copper

29nickelcopperzinc
-

Cu

Ag
General
Name, symbol, numbercopper, Cu, 29
Chemical seriestransition metals
Group, period, block114, d
Appearancemetallic pinkish red
Standard atomic weight63.546(3) gmol−1
Electron configuration[Ar] 3d10 4s1
Electrons per shell2, 8, 18, 1
Physical properties
Phasesolid
Density (near r.t.)8.96 gcm−3
Liquid density at m.p.8.02 gcm−3
Melting point1357.77 K
(1084.62 °C, 1984.32 °F)
Boiling point2835 K
(2562 °C, 4643 °F)
Heat of fusion13.26 kJmol−1
Heat of vaporization300.4 kJmol−1
Heat capacity(25 C) 24.440 Jmol−1K−1
Vapor pressure
P/Pa1101001 k10 k100 k
at T/K150916611850208924042836
Atomic properties
Crystal structureface centered cubic
Oxidation states2, 1
(mildly basic oxide)
Electronegativity1.90 (Pauling scale)
Ionization energies
(more)
1st: 745.5 kJmol−1
2nd: 1957.9 kJmol−1
3rd: 3666 kJmol−1
Atomic radius135 pm
Atomic radius (calc.)145 pm
Covalent radius138 pm
Van der Waals radius140 pm
Magnetic orderingdiamagnetic
Electrical resistivity(20 C) 16.78 nΩm
Thermal conductivity(300 K) 401 Wm−1K−1
Thermal expansion(25 C) 16.5 µmm−1K−1
Speed of sound (thin rod)(r.t.) (annealed)
3810 ms−1
Young's modulus110 - 128 GPa
Shear modulus48 GPa
Selected isotopes
Main article: Isotopes of copper
iso NA half-life DM DE (MeV) DP

63Cu69.15%Cu is stable with 34 neutrons
65Cu30.85%Cu is stable with 36 neutrons
References
This box:     [ edit]
Copper (IPA: /ˈkɒpə/, /ˈkɑpəɹ/) is a chemical element in the periodic table that has the symbol Cu (Latin: cuprum) and atomic number 29. It is a ductile metal with excellent electrical conductivity, and finds extensive use as an electrical conductor, heat conductor, as a building material, and as a component of various alloys.

Copper is an essential trace nutrient to all high plants and animals. In animals, including humans, it is found primarily in the bloodstream, as a co-factor in various enzymes, and in copper-based pigments. However, in sufficient amounts, copper can be poisonous and even fatal to organisms.

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 such as Iraq, China, Egypt, Greece and the Sumerian cities all have early evidence of using copper. 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 sizable reserves of the metal which are extracted through large open pit mines. Nevertheless, the price of copper has risen rapidly, increasing 500% from a 60-year low in 1999, largely due to increased demand. The Earth has an estimated 61 years of copper reserves remaining.[1]

Notable characteristics

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Copper just above its melting point keeps its pink luster color when enough light outshines the orange incandescence color.
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Copper exists as a metallically bonded substance, allowing it to have a wide variety of metallic properties.

Conductivity

Copper has a high electrical and thermal conductivity, second only to silver among pure metals at room temperature. [2]

Color

Copper is a reddish-colored metal, it has its characteristic color because it reflects red and orange light and absorbs other frequencies in the visible spectrum, due to its band structure.

In its liquefied state, a pure copper surface without ambient light appears somewhat greenish, a characteristic shared with gold. When liquid copper is in bright ambient light, it retains some of its pinkish luster.

Location in the periodic table

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 electron 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.

Corrosion properties

Pure water and air

Copper is a metal that does not react with water (H2O), but the oxygen of the air will react slowly at room temperature to form a layer of copper oxide on copper metal.

It can be seen that copper in "pure" water is more noble than hydrogen. As a result it does not corrode in oxygen free water and the corrosion rate in oxygenated water is low.



It is important to note that in contrast to the oxidation of iron by wet air that the layer formed by the reaction of air with copper has a protective effect against further corrosion. On old copper roofs a green layer of copper carbonate can often be seen.

