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The INTERNET Database of Periodic Tables

There are thousands of periodic tables in web space, but this is the only comprehensive database of periodic tables & periodic system formulations. If you know of an interesting periodic table that is missing, please contact the database curator: Mark R. Leach Ph.D.

Use the drop menus below to search & select from the more than 1300 Period Tables in the database: 

  Text Search:       

Periodic Tables from the year 2020:

2020   Annotated Periodic Table
2020   What Is A Chemical Element?
2020   FReNeTic
2020   Nuclear Periodic Table
2020   Gierałtowski's Periodic Rotation Table
2020   Nawa Version of Maeno's Nuclear Periodic Table
2020   Vernon's Periodic Table showing the Idealized Solid-State Electron Configurations of the Elements
2020   Correlation of Electron Affinity (F) with Elemental Orbital Radii (rorb)
2020   Periodic Table Challenge
2020   Vernon's Constellation of Electronegativity
2020   Jodogne's Periodic Table of The Elements
2020   artlebedev's 100,000 Permutation Periodic Table of The Elements
2020   Periodic Ziggurat of The Elements
2020   Scerri's Periodic Table of Books About The Periodic Table & The Chemical Elements
2020   Rayner-Canham's The Periodic Table: Past, Present, and Future
2020   Scerri's Periodic Table of Books About The Periodic Table & The Chemical Elements by ERS
2020   Spiral Electron Spin Periodic Table
2020   Molar Magnetic Susceptibilities, Periodic Table of
2020   Lehikoinen's Circular Clock Form
2020   Vernon's Periodic Treehouse
2020   Workshop on Teaching 3d-4s Orbitals Presented by Dr. Eric Scerri
2020   Vernon's (Partially Disordered) 15 Column Periodic Table
2020   Shukarev's Periodic System (redrawn by Vernon)
2020   Allahyari & Oganov: Mendeleev Numbers & Organising Chemical Space
2020   Zig-Zag Line, Periodic Table
2020   16 Dividing Lines Within The Periodic Table
2020   Orbitals of the Outermost Electrons in 2D, Periodic Table of
2020   Split s-, p- & d-Block Periodic Table
2020   Rainbow Periodic Table in ADOMAH Cube
2020   Interview with Chemist, Dr. Eric Scerri
2020   University of UNAM Periodic Table

Year:  2020 PT id = 1097

Annotated Periodic Table

From René Vernon's paper, Vernon, R.E. Organising the metals and nonmetals. Found Chem (2020). (in the supplementary material).

Click image to enlarge.

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Year:  2020 PT id = 1098

What Is A Chemical Element?

A Collection of Essays by Chemists, Philosophers, Historians, and Educators Edited by Eric Scerri and Elena Ghibaudi published by Oxford University Press

The concept of a chemical element is foundational within the field of chemistry, but there is wide disagreement over its definition. Even the International Union for Pure and Applied Chemistry (IUPAC) claims two distinct definitions: a species of atoms versus one which identifies chemical elements with the simple substances bearing their names. The double definition of elements proposed by the International Union for Pure and Applied Chemistry contrasts an abstract meaning and an operational one. Nevertheless, the philosophical aspects of this notion are not fully captured by the IUPAC definitions, despite the fact that they were crucial for the construction of the Periodic Table. Although rich scientific literature on the element and the periodic table exists as well as a recent growth in the philosophy of chemistry, scholars are still searching for a definitive answer to this important question: What is an element?

Eric Scerri and Elena Ghibaudi have teamed up to assemble a group of scholars to provide readers an overview of the current state of the debate on chemical elements from epistemological, historical, and educational perspectives. What Is A Chemical Element? fills a gap for the benefit of the whole chemistry community-experimental researchers, philosophers, chemistry educators, and anyone looking to learn more about the elements of the periodic table.

CHAPTER 1: The many questions raised by the dual concept of 'element' Eric R. Scerri
CHAPTER 2: From simple substance to chemical element Bernadette Bensaude-Vincent
CHAPTER 3: Dmitrii Mendeleev's concept of the chemical element prior to the Periodic Law Nathan M. Brooks
CHAPTER 4: Referring to chemical elements and compounds: Colourless airs in late eighteenth century chemical practice Geoffrey Blumenthal, James Ladyman, and Vanessa Seifert
CHAPTER 5: The Changing Relation Between Atomicity and Elementarity: From Lavoisier to Dalton Marina P. Banchetti-Robino
CHAPTER 6: Origins of the Ambiguity of the Current Definition of Chemical Element Joseph E. Earley
CHAPTER 7: The Existence of Elements, and the Elements of Existence Robin F. Hendry
CHAPTER 8: Kant, Cassirer, and the Idea of Chemical Element Farzad Mahootian
CHAPTER 9: The Operational Definition of the Elements: A Philosophical Reappraisal Joachim Schummer
CHAPTER 10: Substance and Function: The case of Chemical Elements Jean-Pierre Llored
CHAPTER 11: Making elements Klaus Ruthenberg
CHAPTER 12: A formal approach to the conceptual development of chemical element Guillermo Restrepo
CHAPTER 13: Chemical Elements and Chemical Substances: Rethinking Paneth's Distinction Sara N. Hjimans
CHAPTER 14: The dual conception of the chemical element: epistemic aspects and implications for chemical education Elena Ghibaudi, Alberto Regis, and Ezio Roletto
Appendix: Reference list on the philosophy of chemistry Index.

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Year:  2020 PT id = 1104


FReNeTiC is the multi-Award winning 'Frenzied word game of the Elements' where players race against the clock to form as many words as possible using the Element Symbols of The Periodic Table.

In this fast and furious word game players score points equivalent to the atomic numbers of each tile used to create the word, for example Ba Na Na = Banana = 78 points.

The first player to score 1000 points wins!

Everyone plays all the time, quick set up and easy-to-follow rules with FRaNTiC FUN AcTiON! (And no, you don't need to know the Periodic Table or be a GeNiUS to play).

Thanks to Marcus for the tip!

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Year:  2020 PT id = 1110

Nuclear Periodic Table

A nuclear periodic table by Kouichi Hagino & Yoshiteru Maeno from Kyoto University published in Foundations of Chemistry here & here (open access).

