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: 1916 | PT id = 541, Type = formulation |
Dushman's Periodic System of The Elements (after Mendelejeff)
Saul Dushman's article, "The Periodic Law", published in the General Electric Review (Vol. 18, pp. 614–621) in July 1915, provides a comprehensive overview of the status of the periodic law in the early 20th century.
Key Aspects of the Article:
- Historical Context: It reviews the development of the periodic classification, honouring the foundational work of Dmitri Mendeleev.
- Modernizing the Law: Writing just over a decade after the discovery of radioactivity and the electron, Dushman bridges the gap between Mendeleev’s empirical atomic weight law and emerging quantum-physical understandings of atomic structure.
- Radioactivity and Isotopes: The article discusses the impact of radioactivity research (including Soddy's work on isotopes) on the periodic table, explaining how many "new" radioactive elements were found to belong to the same place in the table.
- Atomic Number: It touches upon the significance of atomic numbers as a more fundamental ordering principle than atomic weight, a crucial transition in understanding atomic structure.
- Significance: It highlights the periodic law as the "most fundamental natural system of classification ever devised", marking a transition from chemical phenomenology to physical explanation.
The article is representative of the era's shift toward interpreting chemistry through atomic structure and the revolutionary discoveries of Moseley and Rutherford.

Thanks to Eric Scerri for the tip!
See the website EricScerri.com and Eric's Twitter Feed.
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| What is the Periodic Table Showing? | Periodicity |
© Mark R. Leach Ph.D. 1999 –
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