Periodic Table

The periodic table of the chemical elements reveals the organizing principles of matter, which is to say, the organizing principles of chemistry. The table is a tabular depiction of the chemical elements and their characteristics. Russian chemist Dmitri Mendeleev is generally credited with the invention of the periodic table.

The layout of the table has been refined and extended over time, as new elements have been discovered, and new theoretical models have been developed to explain chemical behavior.

The American Chemical Society presents two specific versions of the periodic table:

• The interactive periodic table on the ACS website encourages a “what’s this?” approach to exploration. It graphically highlights the various relationships among the elements. This periodic table appears courtesy of W. H. Freeman, publisher of Chemistry in the Community (a chemistry course for grades 9–12 developed by ACS) and CADRE design.
• Have you seen and chuckled at the Periodic Table of the Elephants and found yourself puzzled over the intended meaning behind any of the figures?