"Elements with proton magic-number nuclei are arranged on the right-most column, just like the noble-gas elements in the familiar atomic periodic table.

"The periodic properties of the nuclei, such as their stability and deformation from spherical shape, are illustrated in the table. Interestingly, there is a fortuitous resemblance in the alignments of the elements: a set of the elements with the magic number nuclei 50(Sn), 82(Pb) and Fl(114) also appears as the group 14 elements in the atomic periodic table. Thanks to this coincidence, there are similarities in the alignments beyond 41(Nb) (e.g., Nb-Ta-Db or La-Ac in the same columns) in both the nuclear and atomic periodic tables of the elements.

"Related documents can be found:

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Year:  2020 PT id = 1111

Gierałtowski's Periodic Rotation Table

Sent by Tomasz Gierałtowski from Poland. There is no information, but Tomasz has provided construction diagrams for each period. Click the links to see these:

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Year:  2020 PT id = 1113

Nawa Version of Maeno's Nuclear Periodic Table

Nagayasu Nawa - "A Japanese school teacher and periodic table designer" - has developed two versons of the Hagino-Maeno Nuclear Periodic Table.

Nawa writes:

"I have made two Nuclear PTs based on Hagino-Maeno (2020). I have tried to express the Nuclear PT visually by using symbols such as '〇','◇','☓' or small '〇' or '●' in a binary way so that people with colour blindness could understand it. And the other have been with the ' QUAD electronic data."

Click either of the images below to enlarge:

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Year:  2020 PT id = 1114

Vernon's Periodic Table showing the Idealized Solid-State Electron Configurations of the Elements

René Vernon writes:

"I've attached a periodic table showing the solid-state electron configurations of the elements. Among other things, it provides a first order explanation as to why elements such as Ln (etc.) like the +3 oxidation state.

"The table includes two versions of the f-block, the first starting with La-Ac; the second with Ce-Th. The table with the first f-block version has 24 anomalies [with respect to Madelung's rule]; the table with the second f-block version has 10 anomalies.

"In the case of the Sc-Y-La-Ac form, I wonder if such a solid-state table is more relevant these days than a table based on gas phase configurations, which has about 20 anomalous configurations.

"Partly we use gas phase configurations since, as Eric Scerri mentioned to me elsewhere, configurations were first obtained (~100 years ago?) from spectroscopy, and this field primarily deals with gas phase atoms. That said, are gas phase configurations still so relevant these days – for this purpose – given the importance of solid-state physics?

"I've never been able to find a periodic table of solid-state electron configurations. Perhaps that has something to do with it? Then again, surely I'm not the first person to have drawn one of these?"

Click image below to enlarge:

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Year:  2020 PT id = 1117

Correlation of Electron Affinity (F) with Elemental Orbital Radii (rorb)

From Jour. Fac. Sci., Hokkaido Univ., Ser. IV. vol. 22, no. 2, Aug., 1987, pp. 357-385, The Connection Between the Properties of Elements and Compounds; Mineralogical-Crystallochemical Classification of Elements by Alexander A. Godovikov & Yu Hariya and expanded by René Vernon who writes.

René Vernon writes:

I was delighted to read about two properties that account for nearly everything seen in the periodic table.

Two properties
While researching double periodicity, I happened upon an obscure article, which simply correlates electron affinity with orbital radius, and in so doing reproduces the broad contours of the periodic table. Having never thought much about the value or significance of EA, and its absence of easily discernible trends, I was suitably astonished. The authors left out the Ln and An and stopped at Bi. They were sitting on a gold mine but provided no further analysis.

I added the data up to Lr, updated the EA values, and have redrawn their graph. It is a thing of beauty and wonderment in its simplest sufficient complexity and its return on investment. I've appended 39 observations, covering all 103 elements.


So there it is, just two properties account for nearly everything.

Click images below to enlarge:

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Year:  2020 PT id = 1121

Periodic Table Challenge

IUPAC have developed a Periodic Table Challenge. Answer PT questions at Beginner, Intermediate or Advanced level.

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Year:  2020 PT id = 1122

Vernon's Constellation of Electronegativity

René Vernon has created a "Constellation of Electronegativity" by plotting Electronegativity against Elemental Orbital Radii (rorb)

Observations on the EN plot:

    1. The results are similar to the orbital radii x EA plot, although not quite as clear, including being more crowded
    2. Very good correspondence with natural categories
    3. Largely linear trends seen along groups 1-2, 17 and 15-18 (Ne-Rn)
    4. First row anomaly seen for He (or maybe not since it lines up with the rest of group 2)
    5. For group 13, the whole group is anomalous
    6. For group 14 , the whole group is anomalous no doubt due to the scandide contraction impacting Ge and the double whammy of the lanthanide and 5d contraction impacting Pb
    7. F and O are the most corrosive of the corrosive nonmetals
    8. The rest of the corrosive nonmetals (Cl, Br and I) are nicely aligned with F
    9. The intermediate nonmetals (IM) occupy a trapezium
    10. Iodine almost falls into the IM trapezium
    11. The metalloids occupy a diamond, along with Hg; Po is just inside; At a little outside
    12. Rn is metallic enough to show cationic behaviour and falls into the metalloid diamond
    13. Pd is located among the nonmetals
    14. The proximity of H to Pd is again (coincidentally?) curious given the latter's capacity to adsorb the former
    15. The post-transition metals occupy a narrow strip overlapping the base of the refractory metal parallelogram
    16. Curiously, Zn, Cd, and Hg (a bit stand-off-ish) are collocated with Be, and relatively distant from the PTM and the TM proper
    17. The ostensibly noble metals occupy an oval; curiously, W is found here; Ag is anomalous given its greater reactivity; Cu, as a coinage metal, is a little further away
    18. Au and Pt are nearest to the halogen line
    19. The ferromagnetic metals (Fe-Co-Ni) are colocated
    20. The refractory metals, Nb, Ta, Mo, W and Re are in a parallelogram, along with Cr and V; Tc is included here too
    21. Indium is the central element of the periodic table in terms of mean orbital radius and EN; Tc is next as per the EA chart
    22. The reversal of He compared to the rest of the NG reflects #24
    23. All of the Ln and An fall into an oval of basicity, bar Lr
    24. The reversal of the positions of Fr and Cs is consistent with Cs being the most electronegative metal
    25. A similar, weaker pattern is seen with Ba and Ra. 