Sulphide media

Copper metal does react with hydrogen sulphide and sulfide containing solutions. A series of different copper sulphides can form on the surface of the copper metal.



Note that the copper sulphide area of the plot is very complex due to the existance of many different sulphides, a close up is also provided to make the graph more clear. It is clear that the copper is now able to corrode even without the need for oxygen as the copper is now less noble than hydrogen. This can be observed in every day life when copper metal surfaces tarnish after exposure to air which contains sulfur compounds.

Ammonia media

Copper does react with oxygen-containing ammonia solutions because the ammonia forms water-soluble copper complexes. The formation of these complexes causes the corrosion to become more thermodynamically favoured than the corrosion of copper in an identical solution that does not contain the ammonia.

Chloride media

Copper does react with a combination of oxygen and hydrochloric acid to form a series of copper chlorides. It is interesting to note that if copper(II) chloride (green/blue) is boiled with copper metal (with little or no oxygen present) then white copper(I) chloride will be formed.

Isotopes

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, 67Cu, has a half life of 61.8 hours. See also isotopes of copper.

Alloys

Numerous copper alloys 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.

Germicidal effect

Copper is germicidal, via the oligodynamic effect. For example, brass doorknobs disinfect themselves of many bacteria within a period of eight hours.[8] This effect is useful in many applications.

Applications

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Native copper specimen (~ 4 cm in size)
Copper is malleable and ductile, a good conductor of heat and, when very pure, a good conductor of electricity.

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 (e.g. 4N means 0.9999, or 99.99%).

It is used extensively, in products such as:

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Copper piping system with intumescent firestop being installed by an insulator in Vancouver, Canada.

Piping

  • including, but not limited to, extreme water supply.

Electronics

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Copper roof on the Minneapolis City Hall, coated with Patina

Architecture

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Old copper utensils in a Jerusalem restaurant

Household Products

Coinage

Biomedical applications

Chemical applications

Other

History

Copper, as native copper, is one of the few metals to naturally occur as an uncompounded mineral. Copper was known to some of the oldest civilizations on record, and has a history of use that is at least 10,000 years old. A copper pendant was found in what is now northern Iraq that dates to 8700 BC. By 5000 BC, there are signs of copper smelting, the refining of copper from simple copper compounds such as malachite or azurite. Among archaeological sites in Anatolia, Çatal Höyük (~6000 BC) features native copper artifacts and smelted lead beads, but no smelted copper. But Can Hasan (~5000 BC) had access to smelted copper; this site has yielded the oldest known cast copper artifact, a copper mace head.
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Ancient Copper ingot from Zakros, Crete is shaped in the form of an animal skin typical for that era.


Copper smelting appears to have been developed independently in several parts of the world. In addition to its development in Anatolia by 5000 BC, it was developed in China before 2800 BC, in the Andes around 2000 BC, in Central America around 600 AD, and in West Africa around 900 AD.[16] Copper is found extensively in the Indus Valley Civilization by the 3rd millennium BC.[17] In Europe, Ötzi the Iceman, a well-preserved male dated to 3200 BC, was found with a copper-tipped axe whose metal was 99.7% pure. High levels of arsenic in his hair suggest he was involved in copper smelting. There are copper and bronze artifacts from Sumerian cities that date to 3000 BC, and Egyptian artifacts of copper and copper-tin alloys nearly as old. In one pyramid, a copper plumbing system was found that is 5000 years old. The Egyptians found that adding a small amount of tin made the metal easier to cast, so bronze alloys were found in Egypt almost as soon as copper was found. In the Americas production in the Old Copper Complex, located in present day Michigan and Wisconsin, was dated back to between 6000 to 3000 BC.[18]

The use of bronze became so pervasive in a certain era of civilization that it has been named the Bronze Age. The transitional period in certain regions between the preceding Neolithic period and the Bronze Age is termed the Chalcolithic ("copper-stone"), with some high-purity copper tools being used alongside stone tools. Brass was known to the Greeks, but only became a significant supplement to bronze during the Roman empire.

