Chemical elements are substances composed of only one type of atom and they cannot be broken down further. Chemical elements are the simplest forms of matter and each one is assigned a specific atomic number. Check out these articles on chemical elements.


Iridium, a hard, white, metallic element of the platinum family. It is found in mineral deposits with platinum and osmium.

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  • Tin


    Tin, a chemical element that exists in two forms, one metallic and the other nonmetallic. See more »

  • Titanium


    Titanium, a lustrous, silvery-white, metallic chemical element. Titanium is soft, strong, lightweight, ductile (capable of being drawn into a thin wire), and corrosion-resistant, and can combine with many other metals to form alloys. See more »

  • Uranium


    Uranium, a radioactive, white, metallic element. It is the chief source of nuclear energy in nuclear power plants. See more »

  • Actinide Elements

    Actinide Elements

    Actinide Elements, or Actinides, a series of 15 chemical elements (atomic numbers 89 through 103). See more »

  • Actinium


    Actinium, a radioactive chemical element that occurs in nature in trace amounts as a result of the radioactive decay of uranium and thorium. See more »

  • Americium


    Americium, a radioactive chemical element. In pure form, it is a silvery metal. Americium does not occur in nature; it is artificially created. See more »

  • Antimony


    Antimony, a chemical element. It exists in two forms, one metallic and one nonmetallic. See more »

  • Argon


    Argon, a chemical element that is a colorless, odorless, tasteless gas at ordinary temperatures and pressures. See more »

  • Arsenic


    Arsenic, a chemical element. It can exist in several forms; these include metallic (or gray) arsenic and amorphous (or black) arsenic. See more »

  • Astatine


    Astatine, a radioactive chemical element. Astatine, a member of the halogen group of elements, is an extremely shortlived substance; its most stable isotope has a half-life period of only 8.3 hours. See more »

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