Click to enlarge:

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Year:  2020 PT id = 1131

Jodogne's Periodic Table of The Elements

Dr.Ir.Jodogne Jean Claude writes:

"I have the pleasure to send to you my paper on the PT which appears in Chimie Nouvelle 133 of the Soc.Royale de Chimie. However for the moment it is in French. The paper contains and explains the ultimate evolution of my preceding PT but it is the most scientifically based. Pedagogically, I believe it is interesting and easy. As you will see it keeps most of the chemical usual properties of the traditional one."

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Year:  2020 PT id = 1132

artlebedev's 100,000 Permutation Periodic Table of The Elements

Moscow-based design company Art. Lebedev Studio have released a new Periodic Table which can be adapted for any task.

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Year:  2020 PT id = 1147

Periodic Ziggurat of The Elements

By René Vernon, the Periodic Ziggurat of the Elements. Click to enlarge:

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Year:  2020 PT id = 1149

Scerri's Periodic Table of Books About The Periodic Table & The Chemical Elements

From Eric Scerri, a periodic table of books about the periodic table & the chemical elements... many by Eric Scerri himself.

Eric Scerri, UCLA, Department of Chemistry & Biochemistry. See the website and Eric's Twitter Feed.

Click to enlarge:

There is no particular connection between each of the elements and the book associated with it in the table, with the exception of: H, He, N, Ti, V, Nb, Ag, La, Au, Ac, U, Pu & Og.

The following is a list of references for each of the 118 books featured on Periodic Table of Books About The Periodic Table & The Chemical Elements. Books published in languages other than English are shown in color. They include the Catalan, Croatian, French, German, Italian, Norwegian & Spanish languages:

