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单词 copper
释义
copper

Chemistry
  • A red-brown transition element; a.n. 29; r.a.m. 63.546; r.d. 8.92; m.p. 1083.4°C; b.p. 2567°C. Copper has been extracted for thousands of years; it was known to the Romans as cuprum, a name linked with the island of Cyprus. The metal is malleable and ductile and an excellent conductor of heat and electricity. Copper-containing minerals include cuprite (Cu2O) as well as azurite (2CuCO3.Cu(OH)2), chalcopyrite (CuFeS2), and malachite (CuCO3.Cu(OH)2). Native copper appears in isolated pockets in some parts of the world. The large mines in the USA, Chile, Canada, Zambia, Democratic Republic of Congo, and Peru extract ores containing sulphides, oxides, and carbonates. They are usually worked by smelting, leaching, and electrolysis. Copper metal is used to make electric cables and wires. Its alloys, brass (copper-zinc) and bronze (copper-tin), are used extensively.

    Water does not attack copper but in moist atmospheres it slowly forms a characteristic green surface layer (patina). The metal will not react with dilute sulphuric or hydrochloric acids, but with nitric acid oxides of nitrogen are formed. Copper compounds contain the element in the +1 and +2 oxidation states. Copper(I) compounds are mostly white (the oxide is red). Copper(II) salts are blue in solution. The metal also forms a large number of coordination complexes. It is thought that the characteristic colour of copper is due to overlapping energy bands.

    https://www.webelements.com/copper/ Information from the WebElements site


Chemical Engineering
  • A valuable metal noted for its high electrical conductivity, malleability, suitability as an alloy with other metals, and resistance to corrosion. It is extracted from various ores by crushing and ball milling, followed by flotation separation to raise the copper content, and remove unwanted minerals. Smelting with sulphur then produces copper and iron sulphide. This is melted in a reverbatory furnace in which air (oxygen) is added to produce sulphur dioxide, iron, and copper. The copper is then electrolytically refined to produce commercial copper. Copper has many uses in the process industry in addition to electrical wiring. It is also used for small bore pipes and for copper stills in the whisky industry.


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