Copper
. Copper (element), symbol Cu, brownish-red metallic element that is one of the most widely used of metals. Copper is one of the transition elements of the periodic table (see Periodic Law ). The atomic number of copper is 29. Copper was known to prehistoric people and was probably the first metal from which useful articles were made. Copper objects have been found among the remains of many ancient civilizations, including those of Egypt, Asia Minor, China, southeastern Europe, Cyprus (from which the word copper is derived), and Crete (Kríti). It was known to Native Americans, and American ores were found by the European explorers. It is also found in the pure state. PROPERTIES AND USES Copper melts at about 1083° C (about 1981° F), boils at about 2567° C (about 4753° F), and has a specific gravity of 8.9. The atomic weight of copper is 63.546. Because of its many desirable properties, such as its conductivity of electricity and heat, its resistance to corrosion , its malleability and...