Periodic Table

The periodic table presents the elements arranged in atomic number order. Elements are organized in periodic groups based on the number of valence electrons of the element, and are classified as metals, nonmetals, and metalloids. It was Dmitrii Mendeleev and Lothar Meyer who created and published the first successful periodic tables in 1870, although they had worked independently of each other. Mendeleev based his table on chemical properties; Meyer, on physical properties. Mendeleev proposed a table with columns of related elements, yet his table was incomplete; he intentionally neglected to fill each space. These voids, however, eventually lead to the discovery of new elements. Put simply, Mendeleev accurately predicted the properties of the undiscovered elements, realizing the periodic relationships of the elements around them on this table. As a result, the periodic table is an organizational tool and an important source of information about each element, as well as the trends of the elements.

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INSTRUCTIONS

  1. Elemental Properties
    A variety of commonly studied properties of the elements are available for examination using this computerized periodic table. The characteristics of each element can be obtained by one of four methods:
    1. Click on the element in the periodic table.
    2. Type the name of the element in the text box and press return.
    3. Type the element's symbol in the box and press return.
    4. Type the element's atomic number in the box and press return.

  2. The elemental properties to be examined include:
    Atomic Weight Ionization Energy Density
    Covalent Radii Melting Point Ionic Radii
    Boiling Point Isotopes Electron Affinity
    Common Charges Electronegativity

  3. Periodic Trends

Last modified: April 13, 2000