|The Elements Lithium (Li), Sodium (Na), and Potassium (K) all formed oxides in the ratio of two atoms per oxygen atom: R2O|
|The Elements Beryllium (Be), Magnesium (Mg), and Calcium (Ca) all formed oxides in the ratio of one atom per oxygen atom: RO|
|Boron (B) and Aluminum (Al) formed R2O3|
|Carbon (C) and Silicon (Si) formed RO2|
Recognizing the patterns of combining ratios or "valency", Mendeleev created a table organized by placing elements with similar combining ratios in the same group. He arranged the elements within a group in order of their atomic mass.
|In 1869, the Russian chemist Mendeleev noted that the repeating patterns of behavior could be arranged in a sequence of elements giving rise to the "Periodic Table" of the elements.|
Special thanks to Dr. Paul Karol's "Intro to Modern Chemistry" for providing much of the information on this page.
L O S
A L A M O S N A T I O N A L L A B O R A T O R Y
Operated by the University of California for the US Department of Energy
LANL External View | email@example.com | Help | Copyright © UC 1999 | Disclaimer