|Appearance||red-orange metallic luster|
|Standard atomic weight Ar, std(Cu)||63.546(3)|
|Copper in the periodic table|
|Atomic number (Z)||29|
|Element category||transition metal|
|Electron configuration||[ Ar ] 3d10 4s1|
Electrons per shell
|2, 8, 18, 1|
|Phase at STP||solid|
|Melting point||1357.77 K (1084.62 °C,1984.32 °F)|
|Boiling point||2835 K(2562 °C,4643 °F)|
|Density (near r.t.)||8.96 g/cm3|
|when liquid (at m.p.)||8.02 g/cm3|
|Heat of fusion||13.26 kJ/mol|
|Heat of vaporization||300.4 kJ/mol|
|Molar heat capacity||24.440 J/(mol·K)|
| Vapor pressure |
|Oxidation states||−2, +1, +2, +3, +4 (a mildly basic oxide)|
|Electronegativity||Pauling scale: 1.90|
|Atomic radius||empirical:128 pm|
|Covalent radius||132±4 pm|
|Van der Waals radius||140 pm|
|Spectral lines of copper|
|Crystal structure|| face-centered cubic (fcc)|
|Speed of sound thin rod||(annealed)|
3810 m/s(at r.t.)
|Thermal expansion||16.5 µm/(m·K)(at 25 °C)|
|Thermal conductivity||401 W/(m·K)|
|Electrical resistivity||16.78 nΩ·m(at 20 °C)|
|Magnetic susceptibility||−5.46·10−6 cm3/mol|
|Young's modulus||110–128 GPa|
|Shear modulus||48 GPa|
|Bulk modulus||140 GPa|
|Vickers hardness||343–369 MPa|
|Brinell hardness||235–878 MPa|
|Naming||after Cyprus, principal mining place in Roman era (Cyprium)|
|Discovery||Middle East (9000 BC)|
|Main isotopes of copper|
Copper is a chemical element with symbol Cu (from Latin : cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and electricity, as a building material, and as a constituent of various metal alloys, such as sterling silver used in jewelry, cupronickel used to make marine hardware and coins, and constantan used in strain gauges and thermocouples for temperature measurement.
A chemical element is a species of atom having the same number of protons in their atomic nuclei. For example, the atomic number of oxygen is 8, so the element oxygen consists of all atoms which have exactly 8 protons.
The atomic number or proton number of a chemical element is the number of protons found in the nucleus of an atom. It is identical to the charge number of the nucleus. The atomic number uniquely identifies a chemical element. In an uncharged atom, the atomic number is also equal to the number of electrons.
Ductility is a measure of a material's ability to undergo significant plastic deformation before rupture, which may be expressed as percent elongation or percent area reduction from a tensile test. According to Shigley's Mechanical Engineering Design significant denotes about 5.0 percent elongation. See also Eq. 2–12, p. 50 for definitions of percent elongation and percent area reduction. Ductility is often characterized by a material's ability to be stretched into a wire.
Copper is one of the few metals that can occur in nature in a directly usable metallic form (native metals). This led to very early human use in several regions, from c. 8000 BC. Thousands of years later, it was the first metal to be smelted from sulfide ores, c. 5000 BC, the first metal to be cast into a shape in a mold, c. 4000 BC and the first metal to be purposefully alloyed with another metal, tin, to create bronze, c. 3500 BC.
A native metal is any metal that is found pure in its metallic form in nature. Metals that can be found as native deposits singly or in alloys include aluminium, antimony, arsenic, bismuth, cadmium, chromium, cobalt, indium, iron, manganese, molybdenum, nickel, niobium, rhenium, selenium, tantalum, tellurium, tin, titanium, tungsten, vanadium, and zinc, as well as two groups of metals: the gold group, and the platinum group. The gold group consists of gold, copper, lead, aluminium, mercury, and silver. The platinum group consists of platinum, iridium, osmium, palladium, rhodium, and ruthenium. Amongst the alloys found in native state have been brass, bronze, pewter, German silver, osmiridium, electrum, white gold, and silver-mercury and gold-mercury amalgam.
Smelting is a process of applying heat to ore in order to extract out a base metal. It is a form of extractive metallurgy. It is used to extract many metals from their ores, including silver, iron, copper, and other base metals. Smelting uses heat and a chemical reducing agent to decompose the ore, driving off other elements as gases or slag and leaving the metal base behind. The reducing agent is commonly a source of carbon, such as coke—or, in earlier times, charcoal.
Tin is a chemical element with the symbol Sn (from Latin: stannum) and atomic number 50. It is a post-transition metal in group 14 of the periodic table of elements. It is obtained chiefly from the mineral cassiterite, which contains stannic oxide, SnO2. Tin shows a chemical similarity to both of its neighbors in group 14, germanium and lead, and has two main oxidation states, +2 and the slightly more stable +4. Tin is the 49th most abundant element and has, with 10 stable isotopes, the largest number of stable isotopes in the periodic table, thanks to its magic number of protons. It has two main allotropes: at room temperature, the stable allotrope is β-tin, a silvery-white, malleable metal, but at low temperatures it transforms into the less dense grey α-tin, which has the diamond cubic structure. Metallic tin does not easily oxidize in air.
In the Roman era, copper was principally mined on Cyprus, the origin of the name of the metal, from aes сyprium (metal of Cyprus), later corrupted to сuprum (Latin), from which the words derived, coper (Old English) and copper, first used around 1530.
In historiography, ancient Rome is Roman civilization from the founding of the city of Rome in the 8th century BC to the collapse of the Western Roman Empire in the 5th century AD, encompassing the Roman Kingdom, Roman Republic and Roman Empire until the fall of the western empire. The civilization began as an Italic settlement in the Italian peninsula, dating from the 8th century BC, that grew into the city of Rome and which subsequently gave its name to the empire over which it ruled and to the widespread civilisation the empire developed. The Roman empire expanded to become one of the largest empires in the ancient world, though still ruled from the city, with an estimated 50 to 90 million inhabitants and covering 5.0 million square kilometres at its height in AD 117.
