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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: 

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Year:  2010 PT id = 277

Periodic Arch of The Elements

Cynthia K. Whitney of Galilean Electrodynamics writes: "In his paper Explaining the periodic table, and the role of chemical triad, Eric Scerri mentioned the existence of at least four different candidate places for Hydrogen: Group 1 (alkali metals - Lithium, etc.), Group 17 (halogens - Fluorine, etc.), Group 14 (Carbon, etc.), or off the Periodic Table entirely, because it is so odd! The four-fold multiplicity (and maybe more) of candidate places for Hydrogen triggered in me the following thought: the excessive multiplicity of candidate places may have to do with the rectangular nature of the Periodic Tables under consideration there." Read more in this pdf file.

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What is the Periodic Table Showing? Periodicity

© Mark R. Leach Ph.D. 1999 –

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