nonmetal

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Related to Non-metals: Metalloids

nonmetal,

chemical elementelement,
in chemistry, a substance that cannot be decomposed into simpler substances by chemical means. A substance such as a compound can be decomposed into its constituent elements by means of a chemical reaction, but no further simplification can be achieved.
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 possessing certain properties by which it is distinguished from a metalmetal,
chemical element displaying certain properties by which it is normally distinguished from a nonmetal, notably its metallic luster, the capacity to lose electrons and form a positive ion, and the ability to conduct heat and electricity.
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. In general, this distinction is drawn on the basis that a nonmetal tends to accept electrons and form negative ionsion,
atom or group of atoms having a net electric charge. Positive and Negative Electric Charges

A neutral atom or group of atoms becomes an ion by gaining or losing one or more electrons or protons.
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 and that its oxide is acidic. Nonmetals are poor conductors of heat and electricity (see conductionconduction,
transfer of heat or electricity through a substance, resulting from a difference in temperature between different parts of the substance, in the case of heat, or from a difference in electric potential, in the case of electricity.
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) and do not have the luster of metals. Arsenic, antimony, selenium, and tellurium exhibit both nonmetallic and metallic properties and are called metalloids. Unlike the metals, which are all solids (with the exception of mercury) under ordinary conditions of temperature and pressure, the nonmetals appear in all three states. Argon, chlorine, fluorine, helium, hydrogen, krypton, neon, nitrogen, oxygen, and xenon are normally gases. Bromine is a liquid. Boron, carbon, iodine, phosphorus, silicon, and sulfur are solids. Certain of them, e.g., boron, carbon, iodine, silicon, and sulfur, form crystals, as do the metals. In hardness they vary considerably. Carbon in its allotropic form, the diamond, is the hardest element known. With the exception of carbon, sulfur, nitrogen, oxygen, and the inert gases—argon, helium, krypton, neon, and xenon—the nonmetals do not occur uncombined in nature, but exist in numerous relatively abundant compounds, among which are the oxides, halides (binary halogen compounds), sulfides, carbonates, nitrates, phosphates, silicates, and sulfates. With a few exceptions, the nonmetallic elements are important chiefly for their compounds. For the properties and uses of specific nonmetals, see the separate articles on these elements.

nonmetal

any of a number of chemical elements that form negative ions, have acidic oxides, and are generally poor conductors of heat and electricity
References in periodicals archive ?
The conditions in this level include uncomplicated metal shapes (no non-metal substrates of significance); few colors to meet most of demand; the level of smoothness (orange peel, appearance) was acceptable; relatively wide variations of dry film thicknesses were ok--1.
The conditions at this level include; more complicated metal shapes (Faraday Cage)--still little non-metal substrates; more numerous color change demand (capital investment); smoother films are required (higher cost powder coatings and handling system); there is more stringent film thickness control; and toughness remains as powders core strength.
Supplier awards were granted for: metals, non-metals, electronics, non-production goods and services, transportation and recognizing an exemplary minority supplier from North America.
Invitation to tender: atomic spectrophotometer with flame and graphite furnace for testing residues and heavy metal content and non-metals, in accordance with technical specification
The plant includes a pre-washer followed by two Steinert eddy currents and a media drum that uses magnetite to separate the remaining metals from non-metals.
ADS enhances its supply chain management application, LoMaS(R), to include "shopping cart" load building and non-metals commodities functionality for CSG at the Port of Leetsdale, Pennsylvania
Even though modifying LoMaS(R) to accommodate other non-metal commodities was not a priority or plan, ADS has always known that such enhancements could be easily accomplished," stated Gordy Gustafson, Vice President - Integrated Solutions division for ADS.
The City of Tempe is issuing this Request for Proposal (RFP) to establish contracts for analytical testing of water, wastewater, solid wastes, and special projects for: nutrients, biologicals, metals, non-metals, organics, and radio chemicals with qualified licensed environmental laboratories.
This technology enables the efficient extraction and recovery of metals and non-metals from ore.
This investment was the largest single portion of our remaining non-metals assets.
The operating performance at major properties improved by the fourth quarter, and the Company made good progress on developing a strong earnings stream from non-metals businesses and disposing of non-strategic businesses.
Biochemists and other scientists from the chemical or biological hinterlands describe some recent developments in remediating non-metal pollutants in soil, ground water, and marine environments.