Cyprus, officially the Republic of Cyprus, is an island country in the Eastern Mediterranean and the third largest and third most populous island in the Mediterranean, located south of Turkey, west of Syria and Lebanon, northwest of Israel, north of Egypt, and southeast of Greece.
Old English, or Anglo-Saxon, is the earliest historical form of the English language, spoken in England and southern and eastern Scotland in the early Middle Ages. It was brought to Great Britain by Anglo-Saxon settlers probably in the mid-5th century, and the first Old English literary works date from the mid-7th century. After the Norman conquest of 1066, English was replaced, for a time, as the language of the upper classes by Anglo-Norman, a relative of French. This is regarded as marking the end of the Old English era, as during this period the English language was heavily influenced by Anglo-Norman, developing into a phase known now as Middle English.
The commonly encountered compounds are copper(II) salts, which often impart blue or green colors to such minerals as azurite, malachite, and turquoise, and have been used widely and historically as pigments.
Azurite is a soft, deep blue copper mineral produced by weathering of copper ore deposits. In the early 19th century, it was also known as chessylite after the type locality at Chessy-les-Mines near Lyon, France. The mineral, a carbonate with the chemical formula Cu3(CO3)2(OH)2, has been known since ancient times, and was mentioned in Pliny the Elder's Natural History under the Greek name kuanos (κυανός: "deep blue," root of English cyan) and the Latin name caeruleum. The blue of azurite is exceptionally deep and clear, and for that reason the mineral has tended to be associated since antiquity with the deep blue color of low-humidity desert and winter skies. The modern English name of the mineral reflects this association, since both azurite and azure are derived via Arabic from the Persian lazhward (لاژورد), an area known for its deposits of another deep blue stone, lapis lazuli ("stone of azure").
Malachite is a copper carbonate hydroxide mineral, with the formula Cu2CO3(OH)2. This opaque, green banded mineral crystallizes in the monoclinic crystal system, and most often forms botryoidal, fibrous, or stalagmitic masses, in fractures and spaces, deep underground, where the water table and hydrothermal fluids provide the means for chemical precipitation. Individual crystals are rare but do occur as slender to acicular prisms. Pseudomorphs after more tabular or blocky azurite crystals also occur.
Turquoise is an opaque, blue-to-green mineral that is a hydrated phosphate of copper and aluminium, with the chemical formula Cu Al6(PO4)4(OH)8·4H2O. It is rare and valuable in finer grades and has been prized as a gemstone and ornamental stone for thousands of years owing to its unique hue. In recent times, turquoise has been devalued, like most other opaque gems, by the introduction onto the market of treatments, imitations and synthetics.
Copper used in buildings, usually for roofing, oxidizes to form a green verdigris (or patina). Copper is sometimes used in decorative art, both in its elemental metal form and in compounds as pigments. Copper compounds are used as bacteriostatic agents, fungicides, and wood preservatives.
Verdigris is the common name for a green pigment obtained through the application of acetic acid to copper plates or the natural patina formed when copper, brass or bronze is weathered and exposed to air or seawater over time. It is usually a basic copper carbonate, but near the sea will be a basic copper chloride. If acetic acid is present at the time of weathering, it may consist of copper(II) acetate.
Patina is a thin layer that variously forms on the surface of copper, bronze and similar metals, or certain stones, and wooden furniture, or any similar acquired change of a surface through age and exposure.
A bacteriostatic agent or bacteriostat, abbreviated Bstatic, is a biological or chemical agent that stops bacteria from reproducing, while not necessarily killing them otherwise. Depending on their application, bacteriostatic antibiotics, disinfectants, antiseptics and preservatives can be distinguished. When bacteriostatic antimicrobials are used, the duration of therapy must be sufficient to allow host defense mechanisms to eradicate the bacteria. Upon removal of the bacteriostat, the bacteria usually start to grow again. This is in contrast to bactericides, which kill bacteria.
Copper is essential to all living organisms as a trace dietary mineral because it is a key constituent of the respiratory enzyme complex cytochrome c oxidase. In molluscs and crustaceans, copper is a constituent of the blood pigment hemocyanin, replaced by the iron-complexed hemoglobin in fish and other vertebrates. In humans, copper is found mainly in the liver, muscle, and bone. mg of copper per kilogram of body weight.The adult body contains between 1.4 and 2.1
The enzyme cytochrome c oxidase or Complex IV, EC 188.8.131.52 is a large transmembrane protein complex found in bacteria, archaea, and in eukaryotes in their mitochondria.
Hemocyanins (also spelled haemocyanins and abbreviated Hc) are proteins that transport oxygen throughout the bodies of some invertebrate animals. These metalloproteins contain two copper atoms that reversibly bind a single oxygen molecule (O2). They are second only to hemoglobin in frequency of use as an oxygen transport molecule. Unlike the hemoglobin in red blood cells found in vertebrates, hemocyanins are not bound to blood cells but are instead suspended directly in the hemolymph. Oxygenation causes a color change between the colorless Cu(I) deoxygenated form and the blue Cu(II) oxygenated form.
Hemoglobin (American) or haemoglobin (British), abbreviated Hb or Hgb, is the iron-containing oxygen-transport metalloprotein in the red blood cells (erythrocytes) of almost all vertebrates as well as the tissues of some invertebrates. Haemoglobin in the blood carries oxygen from the lungs or gills to the rest of the body. There it releases the oxygen to permit aerobic respiration to provide energy to power the functions of the organism in the process called metabolism. A healthy individual has 12 to 16 grams of haemoglobin in every 100 ml of blood.
Copper, silver, and gold are in group 11 of the periodic table; these three metals have one s-orbital electron on top of a filled d-electron shell and are characterized by high ductility, and electrical and thermal conductivity. The filled d-shells in these elements contribute little to interatomic interactions, which are dominated by the s-electrons through metallic bonds. Unlike metals with incomplete d-shells, metallic bonds in copper are lacking a covalent character and are relatively weak. This observation explains the low hardness and high ductility of single crystals of copper.At the macroscopic scale, introduction of extended defects to the crystal lattice, such as grain boundaries, hinders flow of the material under applied stress, thereby increasing its hardness. For this reason, copper is usually supplied in a fine-grained polycrystalline form, which has greater strength than monocrystalline forms.
