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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:  2023 PT id = 1289

Chemdex: Valence & Oxidation Number Trends

From Mark Winter's review paper Chemdex: quantification and distributions of valence numbers, oxidation numbers, coordination numbers, electron numbers, and covalent bond classes for the elements Dalton Trans., 2024,53, 493-511

The images below show the Valence number (VN) and oxidation number (ON) proportions as percentages for the elements; and Periodic tables displaying valence number proportions (%). (There are few data for Pm and no data for Fr and elements beyond Es.)

The position of H and the group numbers are addressed in the paper.

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What is the Periodic Table Showing? Periodicity

© Mark R. Leach Ph.D. 1999 –

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