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: 1782 | PT id = 832, Type = element |
Discovery of Tellurium
Te
Tellurium, atomic number 52, has a mass of 127.6 au.
Tellurium caused great difficulty to the chemists who first tried to develop a periodic table, because it has an atomic weight greater than iodine (126.9). Mendeleev prioritised chemical properties over the anomalous atomic weight data, and correctly classified Te along with O, S, & Se. It was only when nuclear structure and the importance of atomic number was recognised, around 1918, that the issue was explained.
Tellurium was first isolated in 1782 by F.-J.M. von Reichenstein.
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| What is the Periodic Table Showing? | Periodicity |
© Mark R. Leach Ph.D. 1999 –
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