The softness of copper partly explains its high electrical conductivity (59.6×106 S/m) and high thermal conductivity, second highest (second only to silver) among pure metals at room temperature. This is because the resistivity to electron transport in metals at room temperature originates primarily from scattering of electrons on thermal vibrations of the lattice, which are relatively weak in a soft metal. The maximum permissible current density of copper in open air is approximately 3.1×106 A/m2 of cross-sectional area, above which it begins to heat excessively.
Copper is one of a few metallic elements with a natural color other than gray or silver.Pure copper is orange-red and acquires a reddish tarnish when exposed to air. The characteristic color of copper results from the electronic transitions between the filled 3d and half-empty 4s atomic shells – the energy difference between these shells corresponds to orange light.
As with other metals, if copper is put in contact with another metal, galvanic corrosion will occur.
Copper does not react with water, but it does slowly react with atmospheric oxygen to form a layer of brown-black copper oxide which, unlike the rust that forms on iron in moist air, protects the underlying metal from further corrosion (passivation). A green layer of verdigris (copper carbonate) can often be seen on old copper structures, such as the roofing of many older buildingsand the Statue of Liberty. Copper tarnishes when exposed to some sulfur compounds, with which it reacts to form various copper sulfides.
There are 29 isotopes of copper. 63Cu and 65Cu are stable, with 63Cu comprising approximately 69% of naturally occurring copper; both have a spin of 3⁄2. The other isotopes are radioactive, with the most stable being 67Cu with a half-life of 61.83 hours. Seven metastable isotopes have been characterized; 68mCu is the longest-lived with a half-life of 3.8 minutes. Isotopes with a mass number above 64 decay by β−, whereas those with a mass number below 64 decay by β+. 64Cu, which has a half-life of 12.7 hours, decays both ways.
62Cu and 64Cu have significant applications. 62Cu is used in 62Cu-PTSM as a radioactive tracer for positron emission tomography.
Copper is produced in massive stars cm.and is present in the Earth's crust in a proportion of about 50 parts per million (ppm). In nature, copper occurs in a variety of minerals, including native copper, copper sulfides such as chalcopyrite, bornite, digenite, covellite, and chalcocite, copper sulfosalts such as tetrahedite-tennantite, and enargite, copper carbonates such as azurite and malachite, and as copper(I) or copper(II) oxides such as cuprite and tenorite, respectively. The largest mass of elemental copper discovered weighed 420 tonnes and was found in 1857 on the Keweenaw Peninsula in Michigan, US. Native copper is a polycrystal, with the largest single crystal ever described measuring 4.4×3.2×3.2
Most copper is mined or extracted as copper sulfides from large open pit mines in porphyry copper deposits that contain 0.4 to 1.0% copper. Sites include Chuquicamata, in Chile, Bingham Canyon Mine, in Utah, United States, and El Chino Mine, in New Mexico, United States. According to the British Geological Survey, in 2005, Chile was the top producer of copper with at least one-third of the world share followed by the United States, Indonesia and Peru.Copper can also be recovered through the in-situ leach process. Several sites in the state of Arizona are considered prime candidates for this method. The amount of copper in use is increasing and the quantity available is barely sufficient to allow all countries to reach developed world levels of usage.
Copper has been in use at least 10,000 years, but more than 95% of all copper ever mined and smelted has been extracted since 1900,and more than half was extracted the last 24 years. As with many natural resources, the total amount of copper on Earth is vast, with around 1014 tons in the top kilometer of Earth's crust, which is about 5 million years' worth at the current rate of extraction. However, only a tiny fraction of these reserves is economically viable with present-day prices and technologies. Estimates of copper reserves available for mining vary from 25 to 60 years, depending on core assumptions such as the growth rate. Recycling is a major source of copper in the modern world. Because of these and other factors, the future of copper production and supply is the subject of much debate, including the concept of peak copper, analogous to peak oil.
The price of copper has historically been unstable, [ better source needed ] In February 2009, weakening global demand and a steep fall in commodity prices since the previous year's highs left copper prices at $1.51/lb ($3.32/kg).and its price increased from the 60-year low of US$0.60/lb (US$1.32/kg) in June 1999 to $3.75 per pound ($8.27/kg) in May 2006. It dropped to $2.40/lb ($5.29/kg) in February 2007, then rebounded to $3.50/lb ($7.71/kg) in April 2007.
The concentration of copper in ores averages only 0.6%, and most commercial ores are sulfides, especially chalcopyrite (CuFeS2), bornite (Cu5FeS4) and, to a lesser extent, covellite (CuS) and chalcocite (Cu2S).These minerals are concentrated from crushed ores to the level of 10–15% copper by froth flotation or bioleaching. Heating this material with silica in flash smelting removes much of the iron as slag. The process exploits the greater ease of converting iron sulfides into oxides, which in turn react with the silica to form the silicate slag that floats on top of the heated mass. The resulting copper matte, consisting of Cu2S, is roasted to convert all sulfides into oxides:
The cuprous oxide is converted to blister copper upon heating:
The Sudbury matte process converted only half the sulfide to oxide and then used this oxide to remove the rest of the sulfur as oxide. It was then electrolytically refined and the anode mud exploited for the platinum and gold it contained. This step exploits the relatively easy reduction of copper oxides to copper metal. Natural gas is blown across the blister to remove most of the remaining oxygen and electrorefining is performed on the resulting material to produce pure copper:
Like aluminium, kg. Much of this is in more-developed countries (140–300 kg per capita) rather than less-developed countries (30–40 kg per capita).copper is recyclable without any loss of quality, both from raw state and from manufactured products. In volume, copper is the third most recycled metal after iron and aluminium. An estimated 80% of all copper ever mined is still in use today. According to the International Resource Panel's Metal Stocks in Society report, the global per capita stock of copper in use in society is 35–55
The process of recycling copper is roughly the same as is used to extract copper but requires fewer steps. High-purity scrap copper is melted in a furnace and then reduced and cast into billets and ingots; lower-purity scrap is refined by electroplating in a bath of sulfuric acid.
