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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:       

Year:  2006 PT id = 56

Reaction Chemists' Periodic Table

OK, so which Is The Best formulation of The Periodic Table?

Personally as a reaction chemist, my preferred periodic table is the 'long' form shown below, with hydrogen above and between boron and carbon, although clearly other scientists have other ideas.

All periodic tables show the increase in mass and atomic number, Z, but only the long form unambiguously shows the general top-right-to-bottom-left trends in electronegativity, atomic radius, metallic properties and first ionisation energy.

Electronegativity is absolutely crucial to the understanding of structure, bonding, material type (van Arkel-Ketelaar triangle and Laing tetrahedron) and chemical reactivity, and it underpins much of the chemogenesis analysis.

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What is the Periodic Table Showing? Periodicity

© Mark R. Leach Ph.D. 1999 –

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