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Ceramic

A ceramic is an inorganic, nonmetallic solid prepared by the action of heat and subsequent cooling.[1] Ceramic materials may have a crystalline or partly crystalline structure, or may be amorphous (e.g., a glass). Because most common ceramics are crystalline, the definition of ceramic is often restricted to inorganic crystalline materials, as opposed to the noncrystalline glasses. The earliest ceramics were pottery[citation needed] objects or 27,000 year old figurines made from clay, either by itself or mixed with other materials, hardened in fire. Later ceramics were glazed and fired to create a colored, smooth surface. Ceramics now include domestic, industrial and building products and art objects. In the 20th century, new ceramic materials were developed for use in advanced ceramic engineering; for example, in semiconductors. The word "ceramic" comes from the Greek word ? (keramikos), "of pottery" or "for pottery",[2] from ? (keramos), "potter's clay, tile, pottery".[3] The earliest mention of the root "ceram-" is the Mycenaean Greek ke-ra-me-we, "workers of ceramics", written in Linear B syllabic script.[4] "Ceramic" may be used as an adjective describing a material, product or process; or as a singular noun, or, more commonly, as a plural noun, "ceramics". Inorganic compounds are of inanimate, not biological, origin.[1] Inorganic compounds (except a limited number of carbon-containing compounds such as carbides, carbonates, simple oxides of carbon (such as CO and CO2), and cyanides, as well as the allotropes of carbon such as diam nd and graphite) lack carbon and hydrogen atoms and are synthesized by the agency of geological systems. In contrast, the synthesis of organic compounds in biological systems incorporates carbohydrates into the molecular structure. Organic chemists traditionally refer to any molecule containing carbon as an organic compound and by default this means that inorganic chemistry deals with molecules lacking carbon.[2] However, biologists may distinguish organic from inorganic compounds in a different way that does not hinge on the presence of a carbon atom. Pools of organic matter, for example, that have been metabolically incorporated into living tissues persist in decomposing tissues, but as molecules become oxidized into the open environment, such as atmospheric CO2, this creates a separate pool of inorganic compounds. The distinction between inorganic and organic compounds is not always clear when dealing with open and closed systems, because everything is ultimately connected to everything else on the planet. Some scientists, for example, view the open environment (i.e., the ecosphere) as an extension of life and from this perspective may consider atmospheric CO2 as an organic compound. IUPAC, an agency widely recognized for defining chemical terms, does not offer definitions of inorganic or organic. Hence, the definition for an inorganic versus an organic compound in a multidisciplinary context spans the division between living (or animate) and non-living (or inanimate) matter and remains open to debate according to the way that one views the world.

 
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