Numerous copper alloys have been formulated, many with important uses. Brass is an alloy of copper and zinc. Bronze usually refers to copper-tin alloys, but can refer to any alloy of copper such as aluminium bronze. Copper is one of the most important constituents of silver and karat gold solders used in the jewelry industry, modifying the color, hardness and melting point of the resulting alloys.Some lead-free solders consist of tin alloyed with a small proportion of copper and other metals.
The alloy of copper and nickel, called cupronickel, is used in low-denomination coins, often for the outer cladding. The US five-cent coin (currently called a nickel) consists of 75% copper and 25% nickel in homogeneous composition. The alloy of 90% copper and 10% nickel, remarkable for its resistance to corrosion, is used for various objects exposed to seawater, though it is vulnerable to the sulfides sometimes found in polluted harbors and estuaries.Alloys of copper with aluminium (about 7%) have a golden color and are used in decorations. Shakudō is a Japanese decorative alloy of copper containing a low percentage of gold, typically 4–10%, that can be patinated to a dark blue or black color.
Copper forms a rich variety of compounds, usually with oxidation states +1 and +2, which are often called cuprous and cupric, respectively.Copper compounds, whether organic complexes or organometallics, promote or catalyse numerous chemical and biological processes.
As with other elements, the simplest compounds of copper are binary compounds, i.e. those containing only two elements, the principal examples being oxides, sulfides, and halides. Both cuprous and cupric oxides are known. Among the numerous copper sulfides, important examples include copper(I) sulfide and copper(II) sulfide.
Cuprous halides (with chlorine, bromine, and iodine) are known, as are cupric halides with fluorine, chlorine, and bromine. Attempts to prepare copper(II) iodide yield only cuprous iodide and iodine.
Copper forms coordination complexes with ligands. In aqueous solution, copper(II) exists as [Cu(H2O)6]2+. This complex exhibits the fastest water exchange rate (speed of water ligands attaching and detaching) for any transition metal aquo complex. Adding aqueous sodium hydroxide causes the precipitation of light blue solid copper(II) hydroxide. A simplified equation is:
Aqueous ammonia results in the same precipitate. Upon adding excess ammonia, the precipitate dissolves, forming tetraamminecopper(II):
Many other oxyanions form complexes; these include copper(II) acetate, copper(II) nitrate, and copper(II) carbonate. Copper(II) sulfate forms a blue crystalline pentahydrate, the most familiar copper compound in the laboratory. It is used in a fungicide called the Bordeaux mixture.
Polyols, compounds containing more than one alcohol functional group, generally interact with cupric salts. For example, copper salts are used to test for reducing sugars. Specifically, using Benedict's reagent and Fehling's solution the presence of the sugar is signaled by a color change from blue Cu(II) to reddish copper(I) oxide.Schweizer's reagent and related complexes with ethylenediamine and other amines dissolve cellulose. Amino acids form very stable chelate complexes with copper(II). Many wet-chemical tests for copper ions exist, one involving potassium ferrocyanide, which gives a brown precipitate with copper(II) salts.
Compounds that contain a carbon-copper bond are known as organocopper compounds. They are very reactive towards oxygen to form copper(I) oxide and have many uses in chemistry. They are synthesized by treating copper(I) compounds with Grignard reagents, terminal alkynes or organolithium reagents;in particular, the last reaction described produces a Gilman reagent. These can undergo substitution with alkyl halides to form coupling products; as such, they are important in the field of organic synthesis. Copper(I) acetylide is highly shock-sensitive but is an intermediate in reactions such as the Cadiot-Chodkiewicz coupling and the Sonogashira coupling. Conjugate addition to enones and carbocupration of alkynes can also be achieved with organocopper compounds. Copper(I) forms a variety of weak complexes with alkenes and carbon monoxide, especially in the presence of amine ligands.
Copper(III) is most often found in oxides. A simple example is potassium cuprate, KCuO2, a blue-black solid.The most extensively studied copper(III) compounds are the cuprate superconductors. Yttrium barium copper oxide (YBa2Cu3O7) consists of both Cu(II) and Cu(III) centres. Like oxide, fluoride is a highly basic anion and is known to stabilize metal ions in high oxidation states. Both copper(III) and even copper(IV) fluorides are known, K3CuF6 and Cs2CuF6, respectively.
Some copper proteins form oxo complexes, which also feature copper(III).With tetrapeptides, purple-colored copper(III) complexes are stabilized by the deprotonated amide ligands.
Complexes of copper(III) are also found as intermediates in reactions of organocopper compounds.For example, in the Kharasch–Sosnovsky reaction.
A timeline of copper illustrates how the metal has advanced human civilization for the past 11,000 years.
Copper occurs naturally as native metallic copper and was known to some of the oldest civilizations on record. The history of copper use dates to 9000 BC in the Middle East;a copper pendant was found in northern Iraq that dates to 8700 BC. Evidence suggests that gold and meteoric iron (but not smelted iron) were the only metals used by humans before copper. The history of copper metallurgy is thought to follow this sequence: First, cold working of native copper, then annealing, smelting, and, finally, lost-wax casting. In southeastern Anatolia, all four of these techniques appear more or less simultaneously at the beginning of the Neolithic c. 7500 BC.
Copper smelting was independently invented in different places. It was probably discovered in China before 2800 BC, in Central America around 600 AD, and in West Africa about the 9th or 10th century AD.Investment casting was invented in 4500–4000 BC in Southeast Asia and carbon dating has established mining at Alderley Edge in Cheshire, UK, at 2280 to 1890 BC. Ötzi the Iceman, a male dated from 3300–3200 BC, was found with an axe with a copper head 99.7% pure; high levels of arsenic in his hair suggest an involvement in copper smelting. Experience with copper has assisted the development of other metals; in particular, copper smelting led to the discovery of iron smelting. Production in the Old Copper Complex in Michigan and Wisconsin is dated between 6000 and 3000 BC. Natural bronze, a type of copper made from ores rich in silicon, arsenic, and (rarely) tin, came into general use in the Balkans around 5500 BC.
