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Copper fittings for soldered plumbing joints A very large copper seal end cap. 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). [28]
Example of a copper alloy object: a Neo-Sumerian foundation figure of Gudea, circa 2100 BC, made in the lost-wax cast method, overall: 17.5 x 4.5 x 7.3 cm, probably from modern-day Iraq, now in the Cleveland Museum of Art (Cleveland, Ohio, USA) Copper alloys are metal alloys that have copper as their principal component.
Copper(II) oxide or cupric oxide is an inorganic compound with the formula CuO. A black solid, it is one of the two stable oxides of copper, the other being Cu 2 O or copper(I) oxide (cuprous oxide). As a mineral, it is known as tenorite, or sometimes black copper.
Copper occurs in its native form in Chile, China, Mexico, Russia and the USA. Various natural ores of copper are: copper pyrites (CuFeS 2), cuprite or ruby copper (Cu 2 O), copper glance (Cu 2 S), malachite (Cu(OH) 2 CuCO 3), and azurite (Cu(OH) 2 2CuCO 3). Copper pyrite is the principal ore, and yields nearly 76% of the world production of copper.
Copper(I) oxide or cuprous oxide is the inorganic compound with the formula Cu 2 O. It is one of the principal oxides of copper , the other being copper(II) oxide or cupric oxide (CuO).The compound can appear either yellow or red, depending on the size of the particles. [ 2 ]
Copper's higher tensile strength (200–250 N/mm 2 annealed) compared to aluminium (100 N/mm 2 for typical conductor alloys [16]) is another reason why copper is used extensively in the building industry. Copper's high strength resists stretching, neck-down, creep, nicks and breaks, and thereby also prevents failures and service interruptions. [17]
Copper (29 Cu) has two stable isotopes, 63 Cu and 65 Cu, along with 28 radioisotopes. The most stable radioisotope is 67 Cu with a half-life of 61.83 hours. Most of the others have half-lives under a minute. Unstable copper isotopes with atomic masses below 63 tend to undergo β + decay, while isotopes with atomic masses above 65 tend to ...
Native copper is an uncombined form of copper that occurs as a natural mineral. Copper is one of the few metallic elements to occur in native form, although it most commonly occurs in oxidized states and mixed with other elements. Native copper was an important ore of copper in historic times and was used by pre-historic peoples.