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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:  1920 PT id = 1070

Black & Conant's Periodic Classification Of The Elements

From N.H. Black NH & J.B. Conant's Practical Chemistry: Fundamental Facts and Applications to Modern Life, MacMillan, New York (1920)

Eric Scerri, who provided this formulation writes (personal communication):

"Notice conspicuous absence of H. And, Conant was the person who gave Kuhn his first start in the history of science at Harvard."

René Vernon tells us that Conant and his coauthor write:

"The position of H in the system has been a matter of some discussion, but it is not of much consequence. It seems to be rather an odd element. Perhaps the best place for it is in group IA as it forms a positive ion." (p. 350)

Thanks to Eric Scerri for the tip! 
See the website 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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