In Greek the metal was known by the name chalkos (χαλκός). Copper was a very important resource for the Romans, Greeks and other ancient peoples. In Roman times, it became known as aes Cyprium (aes being the generic Latin term for copper alloys such as bronze and other metals, and Cyprium because so much of it was mined in Cyprus). From this, the phrase was simplified to cuprum and then eventually Anglicized into the English copper. Copper was associated with the goddess Aphrodite/Venus in mythology and alchemy, owing to its lustrous beauty, its ancient use in producing mirrors, and its association with Cyprus, which was sacred to the goddess.

Copper mining in Britain and the United States

See Copper extraction for the article on copper mining techniques.
Copper has been mined for many centuries. By 2000 BC, Europe was using copper-tin alloys or ‘bronze’. The Bronze Age is taken as 2500 BC to 600 BC.

Britain and Ireland

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West Mine at Alderley Edge
During the Bronze Age, copper was mined in Britain and Ireland mainly in the following locations: At Great Orme in North Wales, such working extended for a depth of 70 metres.[19] At Alderley Edge in Cheshire, carbon dates have established mining at around 2280 to 1890 BC (at 95% probability).[20]

United States

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Miners at the Tamarack Mine in Copper Country, Michigan, USA in 1905.
Copper mining in the United States began with marginal workings by Native Americans and some development by early Spaniards. Europeans were mining copper in Connecticut as early as 1709. Perhaps the oldest operating large-scale copper mine was the historic Elizabeth Mine in Vermont. Dating to the 1700s, "the Liz" produced copper until it was closed in 1958. Westward movement also brought an expansion of copper exploitation with developments of significant deposits in Michigan and Arizona during the 1850s and then in Montana during the 1860s.

Copper was mined extensively in Michigan's Keweenaw Peninsula with the heart of extraction at the productive Quincy Mine. Arizona had many notable deposits including the Copper Queen in Bisbee and the United Verde in Jerome. The Anaconda in Butte, Montana became the nation's chief copper supplier by 1886.

Copper is mined in many other areas of the United States, including Utah, Nevada and Tennessee. Copper is the state mineral for Utah.

Biological role

Copper is essential in all plants and animals. Copper is carried mostly in the bloodstream on a plasma protein called ceruloplasmin. When copper is first absorbed in the gut it is transported to the liver bound to albumin. Copper is found in a variety of enzymes, including the copper centers of cytochrome c oxidase and the enzyme superoxide dismutase (containing copper and zinc). In addition to its enzymatic roles, copper is used for biological electron transport. The blue copper proteins that participate in electron transport include azurin and plastocyanin. The name "blue copper" comes from their intense blue color arising from a ligand-to-metal charge transfer (LMCT) absorption band around 600 nm.

Most molluscs and some arthropods such as the horseshoe crab use the copper-containing pigment hemocyanin rather than iron-containing hemoglobin for oxygen transport, so their blood is blue when oxygenated rather than red.[21]

It is believed that zinc and copper compete for absorption in the digestive tract so that a diet that is excessive in one of these minerals may result in a deficiency in the other. The RDA for copper in normal healthy adults is 0.9 mg/day. Because of its role in facilitating iron uptake, copper deficiency can often produce anemia-like symptoms.

Toxicity

All copper compounds, unless otherwise known, should be treated as if they were toxic. Thirty grams of copper sulfate is potentially lethal in humans. The suggested safe level of copper in drinking water for humans varies depending on the source, but tends to be pegged at 1.5 to 2 mg/L. The DRI Tolerable Upper Intake Level for adults of dietary copper from all sources is 10 mg/day. In toxicity, copper can inhibit the enzyme dihydrophil hydratase, an enzyme involved in haemopoiesis.

Symptoms of copper poisoning are very similar to those produced by arsenic. Fatal cases are generally terminated by convulsions, palsy, and insensibility.

In cases of suspected copper poisoning, Ovalbumin is to be administered in either of its forms which can be most readily obtained, as milk or whites of eggs. Vinegar should not be given. The inflammatory symptoms are to be treated on general principles, and so are the nervous.

