In chemistry and atomic physics, main group elements are elements in groups (periodic columns) whose lightest members are represented by helium, lithium, beryllium, boron, carbon, nitrogen, oxygen, and fluorine as arranged in the periodic table of the elements. Main group elements include elements (except hydrogen) in groups 1 and 2 (s-block), and groups 13 to 18 (p-block). Group 12 elements are usually considered to be transition metals; however, zinc (Zn), cadmium (Cd), and mercury (Hg) share some properties of both groups, and some scientists believe they should be included as main group elements.
In older nomenclature the main group elements are groups IA and IIA, and groups IIIB to 0 (CAS groups IIIA to VIIIA).
Main group elements (with some of the lighter transition metals) are the most abundant elements on the earth, in the solar system, and in the universe. They are sometimes called the representative elements.
Famous quotes containing the words main, group and/or element:
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Struggling aloft unti it seems at rest
In the act of rising, until
The very wish of water is reversed,”
—Richard Wilbur (b. 1921)
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—Woodrow Wilson (1856–1924)
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—William Howard Taft (1857–1930)