1 H J. Ridgen, Hydrogen, the Essential Element, Harvard University Press, Cambridge, MA, 2002.
2 He W.M. Sears Jr., Helium, The Disappearing Element, Springer, Berlin, 2015.
3 Li K. Lew, The Alkali Metals, Rosen Central, New York, 2009.
4 Be S. Esteban Santos, La Historia del Sistema Periodico, Universidad Nacional de Educación a Distancia, Madrid, 2009. (Spanish)
5 B E.R. Scerri. The Periodic Table, Its Story and Its Significance, 2nd edition, Oxford University Press, New York, 2020.
6 C U. Lagerkvist, The Periodic Table and a Missed Nobel Prize, World Scientific, Singapore, 2012.
7 N W.B. Jensen, Mendeleev on the Periodic Law: Selected Writings, 1869–1905, Dover, Mineola, NY, 2005.
8 O M. Kaji, H. Kragh, G. Pallo, (eds.), Early Responses to the Periodic System, Oxford University, Press, New York, 2015.
9 F E. Mazurs, Graphic Representation of the Periodic System During One Hundred Years, Alabama University Press, Tuscaloosa, AL, 1974.
10 Ne T. Gray, The Elements: A Visual Exploration of Every Known Atom in the Universe, Black Dog & Leventhal, 2009.
11 Na N.C. Norman, Periodicity and the s- and p-Block Elements, Oxford University Press, Oxford, 2007.
12 Mg M. Gordin, A Well-Ordered Thing, Dimitrii Mendeleev and the Shadow of the Periodic Table, 2nd edition, Basic Books, New York, 2019.
13 Al S. Kean, The Disappearing Spoon, Little, Brown & Co., New York, 2010.
14 Si P.A. Cox, The Elements, Oxford University Press, Oxford, 1989.
15 P J. Emsley, The 13th Element: The Sordid Tale of Murder, Fire, and Phosphorus, Wiley, New York, 2002.
16 S P. Parsons, G. Dixon, The Periodic Table: A Field Guide to the Elements, Qurcus, London, 2014.
17 Cl P. Levi, The Periodic Table, Schocken, New York, 1995.
18 Ar B.D. Wiker, The Mystery of the Periodic Table, Bethlehem Books, New York, 2003.
19 K H. Alderesey-Williams, Periodic Tales, Viking Press, 2011.
20 Ca P. Strathern, Mendeleyev's Dream, Hamish-Hamilton, London, 1999.
21 Sc D. Scott, Around the World in 18 Elements, Royal Society of Chemistry, London, 2015.
22 Ti E. W. Collings, Gerhard Welsch, Materials Properties Handbook: Titanium Alloys, ASM International, Geauga County, Ohio, 1994.
23 V D. Rehder, Bioinorganic Vanadium Chemistry, Wiley-Blackwell, Weinheim, 2008.
24 Cr K. Chapman, Superheavy, Bloomsbury Sigma, New York, 2019.
25 Mn E.R. Scerri, E. Ghibaudi (eds.), What is an Element? Oxford University Press, New York, 2020.
26 Fe M. Soon Lee, Elemental Haiku, Ten Speed Press, New York, 2019.
27 Co J. Emsley, Nature's Building Blocks, An A-Z Guide to the Elements, Oxford University Press, Oxford, 2001.
28 Ni T. James, Elemental, Robinson, London, 2018.
29 Cu E.R. Scerri, The Periodic Table, Its Story and Its Significance, Oxford University Press, New York, 2007.
30 Zn H. Rossotti, Diverse Atoms, Oxford University Press, Oxford, 1998.
31 Ga P. Ball, A Very Short Introduction to the Elements, Oxford University Press, 2004.
32 Ge I. Asimov, The Building Blocks of the Universe, Lancer Books, New York, 1966.
33 As J. Browne, Seven Elements that Changed the World, Weidenfeld and Nicholson, London, 2013.
34 Se N. Raos, Bezbroj Lica Periodnog Sustava Elemenata, Technical Museum of Zagreb, Croatia, 2010. (Croatian)
35 Br P. Strathern, The Knowledge, The Periodic Table, Quadrille Publishing, London, 2015.
36 Kr A. Ede, The Chemical Element, Greenwood Press, Westport, CT, 2006.
37 Rb A. Stwertka, The Elements, Oxford University Press, Oxford, 1998.
38 Sr E.R. Scerri, A Tale of Seven Elements, Oxford University Press, New York, 2013.
39 Y H.-J. Quadbeck-Seeger, World of the Elements, Wiley-VCH, Weinheim, 2007.
40 Zr M. Fontani, M. Costa, M.V. Orna (eds.), The Lost Elements, Oxford University Press, New York, 2015.
41 Nb M. Seegers, T. Peeters (eds.), Niobium: Chemical Properties, Applications and Environmental Effects, Nova Science Publishers, New York, 2013.
42 Mo E.R. Scerri, Selected Papers on the Periodic Table, Imperial College Press, Imperial College Press, London and Singapore, 2009.
43 Tc A. Dingle, The Periodic Table, Elements with Style, Kingfisher, Richmond, B.C. Canada, 2007.
44 Ru G. Rudorf, Das periodische System, seine Geschichte und Bedeutung für die chemische Sysytematik, Hamburg-Leipzig, 1904. (German)
45 Rh I. Nechaev, G.W. Jenkins, The Chemical Elements, Tarquin Publications, Publications, Norfolk, UK, 1997.
46 Pd P. Davern, The Periodic Table of Poems, No Starch Press, San Francisco, 2020.
47 Ag C. Fenau, Non-ferrous metals from Ag to Zn, Unicore, Brussells, 2002.
48 Cd J. Van Spronsen, The Periodic System of the Chemical Elements, A History of the First Hundred Years, Elsevier, Amsterdam, 1969.
49 In M. Tweed, Essential Elements, Walker and Company, New York, 2003.
50 Sn M.E. Weeks, Discovery of the Elements, Journal of Chemical Education, Easton PA, 1960.
51 Sb P. Wothers, Antimony Gold Jupiter's Wolf, Oxford University Press, Oxford, 2019.
52 Te W. Zhu, Chemical Elements in Life, World Scientific Press, Singapore, 2020.
53 I O. Sacks, Uncle Tungsten, Vintage Books, New York, 2001.
54 Xe E.R. Scerri, (ed.), 30-Second Elements, Icon Books, London, 2013.
55 Cs M. Jacob (ed.), It's Elemental: The Periodic Table, Celebrating 80th Anniversary, Chemical & Engineering News, American Chemical Society, Washington D.C., 2003.
56 Ba J. Marshall, Discovery of the Elements, Pearson Custom Publishing, New York,1998.
57 La K. Veronense, Rare, Prometheus Books, Amherst, New York, 2015.
58 Ce N. Holt, The Periodic Table of Football, Ebury Publishing, London, 2016.
59 Pr S. Alvarez, C. Mans, 150 Ans de Taules Périodiques a la Universitat de Barcelona, Edicions de la Universitat de Barcelona, Barcelona, 2019. (Catalan)
60 Nd L. Garzon Ruiperez, De Mendeleiev a Los Superelementos, Universidad de Oviedo, Oviedo, 1988. (Spanish)
61 Pm P. Ball, A Guided Tour of the Ingredients, Oxford University Press, Oxford, 2002.
62 Sm S. Esteban Santos, La Historia del Sistema Periodico, Universidad Nacional de Educación a Distancia, Madrid, 2009. (Spanish).
63 Eu A. E. Garrett, The Periodic Law, D. Appleton & Co., New York, 1909.
64 Gd M.S. Sethi, M. Satake, Periodic Tables and Periodic Properties, Discovery Publishing House, Delhi, India, 1992.
65 Tb M. Eesa, The cosmic history of the elements: A brief journey through the creation of the chemical elements and the history of the periodic table, Createspace Independent Publishing Platform, 2012.
66 Dy P. Depovere, La Classification périodique des éléments, De Boeck, Bruxelles, 2002. (French).
67 Ho F. Habashi, The Periodic Table & Mendeleev, Laval University Press, Quebec, 2017.
68 Er W.J. Nuttall, R. Clarke, B. Glowacki, The Future of Helium as a Natural Resource, Routledge, London, 2014.
69 Tm R.D. Osorio Giraldo, M.V. Alzate Cano, La Tabla Periodica, Bogota, Colombia, 2010. (Spanish).
70 Yb P.R. Polo, El Profeta del Orden Quimico, Mendeleiev, Nivola, Spain, 2008. (Spanish).
71 Lu E.R. Scerri, A Very Short Introduction to the Periodic Table, 2nd edition, Oxford University Press, Oxford, 2019.
72 Hf D.H. Rouvray, R.B. King, The Mathematics of the Periodic Table, Nova Scientific Publishers, New York, 2006.
73 Ta P. Thyssen, A. Ceulemans, Shattered Symmetry, Oxford University Press, New York, 2017.
74 W P.W. Atkins, The Periodic Kingdom, Basic Books, New York, NY, 1995.
75 Re D.G. Cooper, The Periodic Table, 3rd edition. Butterworths, London, 1964.
76 Os E. Lassner, W.-D. Schubert, Tungsten: Properties, Chemistry, Technology of the Element, Alloys, and Chemical Compounds, Springer, Berlin, 1999.
77 Ir J.C.A. Boeyens, D.C. Levendis, Number Theory and the Periodicity of Matter, Springer, Berlin, 2008.
78 Pt R. Hefferlin, Periodic Systems and their Relation to the Systematic Analysis of Molecular Data, Edwin Mellen Press, Lewiston, NY, 1989.
79 Au R.J. Puddephatt, The Chemistry of Gold, Elsevier, Amsterdam, 1978.
80 Hg D.H. Rouvray, R.B. King, The Periodic Table Into the 21st Century, Research Studies Press, Baldock, UK, 2004.
81 Tl R.E. Krebs, The History and Use of Our Earth's Chemical Elements, Greenwood Publishing Group, Santa Barbara, CA, 2006.
82 Pb E. Torgsen, Genier, sjarlataner og 50 bøtter med urin - Historien om det periodiske system, Spartacus, 2018. (Norwegian).
83 Bi K. Buchanan, D. Roller, Memorize the Periodic Table, Memory Worldwide Pty Limited, 2013.
84 Po D. Morris, The Last Sorcerers, The Path from Alchemy to the Periodic Table, Joseph Henry Press, New York, 2003.
85 At T. Jackson, The Elements, Shelter Harbor Press, New York, 2012.
86 Rn R.J.P. Williams, J.J.R. Frausto da Silva, The Natural Selection of the Chemical Elements: The Environment and Life's Chemistry, Clarendon Press, Oxford, 1997.
87 Fr G. Rudorf, The Periodic Classification and the Problem of Chemical Evolution, Whittaker & Co., London, New York, 1900.
88 Ra L. Van Gorp, Elements, Compass Point Books, Manakato, MN, 2008.
89 Ac G.T. Seaborg, J.J. Katz, L.R. Morss, Chemistry of the Actinide Elements, Springer, Berlin, 1986.
90 Th G. Münzenberg, Superheavy Elements - Searching for the End of the Periodic Table, Manipal Universal Press, India, 2018.
91 Pa A. Castillejos Salazar, La Tabla Periòdica: Abecedario de la Quimica, Universidad Autonoma de Mexico, D.F. Mexico, 2005. (Spanish).
92 U T. Zoellner, Uranium, Penguin Books, London, 2009.
93 Np J. Barrett, Atomic Structure and Periodicity, Royal Society of Chemistry, London, 2002.
94 Pu J. Bernstein, Plutonium, Joseph Henry, Washington DC, 2007.
95 Am S. Hofmann, Beyond Uranium, Taylor & Francis, London, 2002.
96 Cm H.M. Davis, The Chemical Elements, Ballantine Books, New York, 1961.
97 Bk P.González Duarte, Les Mils Cares de la Taula Periòdica, Universitat Autonoma de Barcelona, Bellaterra Barcelona, 2005 (Catalan).
98 Cf R. Rich, Periodic Correlations, Benjamin, New York, 1965.
99 Es E. Rabinowitsch, E. Thilo, Periodisches System, Geschichte und Theorie, Stuttgart, 1930. (German).
100 Fm P.K. Kuroda, The Origin of the Chemical Elements, and the Oklo Phenomenon, Springer-Verlag, Berlin, 1982.
101 Md G. Villani, Mendeleev,  La Tavola Periodica Degli Elementi, Grandangolo, Milan, 2016. (Italian).
102 No J. Russell, Elementary: The Periodic Table Explained, Michael O'Mara, London, 2020.
103 Lr P. Enghag, Encyclopedia of the Elements, Wiley-VCH, Weinheim, 2004.
104 Rf R.J. Puddephatt, The Periodic Table of the Elements, Oxford University Press, Oxford, 1972.
105 Db L. Ohrström, The Last Alchemist in Paris, Oxford University Press, New York, 2013.
106 Sg N.N. Greenwood, E. Earnshaw, Chemistry of the Elements, 2nd edition, Elsevier, Amsterdam, 1997.
107 Bh R. Luft, Dictionnaire des Corps Simples de la Chimie, Association Cultures et Techniques, Nantes, 1997. (French)
108 Hs Science Foundation Course Team, The Periodic Table and Chemical Bonding, The Open University, Milton Keynes, 1971.
109 Mt W.W. Schulz, J. Navratil, Transplutonium Elements, American Chemical Society, Washington D.C., 1981.
110 Ds I. Nechaev, Chemical Elements, Lindsay Drummond, 1946.
111 Rg F. Hund, Linienspektren und Periodisches System Der Elemente, Springer, Berlin, 1927.
112 Cn F.P. Venable, The Development of the Periodic Law, Chemical Publishing Co., Easton, PA, 1896.
113 Nh O. Baca Mendoza, Leyes Geneticas de los Elementos Quimicos. Nuevo Sistema Periodico, Universidad Nacional de Cuzco, Cuzco, Peru, 1953 (Spanish).
114 Fl B. Yorifuji, Wonderful Life with the Elements, No Starch Press, San Francisco, 2012.
115 Mc D.I. Mendeléeff, The Principles of Chemistry, American Home Library, New York, 1902.
116 Lv A. Lima-de-Faria, Periodic Tables Unifying Living Organisms at the Molecular Level: The Predictive Power of the Law of Periodicity, World Scientific Press, Singapore, 2018.
117 Ts H.B. Gray, J.D. Simon, W.C. Trogler, Braving the Elements, University Science Books, Sausalito, CA, 1995.
118 Og E.R. Scerri, G. Restrepo, Mendeleev to Oganesson, Oxford University Press, New York, 2018.
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Year:  2020 PT id = 1152

