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Copper compounds are used as bacteriostatic agents, fungicides, and wood preservatives. 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.
The chemical elements can be broadly divided into metals, metalloids, and nonmetals according to their shared physical and chemical properties.All elemental metals have a shiny appearance (at least when freshly polished); are good conductors of heat and electricity; form alloys with other metallic elements; and have at least one basic oxide.
The most reactive metals, such as sodium, will react with cold water to produce hydrogen and the metal hydroxide: 2 Na (s) + 2 H 2 O (l) →2 NaOH (aq) + H 2 (g) Metals in the middle of the reactivity series, such as iron , will react with acids such as sulfuric acid (but not water at normal temperatures) to give hydrogen and a metal salt ...
Silver, copper, and mercury are sometimes included as noble metals, but each of these usually occurs in nature combined with sulfur. In more specialized fields of study and applications the number of elements counted as noble metals can be smaller or larger.
Nonmetals show more variability in their properties than do metals. [1] Metalloids are included here since they behave predominately as chemically weak nonmetals.. Physically, they nearly all exist as diatomic or monatomic gases, or polyatomic solids having more substantial (open-packed) forms and relatively small atomic radii, unlike metals, which are nearly all solid and close-packed, and ...
The composition of fluxes is tailored for the required properties - the base metals and their surface preparation (which determine the composition and thickness of surface oxides), the solder (which determines the wetting properties and the soldering temperature), the corrosion resistance and ease of removal, and others.
Most pure metals are either too soft, brittle, or chemically reactive for practical use. Combining different ratios of metals and other elements in alloys modifies the properties to produce desirable characteristics, for instance more ductile, harder, resistant to corrosion, or have a more desirable color and luster.
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.