A significant portion of the toxicity of copper comes from its ability to accept and donate single electrons as it changes oxidation state. This catalyzes the production of very reactive radical ions such as hydroxyl radical in a manner similar to fenton chemistry.[22] This catalytic activity of copper is used by the enzymes that it is associated with and is thus only toxic when unsequestered and unmediated. This increase in unmediated reactive radicals is generally termed oxidative stress and is an active area of research in a variety of diseases where copper may play an important but more subtle role than in acute toxicity.

An inherited condition called Wilson's disease causes the body to retain copper, since it is not excreted by the liver into the bile. This disease, if untreated, can lead to brain and liver damage. In addition, studies have found that people with mental illnesses such as schizophrenia had heightened levels of copper in their systems. However it is unknown at this stage whether the copper contributes to the mental illness, whether the body attempts to store more copper in response to the illness, or whether the high levels of copper are the result of the mental illness.

Too much copper in water has also been found to damage marine life. The observed effect of these higher concentrations on fish and other creatures is damage to gills, liver, kidneys, and the nervous system. It also interferes with the sense of smell in fish, thus preventing them from choosing good mates or finding their way to mating areas.

Miscellaneous hazards

The metal, when powdered, is a fire hazard. At concentrations higher than 1 mg/L, copper can stain clothes and items washed in water.

Occurrence

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Chuquicamata (Chile). One of the largest open pit copper mines in the world.
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Copper output in 2005
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World production trend
Main article: Copper extraction
In 2005, Chile was the top mine producer of copper with at least one-third world share followed by the USA, Indonesia and Peru, reports the British Geological Survey.

Copper can be found as native copper in mineral form. Minerals such as the sulfides: chalcopyrite (CuFeS2), bornite (Cu5FeS4), covellite (CuS), chalcocite (Cu2S) are sources of copper, as are the carbonates: azurite (Cu3(CO3)2(OH)2) and malachite (Cu2CO3(OH)2) and the oxide: cuprite (Cu2O).

Most copper ore is mined or extracted as copper sulfides from large open pit mines in porphyry copper deposits that contain 0.4 to 1.0 percent copper. Examples include: Chuquicamata in Chile and El Chino Mine in New Mexico. The average abundance of copper found within crustal rocks is approximately 68 ppm by mass, and 22 ppm by atoms.
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Native Copper Placer Nuggets
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Native copper


The Intergovernmental Council of Copper Exporting Countries (CIPEC), defunct since 1992, once tried to play a similar role for copper as OPEC does for oil, but never achieved the same influence, not least because the second-largest producer, the United States, was never a member. Formed in 1967, its principal members were Chile, Peru, Zaire, and Zambia.

The copper price has quintupled since 1999, rising from $0.60 per pound in June 1999 to $3.75 per pound in May 2006, where it dropped to $2.40 in February 2007 then rebounded to $3.50 in April 2007.[23]

Compounds

Common oxidation states of copper include the less stable copper(I) state, Cu+; and the more stable copper(II) state, Cu2+, which forms blue or blue-green salts and solutions. Under unusual conditions, a 3+ state and even an extremely rare 4+ state can be obtained. Using old nomenclature for the naming of salts, copper(I) is called cuprous, and copper(II) cupric. In oxidation copper is mildly basic.

Copper(II) carbonate is green from which arises the unique appearance of copper-clad roofs or domes on some buildings. Copper(II) sulfate forms a blue crystalline pentahydrate which is perhaps the most familiar copper compound in the laboratory. It is used as a fungicide, known as Bordeaux mixture.

There are two stable copper oxides, copper(II) oxide (CuO) and copper(I) oxide (Cu2O). Copper oxides are used to make yttrium barium copper oxide (YBa2Cu3O7-δ) or YBCO which forms the basis of many unconventional superconductors. Copper(I) and copper(II) can also be referred to by their common names cuprous and cupric.

See also:

Tests for copper(II) ion

Add aqueous sodium hydroxide. A blue precipitate of copper(II) hydroxide should form.