Rayner-Canham's The Periodic Table: Past, Present, and Future

A book by Geoff Rayner-Canham, The Periodic Table: Past, Present, and Future. | August 2020


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Year:  2020 PT id = 1153

Scerri's Periodic Table of Books About The Periodic Table & The Chemical Elements by ERS

From Eric Scerri, a periodic table of books about the periodic table & the chemical elements... by Eric Scerri, including translations.

Eric Scerri, UCLA, Department of Chemistry & Biochemistry. See the website and Eric's Twitter Feed.

Click to enlarge:

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Year:  2020 PT id = 1154

Spiral Electron Spin Periodic Table

The Spiral Electron Spin Periodic Table, By Justine Colburn, who also developed the Genesis formulation.

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Year:  2020 PT id = 1157

Molar Magnetic Susceptibilities, Periodic Table of

Periodic Table of Molar Magnetic Susceptibilities by René Vernon, who writes:

I had read that the lanthanides were characterised by their magnetic properties, but never fully appreciated what this means. To this end, here is a table of Molar Magnetic Susceptibility (MMS) values (χ) for the elements, where MMS is a measure of how much a material will become magnetised in an applied magnetic field.

Formally, MMS is the ratio of magnetisation M (magnetic moment per unit volume) to the applied magnetising field of intensity H, allowing a simple classification into two categories of most materials responses to an applied magnetic field:

Alignment with the magnetic field, χ > 0, gives rise to paramagnetism
Alignment against the magnetic field, &chi; < 0, gives rise to diamagnetism

Six observations:

1. The average value for each block is:

2. Lanthanides having unpaired 4f metals (Ce to Tm) have magnetic susceptibilities two to four orders of magnitude larger than those of "normal" metals.