Alloying copper with tin to make bronze was first practiced about 4000 years after the discovery of copper smelting, and about 2000 years after "natural bronze" had come into general use.Bronze artifacts from the Vinča culture date to 4500 BC. Sumerian and Egyptian artifacts of copper and bronze alloys date to 3000 BC. The Bronze Age began in Southeastern Europe around 3700–3300 BC, in Northwestern Europe about 2500 BC. It ended with the beginning of the Iron Age, 2000–1000 BC in the Near East, and 600 BC in Northern Europe. The transition between the Neolithic period and the Bronze Age was formerly termed the Chalcolithic period (copper-stone), when copper tools were used with stone tools. The term has gradually fallen out of favor because in some parts of the world, the Chalcolithic and Neolithic are coterminous at both ends. Brass, an alloy of copper and zinc, is of much more recent origin. It was known to the Greeks, but became a significant supplement to bronze during the Roman Empire.
In Greece, copper was known by the name chalkos (χαλκός). It was an important resource for the Romans, Greeks and other ancient peoples. In Roman times, it was known as aes Cyprium, aes being the generic Latin term for copper alloys and Cyprium from Cyprus, where much copper was mined. The phrase was simplified to cuprum, hence the English copper. Aphrodite (Venus in Rome) represented copper in mythology and alchemy because of its lustrous beauty and its ancient use in producing mirrors; Cyprus was sacred to the goddess. The seven heavenly bodies known to the ancients were associated with the seven metals known in antiquity, and Venus was assigned to copper.
Copper was first used in ancient Britain in about the 3rd or 2nd century BC. In North America, copper mining began with marginal workings by Native Americans. Native copper is known to have been extracted from sites on Isle Royale with primitive stone tools between 800 and 1600.Copper metallurgy was flourishing in South America, particularly in Peru around 1000 AD. Copper burial ornamentals from the 15th century have been uncovered, but the metal's commercial production did not start until the early 20th century.
The cultural role of copper has been important, particularly in currency. Romans in the 6th through 3rd centuries BC used copper lumps as money. At first, the copper itself was valued, but gradually the shape and look of the copper became more important. Julius Caesar had his own coins made from brass, while Octavianus Augustus Caesar's coins were made from Cu-Pb-Sn alloys. With an estimated annual output of around 15,000 t, Roman copper mining and smelting activities reached a scale unsurpassed until the time of the Industrial Revolution; the provinces most intensely mined were those of Hispania, Cyprus and in Central Europe.
The gates of the Temple of Jerusalem used Corinthian bronze treated with depletion gilding.[ clarification needed ][ citation needed ] The process was most prevalent in Alexandria, where alchemy is thought to have begun. In ancient India, copper was used in the holistic medical science Ayurveda for surgical instruments and other medical equipment. Ancient Egyptians (~2400 BC) used copper for sterilizing wounds and drinking water, and later to treat headaches, burns, and itching.
The Great Copper Mountain was a mine in Falun, Sweden, that operated from the 10th century to 1992. It satisfied two thirds of Europe's copper consumption in the 17th century and helped fund many of Sweden's wars during that time.It was referred to as the nation's treasury; Sweden had a copper backed currency.
Copper is used in roofing,currency, and for photographic technology known as the daguerreotype. Copper was used in Renaissance sculpture, and was used to construct the Statue of Liberty; copper continues to be used in construction of various types. Copper plating and copper sheathing were widely used to protect the under-water hulls of ships, a technique pioneered by the British Admiralty in the 18th century. The Norddeutsche Affinerie in Hamburg was the first modern electroplating plant, starting its production in 1876. The German scientist Gottfried Osann invented powder metallurgy in 1830 while determining the metal's atomic mass; around then it was discovered that the amount and type of alloying element (e.g., tin) to copper would affect bell tones. Flash smelting was developed by Outokumpu in Finland and first applied at Harjavalta in 1949; the energy-efficient process accounts for 50% of the world's primary copper production.
The Intergovernmental Council of Copper Exporting Countries, formed in 1967 by Chile, Peru, Zaire and Zambia, operated in the copper market as OPEC does in oil, though it never achieved the same influence, particularly because the second-largest producer, the United States, was never a member; it was dissolved in 1988.
The major applications of copper are electrical wire (60%), roofing and plumbing (20%), and industrial machinery (15%). Copper is used mostly as a pure metal, but when greater hardness is required, it is put into such alloys as brass and bronze (5% of total use).For more than two centuries, copper paint has been used on boat hulls to control the growth of plants and shellfish. A small part of the copper supply is used for nutritional supplements and fungicides in agriculture. Machining of copper is possible, although alloys are preferred for good machinability in creating intricate parts.
Despite competition from other materials, copper remains the preferred electrical conductor in nearly all categories of electrical wiring except overhead electric power transmission where aluminium is often preferred.Copper wire is used in power generation, power transmission, power distribution, telecommunications, electronics circuitry, and countless types of electrical equipment. Electrical wiring is the most important market for the copper industry. This includes structural power wiring, power distribution cable, appliance wire, communications cable, automotive wire and cable, and magnet wire. Roughly half of all copper mined is used for electrical wire and cable conductors. Many electrical devices rely on copper wiring because of its multitude of inherent beneficial properties, such as its high electrical conductivity, tensile strength, ductility, creep (deformation) resistance, corrosion resistance, low thermal expansion, high thermal conductivity, ease of soldering, malleability, and ease of installation.
For a short period from the late 1960s to the late 1970s, copper wiring was replaced by aluminium wiring in many housing construction projects in America. The new wiring was implicated in a number of house fires and the industry returned to copper.
Integrated circuits and printed circuit boards increasingly feature copper in place of aluminium because of its superior electrical conductivity; heat sinks and heat exchangers use copper because of its superior heat dissipation properties. Electromagnets, vacuum tubes, cathode ray tubes, and magnetrons in microwave ovens use copper, as do waveguides for microwave radiation.
Copper's superior conductivity enhances the efficiency of electrical motors.This is important because motors and motor-driven systems account for 43%–46% of all global electricity consumption and 69% of all electricity used by industry. Increasing the mass and cross section of copper in a coil increases the efficiency of the motor. Copper motor rotors, a new technology designed for motor applications where energy savings are prime design objectives, are enabling general-purpose induction motors to meet and exceed National Electrical Manufacturers Association (NEMA) premium efficiency standards.