Ionic equation:

Cu2+(aq) + 2OH(aq) → Cu(OH)2(s)


The full equation shows that the reaction is due to hydroxide ions deprotonating the hexaaquacopper (II) complex:

[Cu(H2O)6]2+(aq) + 2 OH(aq) → Cu(H2O)4(OH)2(s) + 2 H2O (l)


Adding aqueous ammonia causes the same precipitate to form. It then dissolves upon adding excess ammonia, to form a deep blue ammonia complex, tetraamminecopper(II).

Ionic equation:

Cu(H2O)4(OH)2(s) + 4 NH3(aq) → [Cu(H2O)2(NH3)4]2+(aq) + 2H2O(l) + 2 OH(aq)


A more delicate test than the ammonia is the ferrocyanide of potassium, which gives a brown precipitate with copper salts.

See also

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Evolution of the historical copper price
source : minerals.usgs.gov (XLS)
Current price is at least four times higher than the 2002 value.

References

1. ^ New Scientist. May 26, 2007.
2. ^ Los Alamos National Laboratory - Copper
3. ^ Ignasi Puigdomenech, Hydra/Medusa Chemical Equilibrium Database and Plotting Software (2004) KTH Royal Institute of Technology, freely downloadable software at [1]
4. ^ Ignasi Puigdomenech, Hydra/Medusa Chemical Equilibrium Database and Plotting Software (2004) KTH Royal Institute of Technology, freely downloadable software at [2]
5. ^ Ignasi Puigdomenech, Hydra/Medusa Chemical Equilibrium Database and Plotting Software (2004) KTH Royal Institute of Technology, freely downloadable software at [3]
6. ^ Ignasi Puigdomenech, Hydra/Medusa Chemical Equilibrium Database and Plotting Software (2004) KTH Royal Institute of Technology, freely downloadable software at [4]
7. ^ Ignasi Puigdomenech, Hydra/Medusa Chemical Equilibrium Database and Plotting Software (2004) KTH Royal Institute of Technology, freely downloadable software at [5]
8. ^ Phyllis J. Kuhn, Ph.D. (1983). Doorknobs: A Source of Nosocomial Infection?. Retrieved on 2007-08-15.
9. ^ Berg, Jan. Why did we paint the library's roof?. Retrieved on 2007-09-20.
10. ^ Copper Development Association, UK
11. ^ US Mint specifications.
12. ^ Royal (i.e. United Kingdom) Mint specifications.
13. ^ Royal Australian Mint specifications.
14. ^ Change For The Better/Q & A/Technical Questions
15. ^ Cupron Antimicrobial
16. ^ Richard Cowen, Essays on Geology, History, and People, Chapter 3: "Fire and Metals: Copper".
17. ^ harappa.com (Web archive)
18. ^ Thomas C. Pleger, Ph.D. (2000). The Old Copper Complex of the Western Great Lakes. UW-Fox Valley Anthropology. Retrieved on 2007-08-15.
19. ^ O’Brien, W. (1997). Bronze Age Copper Mining in Britain and Ireland. Shire Publications Ltd. ISBN 0747803218. 
20. ^ Timberlake and Prag, 2005
21. ^ Horseshoe Crab Fun Facts NOAA and Univ. of Delaware
22. ^ Held KD et al. (May 1996). "Role of Fenton chemistry in thiol-induced toxicity and apoptosis". Radiat Res. 145 (5): 542–53. 
23. ^ Copper Trends: Live Metal Spot Prices, MetalSpotPrice.com

Further reading

External links

2, 3
(mildly basic oxide)
Electronegativity 1.91 (Pauling scale)
Ionization energies
(more) 1st: 737.1 kJmol−1
2nd: 1753.0 kJmol−1
3rd: 3395 kJmol−1

Atomic radius 135 pm
Atomic radius (calc.
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Zinc (IPA: /ˈzɪŋk/, from German: Zink) is a chemical element in the periodic table that has the symbol Zn and atomic number 30.
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Silver (IPA: /ˈsɪlvə(ɹ)/) is a chemical element with the symbol Ag (Latin: argentum) and atomic number 47.
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An extended periodic table was suggested by Glenn T. Seaborg in 1969. It is a logical extension of the principles behind the standard periodic table to include possible undiscovered chemical elements.
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<onlyinclude> This is a list of chemical elements, sorted by name and color coded according to type of element.