3. Mn (511), Pd (540), O (3415) [this is actually the triplet diradical molecule O2] & Bi (-280) stand out. [A magnetic cross would be good for repelling a bismuth vampire.]

4. MMS reduces going down all groups of the d-block. The average reduction going from 4d to 5d is 50%.

5. In group 3 there is a reduction of 48% on going from Y to La. If Lu is instead placed under Y the reduction is 2%.

6. There are at least six, rather than three, ferromagnetic metals.

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Year:  2020 PT id = 1158

Lehikoinen's Circular Clock Form

Otto Lehikoinen writes:

"A circular form separating 1s orbital to the center, set it on a wall clock as there are 48 elements of main periods, thus can be used as markers for half hours. Group 4 is centered on noon and group 7 starts the afternoon, to get anions and cations with the same but opposite charge to be beside each other. Thus the noble gases are centered on midnight which is easily remembered by neon (and other noble gas) lights. The minute hand hits the 40 d-block elements giving an accuracy of 1.5 minutes and seconds could be read from lanthanides and actinides."

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Year:  2020 PT id = 1161

Vernon's Periodic Treehouse

René Vernon's Periodic Treehouse of the Elements, fearuring the World's longest dividing line between metals and nonmetals.

René writes:

I can't remember what started me off on this one. It may have been Mendeleev's line, as shown on the cover of Bent's 2006 book, New ideas in chemistry from fresh energy for the periodic law.

There are a few things that look somewhat arbitrary, so I may revisit these:

Click to enlarge:

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Year:  2020 PT id = 1162

Workshop on Teaching 3d-4s Orbitals Presented by Dr. Eric Scerri

Dr. Eric Scerri, UCLA Department of Chemistry & Biochemistry, discusses many of the issues concerning the periodic table: the aufbau principle, Madelung's rule, the electronic and anomalous electronic structures of the transition elements, the Sc2+ ion, the Janet Left Step, Group 3: Sc, Y, Lu, Lr vs. Sc, Y, La, Ac, atomic spectroscopy, etc.

Many of the topics that concern those of us interested in the periodic table are discussed.

Thanks to Eric Scerri – who appears – for the tip! 
See the website and Eric's Twitter Feed.

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Year:  2020 PT id = 1165

Vernon's (Partially Disordered) 15 Column Periodic Table

A formulation by René Vernon, who writes:

"Here is a 15-column table which is a hybrid of a Mendeleev 8-column table and an 18-column standard table. The key relocations are the p-block nonmetals to the far left; and the coinage and post-transition metals under their s and early d-block counterparts.

"Taking a leaf out of Mendeleev's playbook, I ignored atomic number order when this seemed appropriate. It's refreshing to see the traditional horizontal gaps between blocks disappear. (DIM did not like these.)

"Since Dias (2004, see references below) reckoned a periodic table is a partially ordered set forming a two-dimensional array, I believe I now have a partially ordered table that is partially disordered twice over.

"The table has some curious relationships. Equally, some relationships seen in the standard form are absent. The Group 2, 3, and aluminium dilemmas disappear. This confirms my impression that such dilemmas have no intrinsic meaning. Rather, their appearance or non-appearance is context dependent."

Notes & references below.

Groups 1 to 4 have either a C or F suffix where C (nonmetal) is after the importance of carbon to our existence; and F (metal) is for the importance of iron to civilisation.

Groups 1C and 1F present the greatest contrast in nonmetallic and metallic behaviour.

Coactive Nonmetals: They are capable of forming septenary heterogeneous compounds such as C20H26N4O10PSSe.

Group 2C: Helium is shaded as a noble gas. "Heliox" is a breathing gas mixture of helium and oxygen used in saturation diving, and as a medical treatment for patients with difficulty breathing.

Group 3C: Boron over nitrogen looks odd. Yet one boron atom and one nitrogen atom have the same number of electrons between them as two adjacent carbon atoms. The combination of nitrogen and boron has some unusual features that are hard to match in any other pair of elements (Niedenzu & Dawson 1965).

Boron and phosphorus form a range of ring and cage compounds having novel structural and electronic properties (Paine et al. 2005).

Metalloids. I treat them here as nonmetals given their chemistry is predominately that of chemically weak nonmetals.

Metals: The labels electropositive; transition; and electronegative are adapted from Kornilov (2008).

Group 1F: Monovalent thallium salts resemble those of silver and the alkali metals.

An alloy of cesium (73.71%), potassium (22.14%) and sodium (4.14%) has a melting point of –78.2°C (–108.76°F) (Oshe 1985).

Silver, copper, and gold, as well as being the coinage metals, are borderline post-transition metals.

Group 2F: Beryllium and magnesium are not in fact alkaline earths. Beryllium is amphoteric rather than alkaline; magnesium was isolated in impure form from its oxides, unlike the true alkaline earths. The old ambiguity over whether beryllium and magnesium should go over calcium or zinc has gone.

Nobelium is here since +2 is its preferred oxidation state, unlike other actinoids.

Group 3F: Aluminium is here in light of its similarity to scandium (Habishi 2010).

InGaAsP is a semiconducting alloy of gallium arsenide and indium phosphide, used in lasers and photonics.

There is no Group 3 "issue" since lanthanum, actinium, lutetium and lawrencium are in the same family.

Gold and aluminium form an interesting set of intermetallic compounds known as Au5Al2 (white plague) and AuAl2 (purple plague). Blue gold is an alloy of gold and either gallium or indium.

Lanthanoids: The oxidation state analogies with the transition metals stop after praseodymium. That is why the rest of lanthanoids are footnoted in dash-dot boxes.

Actinoids: The resemblance to their transition metal analogues falters after uranium, and peters out after plutonium.

Group 4F: It's funny to see titanium—the lightweight super-metal—in the same group as lead, the traditional "heavy" metal.

This is the first group impacted by the lanthanoid contraction (cerium through lutetium) which results in the atomic radius of hafnium being almost the same as that of zirconium. Hence "the twins".

The chemistry of titanium is significantly different from that of zirconium and hafnium (Fernelius 1982).

Lead zirconate titanate Pb[ZrxTi1–x]O3 (0 ≤ x ≤ 1) is one of the most commonly used piezo ceramics.

