|
This is a file from the Wikimedia Commons. Information from its description page there is shown below. Commons is a freely licensed media file repository. You can help.
|
Summary
Description |
English: Periodic Table, main "discovery periods"
|
Date |
2004 |
Source |
http://old.iupac.org/reports/periodic_table/index.html |
Author |
IUPAC |
Legend:
- Before 1800 (38 elements): discoveries during and before the age of enlightenment.
- 1800-1849 (+22 elements): science and industrial revolutions.
- 1850-1899 (+23 elements): the age of classifying elements recived the impulse of the spectrum analysis. Boisbaudran, Bunsen, Crookes, Kirchhoff, and others "hunting wikipedia:emission line signatures".
- 1900-1949 (+13 elements): impulse with the wikipedia:old quantum theory and wikipedia:quantum mechanics.
- 1950-present (+22 elements): "post atomic bomb" issues for atomic numbers 97 and above (colliders, bombardment techniques).
Licensing
|
The copyright holder of this file allows anyone to use it for any purpose, provided that the copyright holder is properly attributed. Redistribution, derivative work, commercial use, and all other use is permitted. |
Attribution
|
File usage
The following pages on Schools Wikipedia link to this image (list may be incomplete):
This file contains additional information, probably added from the digital camera or scanner used to create or digitize it. If the file has been modified from its original state, some details may not fully reflect the modified file.
Schools Wikipedia was created by children's charity SOS Children's Villages. The world's largest orphan charity, SOS Children's Villages brings a better life to more than 2 million people in 133 countries around the globe. We have helped children in Africa for many years - you can help too...