Copper has been used since ancient times as a durable, corrosion resistant, and weatherproof architectural material.Roofs, flashings, rain gutters, downspouts, domes, spires, vaults, and doors have been made from copper for hundreds or thousands of years. Copper's architectural use has been expanded in modern times to include interior and exterior wall cladding, building expansion joints, radio frequency shielding, and antimicrobial and decorative indoor products such as attractive handrails, bathroom fixtures, and counter tops. Some of copper's other important benefits as an architectural material include low thermal movement, light weight, lightning protection, and recyclability
The metal's distinctive natural green patina has long been coveted by architects and designers. The final patina is a particularly durable layer that is highly resistant to atmospheric corrosion, thereby protecting the underlying metal against further weathering.It can be a mixture of carbonate and sulfate compounds in various amounts, depending upon environmental conditions such as sulfur-containing acid rain. Architectural copper and its alloys can also be 'finished' to take on a particular look, feel, or color. Finishes include mechanical surface treatments, chemical coloring, and coatings.
Copper has excellent brazing and soldering properties and can be welded; the best results are obtained with gas metal arc welding.
Copper is biostatic, meaning bacteria and many other forms of life will not grow on it. For this reason it has long been used to line parts of ships to protect against barnacles and mussels. It was originally used pure, but has since been superseded by Muntz metal and copper-based paint. Similarly, as discussed in copper alloys in aquaculture, copper alloys have become important netting materials in the aquaculture industry because they are antimicrobial and prevent biofouling, even in extreme conditionsand have strong structural and corrosion-resistant properties in marine environments.
Copper-alloy touch surfaces have natural properties that destroy a wide range of microorganisms (e.g., E. coli O157:H7, methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus , Clostridium difficile , influenza A virus, adenovirus, and fungi). [ clarification needed ] were proven to kill more than 99.9% of disease-causing bacteria within just two hours when cleaned regularly. The United States Environmental Protection Agency (EPA) has approved the registrations of these copper alloys as "antimicrobial materials with public health benefits"; that approval allows manufacturers to make legal claims to the public health benefits of products made of registered alloys. In addition, the EPA has approved a long list of antimicrobial copper products made from these alloys, such as bedrails, handrails, over-bed tables, sinks, faucets, door knobs, toilet hardware, computer keyboards, health club equipment, and shopping cart handles (for a comprehensive list, see: Antimicrobial copper-alloy touch surfaces#Approved products). Copper doorknobs are used by hospitals to reduce the transfer of disease, and Legionnaires' disease is suppressed by copper tubing in plumbing systems. Antimicrobial copper alloy products are now being installed in healthcare facilities in the U.K., Ireland, Japan, Korea, France, Denmark, and Brazil[ citation needed ] and in the subway transit system in Santiago, Chile, where copper-zinc alloy handrails will be installed in some 30 stations between 2011 and 2014. Textile fibers can be blended with copper to create antimicrobial protective fabrics.Some 355 copper alloys
Copper may be used as a speculative investment due to the predicted increase in use from worldwide infrastructure growth, and the important role it has in producing wind turbines, solar panels, and other renewable energy sources .Another reason predicted demand increases is the fact that electric cars contain an average of 3.6 times as much copper as conventional cars, although the effect of electric cars on copper demand is debated. Some people invest in copper through copper mining stocks, ETFs, and futures. Others store physical copper in the form of copper bars or rounds although these tend to carry a higher premium in comparison to precious metals. Those who want to avoid the premiums of copper bullion alternatively store old copper wire, copper tubing or american [[Penny (United States Coin)|pennies made before 1982].
Copper is commonly used in jewelry, and according to some folklore, copper bracelets relieve arthritis symptoms.In one trial for osteoarthritis and one trial for rheumatoid arthritis no differences is found between copper bracelet and control (non-copper) bracelet. No evidence shows that copper can be absorbed through the skin. If it were, it might lead to copper poisoning.
Recently, some compression clothing with inter-woven copper has been marketed with health claims similar to the folk medicine claims. Because compression clothing is a valid treatment for some ailments, the clothing may have that benefit, but the added copper may have no benefit beyond a placebo effect.
Chromobacterium violaceum and Pseudomonas fluorescens can both mobilize solid copper as a cyanide compound.The ericoid mycorrhizal fungi associated with Calluna, Erica and Vaccinium can grow in metalliferous soils containing copper. The ectomycorrhizal fungus Suillus luteus protects young pine trees from copper toxicity. A sample of the fungus Aspergillus niger was found growing from gold mining solution and was found to contain cyano complexes of such metals as gold, silver, copper, iron, and zinc. The fungus also plays a role in the solubilization of heavy metal sulfides.
Copper proteins have diverse roles in biological electron transport and oxygen transportation, processes that exploit the easy interconversion of Cu(I) and Cu(II).Copper is essential in the aerobic respiration of all eukaryotes. In mitochondria, it is found in cytochrome c oxidase, which is the last protein in oxidative phosphorylation. Cytochrome c oxidase is the protein that binds the O2 between a copper and an iron; the protein transfers 8 electrons to the O2 molecule to reduce it to two molecules of water. Copper is also found in many superoxide dismutases, proteins that catalyze the decomposition of superoxides by converting it (by disproportionation) to oxygen and hydrogen peroxide:
The protein hemocyanin is the oxygen carrier in most mollusks and some arthropods such as the horseshoe crab (Limulus polyphemus).Because hemocyanin is blue, these organisms have blue blood rather than the red blood of iron-based hemoglobin. Structurally related to hemocyanin are the laccases and tyrosinases. Instead of reversibly binding oxygen, these proteins hydroxylate substrates, illustrated by their role in the formation of lacquers. The biological role for copper commenced with the appearance of oxygen in earth's atmosphere. Several copper proteins, such as the "blue copper proteins", do not interact directly with substrates; hence they are not enzymes. These proteins relay electrons by the process called electron transfer.
A unique tetranuclear copper center has been found in nitrous-oxide reductase.
Chemical compounds which were developed for treatment of Wilson's disease have been investigated for use in cancer therapy.