Group 5: Bismuth vanadate BiVO4 is a bright yellow solid widely used as a visible light photo-catalyst and dye.

Steel Friends: The name is reference to their use in steel alloys. They have isoelectronic soluble oxidizing tetroxoanions, plus a stable +3 oxidation state. (Rayner-Canham 2020).

Ferromagnetic Metals: The horizontal similarities among this triad of elements (as is the case among the PGM hexad) are greater than anywhere in the periodic table except among the lanthanides (Lee 1996). The +2 aqueous ion is a major component of their simple chemistry (Rayner-Canham 2020).

Group 8: "Rubiferous metals" (classical Latin rubēre to be red; -fer producing) is from the reddish-brown colour of rust; the most prevalent ruthenium precursor being ruthenium trichloride, a red solid that is poorly defined chemically but versatile synthetically; and the red osmates [OsO4(OH)4]?2 formed upon reaction by osmium tetroxide with a base.

Group 9: "Weather metals" comes from the use of cobalt chloride as a humidity indicator in weather instruments; rhodium plating used to "protect other more vulnerable metals against weather exposure as well as against concentrated acids or acids fumes" (Küpfer 1954); and the "rainbow" etymology of iridium.

Group 10: "Catalytic metals" is after a passage in Greenwood and Earnshaw, "They are... readily obtained in finely divided forms which are catalytically very active." (2002). Of course, many transition metals have catalytic properties. That said, if you asked me about transition metal catalysts, palladium and platinum would be the first to come to mind. Group 10 appear to be particularly catalytic.


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Year:  2020 PT id = 1168

Shukarev's Periodic System (redrawn by Vernon)

Shukarev SA 1975, "On the image of the periodic system with the use of fifth move of late a-elements", Collection of Scientific and Methodological Articles on Chemistry. M.: Higher School, no 4, pp 3-12 (in Russian). Redrawn and commented upon by René Vernon:

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Year:  2020 PT id = 1169

Allahyari & Oganov: Mendeleev Numbers & Organising Chemical Space

This formulation may not look like a periodic table, but look again.

Zahed Allahyari & Artem R. Oganov, Nonempirical Definition of the Mendeleev Numbers: Organizing the Chemical Space, J. Phys. Chem. C 2020, 124, 43, 23867–23878, A preprint version of the paper is available on the arxiv preprint server.


Organizing a chemical space so that elements with similar properties would take neighboring places in a sequence can help to predict new materials. In this paper, we propose a universal method of generating such a one-dimensional sequence of elements, i.e. at arbitrary pressure, which could be used to create a well-structured chemical space of materials and facilitate the prediction of new materials.

This work clarifies the physical meaning of Mendeleev numbers, which was earlier tabulated by Pettifor. We compare our proposed sequence of elements with alternative sequences formed by different Mendeleev numbers using the data for hardness, magnetization, enthalpy of formation, and atomization energy. For an unbiased evaluation of the MNs, we compare clustering rates obtained with each system of MNs.

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Year:  2020 PT id = 1170

Zig-Zag Line, Periodic Table

Periodic Table showing the (regular) zig-zag line by René Vernon who writes:

"It is curious that the full extent of the line has never been properly mapped (to my knowledge).

"Elements on the downside of the line generally display increasing metallic behaviour; elements on the topside generally display increasing nonmetallic behaviour.

"When you see the line you will usually see only about a quarter of it. The line actually runs all the way across the periodic table, as shown, for a total of 44 element box sides.

"Interpretations vary as to where the line runs. None of these is better than any other of them, provided the interpretation is explained to you. The thick black line (at least in the p-block) is the most common version. The metalloids tend to lie to either side of it.

"Polonium and astatine are shown here as post-transition metals although either or both of them are sometimes shown as metalloids (or, in the case of astatine, as a halogen). Polonium conducts electricity like a metal and forms a cation in aqueous solution. In 2013, astatine was predicted to be a centred cubic-metal Condensed Astatine: Monatomic and Metallic This prediction has been cited 35 times, with no dissenters. Astatine also forms a cation in aqueous solution. Oganesson is shown as having (as yet) unknown properties.

"The dashed lines show some alternative paths for the zigzag line.

"The lower one treats the metalloids as nonmetals since metalloid chemistry is predominately nonmetallic. The lower line and the upper line are sometimes shown together used when the metalloids are treated as neither metals nor nonmetals."

And in Janet Left-Step form:

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Year:  2020 PT id = 1171

16 Dividing Lines Within The Periodic Table

René Vernon points out that there are 16 dividing lines within the periodic table.

A-Z Dividing Lines:

48-crash line: Named after the dramatic reduction in physical metallic character after group 11, Cd being Z = 48. Group 12 show few transition metal attributes and behave predominantly like post-transition metals.

Big bang line: H makes up about 73% of the visible universe.

Corrosive line: O, F, Cl = most corrosive nonmetals.

d-Block fault line: Group 3 show little d-block behaviour; group 4 is the first in which characteristic d-block behaviour occurs.

Deming line: Demarcates the metalloids from the pre-halogen nonmetals. The "reactive" nonmetals to the right of the metalloids each have a sub-metallic appearance (C, O, Se, I).

Edge of the world line: No guesses for this one.

Klemm line: Klemm, in 1929, was the first to note the double periodicity of the lanthanides (Ce to Lu). Lockyer line: After the discoverer of He, the first element not found on Earth.

Ørsted line: After the magnetic effects believed to be responsible for Mn having a crystalline structure analogous to white P; Tc: First radioactive metal; Re: Last of the refractory metals; "most radioactive" of the naturally occurring elements with stable isotopes. Fe: First of the ferromagnetic metals; Ru: First noble metal; Os: Densest of naturally occurring metals. The number of unpaired d electrons peaks in group 7 and reduces thereafter.

Platypus line: Tl shows similarities to Rb, Ag, Hg, Pb.

