Periodic Table |
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| What is the Periodic Table Showing? | Periodicity |
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. The database holds information on periodic tables, the discovery of the elements, the elucidation of atomic weights and the discovery of atomic structure (and much, much more).
| Year: 2023 | PT id = 1289, Type = formulation data review |
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 https://doi.org/10.1039/D3DT03738J.
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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