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: 1955 | PT id = 881, Type = element |
Discovery of Mendelevium
Md ![]()
Mendelevium, atomic number 101, has a mass of 258 au.
Synthetic radioactive element.
Mendelevium was first observed in 1955 by A. Ghiorso, G. Harvey, R. Choppin, S. G. Thompson and G. T. Seaborg.
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| What is the Periodic Table Showing? | Periodicity |
© Mark R. Leach Ph.D. 1999 –
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