Poor metal line: Most metals (80%) have a packing factor (PF)3 68%. Ga: Has a crystalline structure analogous to that of iodine. BCN 1+6.* PF 39.1%. Melts in your hand. In: Partly distorted structure due to incompletely ionised atoms. BCN 4+8. PE 68.6%. Oxides in preferred +3 state are weakly amphoteric; forms anionic indates in strongly basic solutions. Tendency to form covalent compounds is one of the more important properties influencing its electro-chemical behaviour. Sn: Irregularly coordinated structure associated with incompletely ionised atoms. BCN 4+2. PF 53.5%. Oxides in preferred +2 state are amphoteric; forms stannites in strongly basic solutions. Grey Sn is electronically a zero band gap semimetal, although it behaves like a semiconductor. Diamond structure. BCN 4. PF 34.0%. Pb: Close-packed, but abnormally large inter-atomic distance due to partial ionisation of Pb atoms. BCN 12. PF 74%. Oxide in preferred +2 state is amphoteric; forms anionic plumbates in strongly basic solutions. Bi: Electronic structure of a semimetal. Open-packed structure (3+3) with bonding intermediate between metallic and covalent. PF 44.6%. Trioxide is predominantly basic but will act as a weak acid in warm, very concentrated KOH. Can be fused with KOH in air, resulting in a brown mass of potassium bismuthate.

Seaborg line: No f electrons in gas phase La, Ac and Th atoms.

Triple line: N = gas; S = solid; Br = liquid.

Zigzag lobby: H needs no intro. Li: Many salts have a high degree of covalency. Small size frequently confers special properties on its compounds and for this reason is sometimes termed 'anomalous'. E.g. miscible with Na only above 380° immiscible with molten K, Rb, Cs, whereas all other pairs of AM are miscible with each other in all proportions. Be: Has a covalent component to its otherwise predominately metallic structure = low ductility. Lowest known Poisson's ratio of elemental metals. Amphoteric; predominately covalent chemistry atypical of group 2. Some aspects of its chemical properties are more like those of a metalloid.

Zigzag line: Eponymous metal-nonmetal dividing line.

Zintl line: Hypothetical boundary highlighting tendency for group 13 metals to form phases with a various stoichiometries, in contrast to group 14+ that tend to form salts with polymeric anions.

* BCN = bulk coordination number

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Year:  2020 PT id = 1173

Orbitals of the Outermost Electrons in 2D, Periodic Table of

By Meszi of, a Periodic Table of Orbitals of the Outermost Electrons in 2D, from reddit.

Click image to enlarge:

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Year:  2020 PT id = 1174

Split s-, p- & d-Block Periodic Table

René Vernon presents a periodic table formulation with split s-, p- & d-blocks.

The details: Group 3 as B-Al-Ga-In-Tl

Al over Sc has some history, which seems to have been forgotten.

Here are some other tables with B-Al-Sc-Y-La:

What was it that these luminaries knew about B-Al-Sc-Y-La-Ac that is deemed to be no longer relevant, and why is that the case?

Deming (1947, Fundamental Chemistry, 2nd ed. p. 617) located Al with the pre-transition metals in groups 1?2. Cox (2004, Inorganic Chemistry, 2nd ed. p. 185) refers to the pre-transition metals as those in groups 1 and 2, and Al. Here's that 2019 periodic table (by me), recording oxidation number trends, further suggesting B and Al are better placed over Sc.

In this vein, Rayner-Canham (2020, The periodic table: Past, present, and future, pp. 178–181) writes:

"It was Rang in 1893 who seems to have been the first, on the basis of chemical similarity, to place boron and aluminum in Group 3.

"Such an assignment seems to have been forgotten until more recent times. Greenwood and Earnshaw have discussed the way in which aluminum can be considered as belonging to Group 3 as much as to Group 13 particularly in its physical properties. Habashi has suggested that there are so many similarities between aluminum and scandium that aluminum's place in the Periodic Table should actually be shifted to Group 3.

"In terms of the electron configuration of the tripositive ions, one would indeed expect that Al3+ (electron configuration, [Ne]) would resemble Sc3+ (electron configuration, [Ar]) more than Ga3+ (electron configuration, [Ar]3d10). Also of note, the standard reduction potential for aluminum fits better with those of the Group 3 elements than the Group 13 elements (Table 9.2) – as does its melting point.

"In terms of their comparative solution behavior, aluminum resembles both scandium(III) and gallium(III). For each ion, the free hydrated cation exists only in acidic solution. On addition of hydroxide ion to the respective cation, the hydroxides are produced as gelatinous precipitates. Each of the hydroxides redissolve in excess base to give an anionic hydroxo-complex, [M(OH)4]... There does seem to be a triangular relationship between these three elements. However, aluminum does more closely resemble scandium rather than gallium in its chemistry. If hydrogen sulfide is bubbled through a solution of the respective cation, scandium ion gives a precipitate of scandium hydroxide, and aluminum ion gives a corresponding precipitate of aluminum hydroxide. By contrast, gallium ion gives a precipitate of gallium(III) sulfide. Also, scandium and aluminum both form carbides, while gallium does not."

To answer my own question as to why group 3 as B-Al-Sc-Y-La-Ac has been forgotten.

I suspect what happened is that it was historically known that group 3 was better represented as B-Al-Sc-Y-La-[Ac]. Then, with the advent and rise of modern electronic structure theory, B-Al- got moved to the p-block because, after all, they were p-block elements, never mind the damned chemistry. And La stayed in the d-block since it was the first element to show 5d electron, and 4f did not show until Ce. And Lu stayed where it was since even thought it was learnt that the f shell become full at Yb, rather than Lu, nothing changed about the chemistry of Lu. Nowadays, this has all been forgotten.

The modern periodic table is a chemistry-physics hybrid.

Lu in group 3 demands He over Be. La in group 3 demands B-Al over Sc. Neither option gets up. The more important consideration is to teach the history and have students and chemists appreciate both perspectives.

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Year:  2020 PT id = 1175

Rainbow Periodic Table in ADOMAH Cube

From the prolific Nagayasu Nawa, a version of his Rainbow Periodic Table inside Valery Tsimmerman's glass cube:

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Year:  2020 PT id = 1176

Interview with Chemist, Dr. Eric Scerri

From Academic Influence. We met with Dr. Eric Scerri to discuss the nature of science, the philosophy of chemistry, and much more. Enjoy!

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Year:  2020 PT id = 1295

University of UNAM Periodic Table

Mexico City, University of UNAM Chemistry Department

Thanks to Marcus for the tip!

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