Copper is an essential trace element in plants and animals, but not all microorganisms. The human body contains copper at a level of about 1.4 to 2.1 mg per kg of body mass. Copper is absorbed in the gut, then transported to the liver bound to albumin. After processing in the liver, copper is distributed to other tissues in a second phase, which involves the protein ceruloplasmin, carrying the majority of copper in blood. Ceruloplasmin also carries the copper that is excreted in milk, and is particularly well-absorbed as a copper source. Copper in the body normally undergoes enterohepatic circulation (about 5 mg a day, vs. about 1 mg per day absorbed in the diet and excreted from the body), and the body is able to excrete some excess copper, if needed, via bile, which carries some copper out of the liver that is not then reabsorbed by the intestine.
The U.S. Institute of Medicine (IOM) updated the estimated average requirements (EARs) and recommended dietary allowances (RDAs) for copper in 2001. If there is not sufficient information to establish EARs and RDAs, an estimate designated Adequate Intake (AI) is used instead. The AIs for copper are: 200 μg of copper for 0–6-month-old males and females, and 220 μg of copper for 7–12-month-old males and females. The RDAs for copper are: 340 μg of copper for 1–3-year-old males, 440 μg of copper for 4–8-year-old males, 700 μg of copper for 9–13-year-old males, 890 μg of copper for 14–18-year-old males, and 900 μg of copper for males that are 19 years old and older. The RDAs for copper are: 340 μg of copper for 1–3-year-old females, 440 μg of copper for 4–8-year-old females, 700 μg of copper for 9–13-year-old females, 890 μg of copper for 14–18-year-old females, and 900 μg of copper for females that are 19 years old and older. The RDAs for copper are: 1,000 μg of copper for 14–50-year-old pregnant females; furthermore, 1,300 μg of copper for 14–50-year-old lactating females. As for safety, the IOM also sets Tolerable upper intake levels (ULs) for vitamins and minerals when evidence is sufficient. In the case of copper the UL is set at 10 mg/day. Collectively the EARs, RDAs, AIs and ULs are referred to as Dietary Reference Intakes.
The European Food Safety Authority (EFSA) refers to the collective set of information as Dietary Reference Values, with Population Reference Intake (PRI) instead of RDA, and Average Requirement instead of EAR. AI and UL defined the same as in United States. For women and men ages 18 and older the AIs are set at 1.3 and 1.6 mg/day, respectively. AIs for pregnancy and lactation is 1.5 mg/day. For children ages 1–17 years the AIs increase with age from 0.7 to 1.3 mg/day. These AIs are higher than the U.S. RDAs. The European Food Safety Authority reviewed the same safety question and set its UL at 5 mg/day, which is half the U.S. value.
For U.S. food and dietary supplement labeling purposes the amount in a serving is expressed as a percent of Daily Value (%DV). For copper labeling purposes 100% of the Daily Value was 2.0 mg, but as of May 27,2016 [update] it was revised to 0.9 mg to bring it into agreement with the RDA. A table of the old and new adult Daily Values is provided at Reference Daily Intake. The original deadline to be in compliance was July 28, 2018, but on September 29, 2017 the FDA released a proposed rule that extended the deadline to January 1, 2020 for large companies and January 1, 2021 for small companies.
Because of its role in facilitating iron uptake, copper deficiency can produce anemia-like symptoms, neutropenia, bone abnormalities, hypopigmentation, impaired growth, increased incidence of infections, osteoporosis, hyperthyroidism, and abnormalities in glucose and cholesterol metabolism. Conversely, Wilson's disease causes an accumulation of copper in body tissues.
Severe deficiency can be found by testing for low plasma or serum copper levels, low ceruloplasmin, and low red blood cell superoxide dismutase levels; these are not sensitive to marginal copper status. The "cytochrome c oxidase activity of leucocytes and platelets" has been stated as another factor in deficiency, but the results have not been confirmed by replication.
Gram quantities of various copper salts have been taken in suicide attempts and produced acute copper toxicity in humans, possibly due to redox cycling and the generation of reactive oxygen species that damage DNA. mg/kg) are toxic in animals. A minimum dietary value for healthy growth in rabbits has been reported to be at least 3 ppm in the diet. However, higher concentrations of copper (100 ppm, 200 ppm, or 500 ppm) in the diet of rabbits may favorably influence feed conversion efficiency, growth rates, and carcass dressing percentages.Corresponding amounts of copper salts (30
Chronic copper toxicity does not normally occur in humans because of transport systems that regulate absorption and excretion. Autosomal recessive mutations in copper transport proteins can disable these systems, leading to Wilson's disease with copper accumulation and cirrhosis of the liver in persons who have inherited two defective genes.
Elevated copper levels have also been linked to worsening symptoms of Alzheimer's disease.
In the US, the Occupational Safety and Health Administration (OSHA) has designated a permissible exposure limit (PEL) for copper dust and fumes in the workplace as a time-weighted average (TWA) of 1 mg/m3. The National Institute for Occupational Safety and Health (NIOSH) has set a Recommended exposure limit (REL) of 1 mg/m3, time-weighted average. The IDLH (immediately dangerous to life and health) value is 100 mg/m3.
Copper is a constituent of tobacco smoke.The tobacco plant readily absorbs and accumulates heavy metals, such as copper from the surrounding soil into its leaves. These are readily absorbed into the user's body following smoke inhalation. The health implications are not clear.
Antimony is a chemical element with symbol Sb (from Latin: stibium) and atomic number 51. A lustrous gray metalloid, it is found in nature mainly as the sulfide mineral stibnite (Sb2S3). Antimony compounds have been known since ancient times and were powdered for use as medicine and cosmetics, often known by the Arabic name, kohl. Metallic antimony was also known, but it was erroneously identified as lead upon its discovery. The earliest known description of the metal in the West was written in 1540 by Vannoccio Biringuccio.
Barium is a chemical element with symbol Ba and atomic number 56. It is the fifth element in group 2 and is a soft, silvery alkaline earth metal. Because of its high chemical reactivity, barium is never found in nature as a free element. Its hydroxide, known in pre-modern times as baryta, does not occur as a mineral, but can be prepared by heating barium carbonate.
