![]() ![]() īy 2000 BC, Europe was using copper-tin alloys or bronze. 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. 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 one pyramid, a copper plumbing system was found that is 5000 years old. 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. High levels of arsenic in his hair suggest he was involved in copper smelting. 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. Copper is found extensively in the Indus Valley Civilization by the 3rd millennium BC. 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. #COPPER POURBAIX DIAGRAM SKIN#But Can Hasan (~5000 BC) had access to smelted copper this site has yielded the oldest known cast copper artifact, a copper mace head.Īncient Copper ingot from Zakros, Crete is shaped in the form of an animal skin typical for that era.Ĭopper smelting appears to have been developed independently in several parts of the world. Among archaeological sites in Anatolia, Çatal Höyük (~6000 BC) features native copper artifacts and smelted lead beads, but no smelted copper. By 5000 BC, there are signs of copper smelting, the refining of copper from simple copper compounds such as malachite or azurite. A copper pendant was found in what is now northern Iraq that dates to 8700 BC. 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. High demand relative to supply has caused a price spike in the 2000s.Ĭopper, as native copper, is one of the few metals to naturally occur as an uncompounded mineral. 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. 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. Civilizations in places such as Iraq, China, Egypt, Greece, India and the Sumerian cities all have early evidence of using copper. However, in sufficient amounts, copper can be poisonous and even fatal to organisms.Ĭopper has played a significant part in the history of mankind, which has used the easily accessible uncompounded metal for thousands of years. In animals, including humans, it is found primarily in the bloodstream, as a co-factor in various enzymes, and in copper-based pigments. 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.Ĭopper is an essential trace nutrient to all high plants and animals. The "H" stands for hydrogen, although other standards may be used, and they are for room temperature only.Copper ( Template:PronEng) is a chemical element with the symbol Cu ( Template:Lang-la) and atomic number 29. The vertical axis is labeled E H for the voltage potential with respect to the standard hydrogen electrode (SHE) as calculated by the Nernst equation. Pourbaix diagrams are also known as E H-pH diagrams due to the labeling of the two axes. The Pourbaix diagram for uranium in a non-complexing aqueous medium (e.g. The diagrams are named after Marcel Pourbaix (1904–1998), the Russian-born Belgian chemist who invented them. Pourbaix diagrams are commonly given at room temperature, atmospheric pressure, and molar concentrations of 10 −6 and changing any of these parameters will yield a different diagram. Beside potential and pH, the equilibrium concentrations are also dependent upon, e.g., temperature, pressure, and concentration. Similarly to phase diagrams, they do not allow for reaction rate or kinetic effects. As such a Pourbaix diagram can be read much like a standard phase diagram with a different set of axes. Boundaries (50 %/50 %) between the predominant chemical species (aqueous ions in solution, or solid phases) are represented by lines. In electrochemistry, and more generally in solution chemistry, a Pourbaix diagram, also known as a potential/pH diagram, E H–pH diagram or a pE/pH diagram, is a plot of possible thermodynamically stable phases ( i.e., at chemical equilibrium) of an aqueous electrochemical system. The Y axis corresponds to voltage potential. ![]()
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