thorough in its coverage. Whereas most American inorganic texts deal primarily with either concepts and models or with systematic descriptive chemistry (and, in the latter case, are often biased toward coverage of the transition metals), this text attempts to include both approaches. This is done by dividing the book into four sections: Part A, (8 chapters, 276 pages) deals with fundamental concepts; Part B (10 chapters, 848 pages) deals with the chemistry of the main-group elements; Part C (14 chapters, 514 pages) deals with the chemistry of the outer-transition elements, and Part D (4 chapters, 104 pages) deals with the chemistry of the lanthanoids and actinoids. These are followed by 27 pages of appendices and by both a name and subject index.

The coverage of concepts in Part A is basically at the level of an advanced freshman text. Given the average student's claims of total amnesia when it comes to the contents of earlier courses, this is probably not a bad idea and is also in keeping with the editor's stated claim that the book is intended for use by both beginning and advanced students. Compared with the dog-and-pony show that now passes for the average freshman textbook­with its multicolored pages, photos, sidebars, and supplementary CD's­it is refreshing to see this material presented using straight-forward, unpretentious, black and white, line drawings and print.

The coverage of descriptive chemistry in Parts B, C, and D includes not only the latest research results but also basic information on naturally occurring mineral sources of the elements and on important industrial processes, such as iron smelting, the chemistry of glass, ceramics and cement­topics that have all but disappeared from most American textbooks.

One unique feature of the book is its four-part coverage of the periodic law­an introductory chapter for Part A, and general overview chapters on each of the three major electronic blocks distributed among Parts B, C, and D. Regrettably, the book's treatment of this topic is one of the few with which I would take issue.

Part C incorrectly classifies La and Ac as d-block or outer-transition metals even though extensive evidence was presented over 20 years ago (J. Chem. Educ. 1982, 59, 634­636) showing that they are in fact f-block elements with irregular configurations and that Lu and Lr actually occupy the positions below Sc and Y in the d-block.

Even more serious is the insistence that Zn, Cd, and Hg are outer-transition metals, though in fact there is nothing in either their electronic configurations or their known chemistry that could possibly justify such a classification. A related, albeit minor, criticism is the book's decision to use the terms lanthanide and actinide rather than the more linguistically correct terms lanthanoid and actinoid.

http://jchemed.chem.wisc.edu/Journal/Issues/2002/Aug/abs944.html

Citation: Jensen, William B. J. Chem. Educ. 2002 79 944.
 

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Review of WebElements 
2002-08-30
By Research Librarian Søren Møller, Roskilde Univertity Library. DEF-subject editor for chemistry.   http://www.deff.dk/fagredaktion/anmeldelser/webelements.htm

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The Periodic Table of the Elements is a basic tool for the description and prediction of the physical and chemical properties of the elements.

The Internet contains numerous examples on periodic tables which - at varying degrees - take advantage of the special possibilities which this media presents. One project, WebElements, stands out as the most thorough. WebElements is authored by Mark Winter, Department of Chemistry, University of Sheffield, England and was (probably) the first of its kind. As in most Internet editions of the periodic table each element is a hyperlink that links to information on physical/chemical properties, electron configuration, isotopes, geology, use, and history. In addition photographs of the pure elements are shown along with information on simple compounds (halogenides, hydrides, oxides a.o.). The big advantage of WebElements compared to other periodic tables is the extent of information and the navigation options. It is easy to jump from element to element by a "go adjacent" box with the nearest neighbours and by an alphabetic "pull-down" menu. References to the literature are available wherever it's relevant. It is beyond the scope of this review to test the quality of data presented, but should someone stumble over an error they just fill in a form available for that purpose. If in doubt of the pronunciation of an element name then click on an icon and you will hear the name pronounced by a female and a male voice - or you may prefer to listen to Tom Lehrer's "Elements song".

During my search for the best periodic tables on the Internet for the "DEF link collection" I came across a few interesting versions which, however, were not selected. Here are some of the more bizarre: An "Extended Periodic Table" including elements up to no. 218, The Periodic Table of Comic Books with references to the comic literature, and The Periodic Table of Rejected Elements. You should also check out the periodic table written with Chinese characters. A comprehensive list of periodic tables on the Internet can be viewed at Links for Chemists.

http://www.ilpi.com/genchem/periodicquiz.html  The Periodic Table Challenge

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APSIDIUM   Created:2002-09-23    PDF
webelements.pdf
Top HomeLast Updated:2007-05-24 

 

Benachrichtigung  von Dr. Mark Winter am 24.09.2002
Thanks  to Scott A. Brown