Given is each element's element symbol, atomic number, atomic mass or most stable isotope, and group and period numbers on the periodic table.
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<onlyinclude> This is a list of chemical elements by symbol, including the current signification used to identify the chemical elements as recognized by the International Union of Pure and Applied Chemistry, as well as proposed and historical signs.
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A table of chemical elements ordered by atomic number and color coded according to type of element. Given is each element's name, element symbol, group and period, Chemical series, and atomic mass (or most stable isotope).
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A group, also known as a family, is a vertical column in the periodic table of the chemical elements. There are 18 groups in the standard periodic table.

The modern explanation of the pattern of the periodic table is that the elements in a group have similar
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In chemistry, the term transition metal (sometimes also called a transition element) has two possible meanings:
  • It commonly refers to any element in the d-block of the periodic table, including zinc, cadmium and mercury.

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A group, also known as a family, is a vertical column in the periodic table of the chemical elements. There are 18 groups in the standard periodic table.

The modern explanation of the pattern of the periodic table is that the elements in a group have similar
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Periods:]] 1 2 3 4 5 6 7 8
Series Alkalis Alkaline earths Lanthanides Actinides Transition metals Poor metals Metalloids Nonmetals Halogens Noble gases
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A block of the periodic table of elements is a set of adjacent groups. The respective highest-energy electrons in each element in a block belong to the same atomic orbital type.
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A Group 11 element is one in the series of elements in group 11 (IUPAC style) in the periodic table, consisting of transition metals which are the traditional coinage metals of copper (Cu), silver (Ag), and gold (Au).
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A period 4 element is one of the chemical elements in the fourth row (or period) of the periodic table of the elements.

These are: Chemical elements in the fourth period
Group 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Atomic number
Name 19
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D-Block is an American rap group founded in the 1990s by Sheek Louch, Jadakiss and Styles P as The Lox or The L.O.X.. [1] In 2001 the group renamed themselves from "The Lox" to "D-Block".
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Color or colour[1] (see spelling differences) is the visual perceptual property corresponding in humans to the categories called red, yellow, blue, black, etc.
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atomic mass (ma) is the mass of an atom at rest, most often expressed in unified atomic mass units.[1] The atomic mass may be considered to be the total mass of protons, neutrons and electrons in a single atom (when the atom is motionless).
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To help compare different orders of magnitude, the following list describes various mass levels between 10−36 kg and 1053 kg.

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electron configuration is the arrangement of electrons in an atom, molecule, or other physical structure (e.g., a crystal). Like other elementary particles, the electron is subject to the laws of quantum mechanics, and exhibits both particle-like and wave-like nature.
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Argon (IPA:/ˈɑːgɒn/) is a chemical element designated by the symbol Ar. Argon has atomic number 18 and is the third element in group 18 of the periodic table (noble gases).
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Electron

Theoretical estimates of the electron density for the first few hydrogen atom electron orbitals shown as cross-sections with color-coded probability density
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An electron shell, also known as a main energy level, is a group of atomic orbitals with the same value of the principal quantum number n. Electron shells are made up of one or more electron subshells, or sublevels
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In the physical sciences, a phase is a set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties (i.e. density, crystal structure, index of refraction, and so forth).
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Room temperature (also referred to as ambient temperature) is a common term to denote a certain temperature within enclosed space at which human beings are accustomed.
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In physics, density is mass m per unit volume V—how heavy something is compared to its size. A small, heavy object, such as a rock or a lump of lead, is denser than a lighter object of the same size or a larger object of the same weight, such as pieces of
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The melting point of a crystalline solid is the temperature range at which it changes state from solid to liquid. Although the phrase would suggest a specific temperature and is commonly and incorrectly used as such in most textbooks and literature, most crystalline compounds
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