Copper (Cuprum) is a metal element, but also a transition element, chemical symbol Cu, English copper, atomic number 29. pure copper is a soft metal, the surface just cut for the reddish-orange with a metallic luster, the monomers are purplish-red.
Good ductility, thermal conductivity and high electrical conductivity, so in the cable and electrical and electronic components is the most commonly used materials, can also be used as building materials, can be composed of numerous kinds of alloys. Copper alloys have excellent mechanical properties and low electrical resistivity, the most important of which are bronze and brass. In addition, copper is a durable metal and can be recycled many times without loss of mechanical properties.
Divalent copper salts are the most common copper compounds; their hydrated ions often appear blue, while chlorine as a ligand appears green, and is the source of the color of minerals such as blue chalcopyrite and turquoise, which have been widely used as pigments throughout history. Copper architectural structures are corroded to produce a copper green (basic copper carbonate). The decorative arts primarily use metallic copper and copper-containing pigments.
Copper was one of the first metals used by humans. As early as prehistoric times, people began mining open-pit copper mines and using the copper they obtained to make weapons, tools, and other utensils, and the use of copper had a profound impact on the progress of early human civilization. Copper is a metal found in the earth’s crust and in the oceans. The content of copper in the earth’s crust is about 0.01%, and in individual copper deposits, the content of copper can reach 3% to 5%. Most of the copper in nature exists as compounds, i.e. copper ores.
The activity of copper is weak, iron monomers and copper sulfate reaction can replace the copper monomers. Copper monomers are insoluble in non-oxidizing acids.
Copper density of 8-9g/cm3; melting point 1083 ° C. Pure copper conductivity is very good, a large number of wires, cables, brushes, etc.; good thermal conductivity, commonly used in the manufacture of anti-magnetic interference with magnetic instruments, instruments, such as compasses, aviation instrumentation, etc.; plasticity is very good, easy to hot and cold pressure processing can be made into a tube, rod, wire, strip, strip, plate, foil and other copper materials. Pure copper products are smelted and processed products.