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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:  2012 PT id = 529

Srivaths–Labarca Periodic Table

This is an improved version of the Zigzag Periodic Table (2012). In this new arrangement the main criteria proposed to settle the placement of the elements hydrogen and helium has been taken into account: electronic configurations, the number of electrons needed to fill the outer-shell, chemical behavior, and triads of atomic number.

This is a new categorial criterion recently proposed by Eric Scerri, according to which hydrogen and helium form part of the triads H(1), F(9), Cl(17) and He(2), Ne(10), Ar(18), respectively. Thus, hydrogen preserves its place between alkali metals and halogen while helium is now in between noble gases and alkaline earth elements.

This periodic table allows visualizing easily the relationships of hydrogen and of helium with the different criteria, avoiding drawing lines to see them in contrast to other similar periodic systems.

Akash Srivaths, Chennai, India
Martín Labarca, CONICET & National University of Quilmes, Argentina

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What is the Periodic Table Showing? Periodicity

© Mark R. Leach Ph.D. 1999 –

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