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Spectral lines of copper: Other properties; ... Copper is a chemical element. ... A table of the old and new adult daily values is provided at Reference Daily Intake.
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 ...
Copper alloys are metal alloys that have copper as their principal component. They have high resistance against corrosion . Of the large number of different types, the best known traditional types are bronze , where tin is a significant addition, and brass , using zinc instead.
Group 11, by modern IUPAC numbering, [1] is a group of chemical elements in the periodic table, consisting of copper (Cu), silver (Ag), gold (Au), and roentgenium (Rg), although no chemical experiments have yet been carried out to confirm that roentgenium behaves like the heavier homologue to gold.
The method of producing OFHC copper ensures an extra high grade of metal with a copper content of 99.99%. With so small a content of extraneous elements, the inherent properties of elemental copper are brought forth to a high degree. In practice the oxygen content is typically 0.001 to 0.003% with a total maximum impurity level of 0.03%.
The first periodic table to become generally accepted was that of the Russian chemist Dmitri Mendeleev in 1869; he formulated the periodic law as a dependence of chemical properties on atomic mass. As not all elements were then known, there were gaps in his periodic table, and Mendeleev successfully used the periodic law to predict some ...
Islamic Golden Age brass astrolabe Brass lectern with an eagle. Attributed to Aert van Tricht, Limburg (Netherlands), c. 1500.. Brass is an alloy of copper and zinc, in proportions which can be varied to achieve different colours and mechanical, electrical, acoustic and chemical properties, [1] but copper typically has the larger proportion, generally 2 ⁄ 3 copper and 1 ⁄ 3 zinc.
Bronze is an alloy consisting primarily of copper, commonly with about 12–12.5% tin and often with the addition of other metals (including aluminium, manganese, nickel, or zinc) and sometimes non-metals (such as phosphorus) or metalloids (such as arsenic or silicon).