Chromium is a chemical element with symbol Cr and atomic number 24. It is the first element in group 6. It is a steely-grey, lustrous, hard and brittle transition metal. Chromium boasts a high usage rate as a metal that is able to be highly polished while resisting tarnishing. Chromium is also the main additive in stainless steel, a popular steel alloy due to its uncommonly high specular reflection. Simple polished chromium reflects almost 70% of the visible spectrum, with almost 90% of infrared light being reflected. The name of the element is derived from the Greek word χρῶμα, chrōma, meaning color, because many chromium compounds are intensely colored.
Cadmium is a chemical element with symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Like zinc, it demonstrates oxidation state +2 in most of its compounds, and like mercury, it has a lower melting point than the transition metals in groups 3 through 11. Cadmium and its congeners in group 12 are often not considered transition metals, in that they do not have partly filled d or f electron shells in the elemental or common oxidation states. The average concentration of cadmium in Earth's crust is between 0.1 and 0.5 parts per million (ppm). It was discovered in 1817 simultaneously by Stromeyer and Hermann, both in Germany, as an impurity in zinc carbonate.
Magnesium is a chemical element with symbol Mg and atomic number 12. It is a shiny gray solid which bears a close physical resemblance to the other five elements in the second column of the periodic table: all group 2 elements have the same electron configuration in the outer electron shell and a similar crystal structure.
Manganese is a chemical element with symbol Mn and atomic number 25. It is not found as a free element in nature; it is often found in minerals in combination with iron. Manganese is a metal with important industrial metal alloy uses, particularly in stainless steels.
Molybdenum is a chemical element with symbol Mo and atomic number 42. The name is from Neo-Latin molybdaenum, from Ancient Greek Μόλυβδος molybdos, meaning lead, since its ores were confused with lead ores. Molybdenum minerals have been known throughout history, but the element was discovered in 1778 by Carl Wilhelm Scheele. The metal was first isolated in 1781 by Peter Jacob Hjelm.
Nickel is a chemical element with symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile. Pure nickel, powdered to maximize the reactive surface area, shows a significant chemical activity, but larger pieces are slow to react with air under standard conditions because an oxide layer forms on the surface and prevents further corrosion (passivation). Even so, pure native nickel is found in Earth's crust only in tiny amounts, usually in ultramafic rocks, and in the interiors of larger nickel–iron meteorites that were not exposed to oxygen when outside Earth's atmosphere.
Palladium is a chemical element with symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by William Hyde Wollaston. He named it after the asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired by her when she slew Pallas. Palladium, platinum, rhodium, ruthenium, iridium and osmium form a group of elements referred to as the platinum group metals (PGMs). These have similar chemical properties, but palladium has the lowest melting point and is the least dense of them.
Thallium is a chemical element with symbol Tl and atomic number 81. It is a gray post-transition metal that is not found free in nature. When isolated, thallium resembles tin, but discolors when exposed to air. Chemists William Crookes and Claude-Auguste Lamy discovered thallium independently in 1861, in residues of sulfuric acid production. Both used the newly developed method of flame spectroscopy, in which thallium produces a notable green spectral line. Thallium, from Greek θαλλός, thallós, meaning "a green shoot or twig", was named by Crookes. It was isolated by both Lamy and Crookes in 1862; Lamy by electrolysis, and Crookes by precipitation and melting of the resultant powder. Crookes exhibited it as a powder precipitated by zinc at the International exhibition, which opened on 1 May that year.
Vanadium is a chemical element with symbol V and atomic number 23. It is a hard, silvery-grey, ductile, malleable transition metal. The elemental metal is rarely found in nature, but once isolated artificially, the formation of an oxide layer (passivation) somewhat stabilizes the free metal against further oxidation.
Zinc is a chemical element with symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. In some respects zinc is chemically similar to magnesium: both elements exhibit only one normal oxidation state (+2), and the Zn2+ and Mg2+ ions are of similar size. Zinc is the 24th most abundant element in Earth's crust and has five stable isotopes. The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The largest workable lodes are in Australia, Asia, and the United States. Zinc is refined by froth flotation of the ore, roasting, and final extraction using electricity (electrowinning).
Sulfide (British English sulphide) is an inorganic anion of sulfur with the chemical formula S2− or a compound containing one or more S2− ions. Solutions of sulfide salts are corrosive. Sulfide also refers to chemical compounds large families of inorganic and organic compounds, e.g. lead sulfide and dimethyl sulfide. Hydrogen sulfide (H2S) and bisulfide (SH-) are the conjugate acids of sulfide.
Group 12, by modern IUPAC numbering, is a group of chemical elements in the periodic table. It includes zinc (Zn), cadmium (Cd) and mercury (Hg). The further inclusion of copernicium (Cn) in group 12 is supported by recent experiments on individual copernicium atoms. Formerly this group was named IIB by CAS and old IUPAC system.
Copper extraction refers to the methods used to obtaining copper from its ores. The conversion of copper consists of a series of physical and electrochemical processes. Methods have evolved and vary with country depending on the ore source, local environmental regulations, and other factors.
Copper monosulfide is a chemical compound of copper and sulfur. It occurs in nature as the dark indigo blue mineral covellite. It is a moderate conductor of electricity. A black colloidal precipitate of CuS is formed when hydrogen sulfide, H2S, is bubbled through solutions of Cu(II) salts. It is one of a number of binary compounds of copper and sulfur (see copper sulfide for an overview of this subject), and has attracted interest because of its potential uses in catalysis and photovoltaics.
Copper sulfides describe a family of chemical compounds and minerals with the formula CuSy. Both minerals and synthetic materials comprise these compounds. Some copper sulfides are economically important ores.
Pure gold is slightly reddish yellow in color, but colored gold in various other colors can be produced.
Cobalt is a chemical element with symbol Co and atomic number 27. Like nickel, cobalt is found in the Earth's crust only in chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal.
|in pure water, or acidic or alkali conditions. Copper in neutral water is more noble than hydrogen.||in water containing sulfide||in 10 M ammonia solution||in a chloride solution|
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