The chief commercial use of copper is based on its electrical conductivity (second only to that of silver); about half the total annual output of copper is employed in the manufacture of electrical apparatus and wire. Copper is also used extensively as roofing, in making copper utensils, and for coins and metalwork. Copper tubing is used in plumbing, and, because of its high heat conductivity, in heat-exchanging devices such as refrigerator and air-conditioner coils. Powdered copper is sometimes used as a pigment in paints. An important use of copper is in alloys such as brass, bronze, gunmetal, Monel metal, and German silver. Compounds of copper are widely used as insecticides and fungicides; as pigments in paints; as mordants (fixatives) in dyeing; and in electroplating.
2007-01-24 20:05:06
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answer #1
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answered by Kabir 2
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Conductor, thermal conductor, as a building material, and as a component of various alloys.
Copper has played a significant part in the history of mankind, which has used the easily accessible uncompounded metal for nearly 10,000 years. Civilizations in places like Iraq, China, Egypt, Greece and the Sumerian cities all have early evidence of using copper, and Britain and the United States also have extensive histories of copper use and mining. During the Roman Empire, copper was principally mined on Cyprus, hence the origin of the name of the metal as Cyprium, "metal of Cyprus", later shortened to Cuprum. A number of countries, such as Chile and the United States, still have sizeable reserves of the metal which are extracted through large open mines. Nevertheless, the price of copper rose rapidly—quintupling from a 60-year low in 1999—largely due to increased demand. This metal has come in to limelight on account of high volatility in prices.Copper occupies the same family of the periodic table as silver and gold, since they each have one S-orbital electron on top of a filled shell. This similarity in electron structure makes them similar in many characteristics. All have very high thermal and electrical conductivity, and all are malleable metals.
In its liquid state, a clear copper surface without ambient light appears somewhat greenish, another characteristic shared with gold. Silver does not have this property, so it is not a complementary color for the orange incandescence color. When liquid copper is in bright ambient light, it retains some of its pinkish luster. Due to its high surface tension, the liquid metal does not wetten surfaces but instead forms spherical droplets when poured on a surface.
Copper is insoluble in water (H2O) as well as in isopropanol.
There are two stable isotopes, 63Cu and 65Cu, along with a couple dozen radioisotopes. The vast majority of radioisotopes have half lives on the order of minutes or less; the longest lived, 64Cu, has a half life of 12.7 hours, with two decay modes leading to two separate products.
Numerous alloys of copper exist, many with important historical and contemporary uses. Speculum metal and bronze are alloys of copper and tin. Brass is an alloy of copper and zinc. Monel metal, also called cupronickel, is an alloy of copper and nickel. While the metal "bronze" usually refers to copper-tin alloys, it also is a generic term for any alloy of copper, such as aluminium bronze, silicon bronze, and manganese bronze.
The purity of copper is expressed as 4N for 99.99% pure or 7N for 99.99999% pure. The numeral gives the number of nines after the decimal point when expressed as a decimal (eg 4N means 0.9999, or 99.99%).
Copper wire.
Electromagnets.
Electrical machines, especially electromagnetic motors and generators.
Electrical relays, electrical busbars and electrical switches.
Vacuum tubes, cathode ray tubes, and the magnetrons in microwave ovens.
Wave guides for microwave radiation.
Integrated circuits, increasingly replacing aluminium because of its superior electrical conductivity.
As a material in the manufacture of computer heat sinks, as a result of its superior heat dissipation capacity to aluminium.
Copper roof on the Minneapolis City HallStructural Engineering:
Statuary: The Statue of Liberty, for example, contains 179,200 pounds (81.3 tonnes) of copper.
Alloyed with nickel, e.g. cupronickel and Monel, used as corrosive resistant materials in shipbuilding.
Watt's steam engine.
Household Products:
Copper plumbing fittings and compression tubes.
Doorknobs and other fixtures in houses.
Roofing, guttering, and rainspouts on buildings.
In cookware, such as frying pans.
Most flatware (knives, forks, spoons) contains some copper (nickel silver).
Sterling silver, if it is to be used in dinnerware, must contain a few percent copper.
Copper was sometimes used by the Inuit to make the cutting blade for ulus.
Copper water heating cylinders
Coinage:
As a component of coins, often as cupronickel alloy.
Euro coins contain different copper alloys
Since 1982, U.S. Pennies are 0.8% copper by weight (Balance zinc 99.2%).
U.S. Nickels are 75.0% copper by weight (Balance nickel 25.0%).
Since 1965, U.S. Dimes and Quarters are 91.67% copper by weight (Balance nickel 8.33%).
Biomedical applications:
As a biostatic surface in hospitals, and to line parts of ships to protect against barnacles and mussels, originally used pure, but superseded by Muntz Metal. Bacteria will not grow on a copper surface because it is biostatic. Copper doorknobs are used by hospitals to reduce the transfer of disease, and Legionnaires' disease is suppressed by copper tubing in air-conditioning systems.
Copper(II) sulfate is used as a fungicide and as algae control in domestic lakes and ponds. It is used in gardening powders and sprays to kill mildew.
Copper-62-PTSM, a complex containing radioactive copper-62, is used as a Positron emission tomography radiotracer for heart blood flow measurements.
Chemical applications:
Compounds, such as Fehling's solution, have applications in chemistry.
As a component in ceramic glazes, and to color glass.
Catalysis:
Used in the Water gas shift reaction which converts carbon monoxide into carbon dioxide.
Steam reforming which extracts hydrogen from hydrocarbons.
Others:
Musical instruments, especially brass instruments and cymbals.
2007-01-24 09:35:17
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answer #7
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answered by miley_fan9 3
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