The periodic table's name comes from the fact that it arranges the elements into repeating sets, otherwise known as "periods." These periods are defined by the covalence of an element, the number of electrons it has in i... More »

The periodic table is useful because it identifies and arranges all known elements in an informative manner. Elements are arranged into periods and families. The elements in each family or period may have similar or diss... More »

The Periodic Table offers basic information about each one of the known chemical elements. Each element has its own box in the table, and these boxes include the element's atomic number, atomic weight and chemical symbol... More »

In a color-coded periodic table of the elements, the box for each element is colored. This color represents the classes of elements, which include metals, metalloids and non-metals. In general, the color blue is used for... More »

The periodic table was built to show the relationships among the various elements. The periodic table was constructed in 1869 by Dmitri Mendeleev. More »

Some elements on the periodic table are oxygen, helium, arsenic and fluorine. Oxygen is an odorless, tasteless and colorless gas at room temperature, but is bright blue as a liquid. Oxygen is a very reactive element and ... More »

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The periodic table was invented by chemist Dmitri Mendeleev to organize and compare elements and understand their relations with each other. Mendeleev created the periodic table between 1868 and 1870 while writing his bo... More »