Periodic Table
ALTERNATIVE NAME: Periodic Table of the Elements
DETAILS/DESCRIPTION:
The elements, such as hydrogen, sodium, and iron, are the building blocks of all physical matter. The Periodic Table is an orderly arrangement of these elements which allows us to see relationships between the elements.
If you read across the rows of the Periodic Table horizontally, the elements are arranged by ascending atomic weight, beginning with hydrogen at 1 in the upper left corner. The vertical columns are arranged so that elements with similar properties fall into the same column.
This arrangement was developed by Dmitri Mendeleyev* (1834-1907) and announced in 1869. Other people had produced different arrangements of the elements, but Mendeleyev's version had some notable improvements. He left gaps for "missing" elements and provided predictions on the qualities of the elements that he felt would be discovered to fill in these gaps.
These predictions were based on the periodicity (or regular pattern) that he saw when he wrote out his first chart.
Mendeleyev’s predictions turned out to be correct when additional elements were discovered.
ONELINER: The periodic table is a rows and columns arrangement of the chemical elements.
OTHER CONNECTIONS: It is widely used in chemistry, physics, and other sciences, and is generally seen as an icon of chemistry.
BIBLIOGRAPHY:
"Dmitri Mendeleev." Wikipedia. Last modified 23 Sept 2004. http://en.wikipedia.org/wiki/Dmitri_Ivanovich_Mendeleev Accessed September 27, 2004
"The Periodic Table." The Sciences Explorer, ThinkQuest '97. http://library.thinkquest.org/11771/english/hi/chemistry/periodic/primer.shtml Accessed September 27, 2004
AUDIO/VISUAL:
The Pictorial Periodic Table. http://chemlab.pc.maricopa.edu/periodic/foldedtable.html Accessed September 27, 2004. Includes various versions of the periodic table, including the original one created by Mendeleyev in 1869.
Portrait of Dmitry Mendeleyev by Ilya Repin, 1885. Olga's Gallery. http://www.abcgallery.com/R/repin/repin12.html Accessed September 27, 2004