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 hold information on periodic tables, the discovery of the elements and elucidation of atomic weights (and 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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