Copper (Cu) is a reddish, very ductile metal that belongs to Group 11 of the periodic table. It is a particularly good conductor of electricity and heat. Copper is found in nature in its free metallic state.
Neolithic (New Stone Age) humans initially utilized this natural copper as a stone replacement around 8000 BCE. Metallurgy began in Mesopotamia with the casting of copper into moulds (c. 4000 BCE). The reduction of ores to metal using fire and charcoal, and the purposeful alloying of copper with tin as bronze (c. 3500 BCE). Copper was nearly totally supplied by Cyprus to the Romans. Aes Cyprium, or "metal of Cyprus," was the name given to it. It was abbreviated to cyprium and later corrupted to cuprum.
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Occurrence of copper
- Copper is found as the main mineral in basaltic lavas and as a reduced form of copper compounds such as sulphides, chlorides, arsenides, and carbonates in many places.
- Copper can be found in chalcopyrite, chalcocite, bornite, malachite, cuprite, and azurite, among other minerals.
- It's found in seaweed ashes, numerous marine corals, a human liver, and various arthropods and mollusks.
- The world's largest known copper deposit is a porphyry copper deposit in Chile's Andes Mountains.
- Chile has become the world's biggest copper producer by the early twenty-first century. Peru, the United States, and China are among the other main producers.
Uses of copper
- Copper has an important role in oxygen transport in mollusks (blue-blooded) and crustacean’s hemocyanin as iron does in red-blooded species haemoglobin.
- Copper, found in trace amounts in humans, aids in the catalysis of haemoglobin synthesis.
Production and uses of copper
- Copper is commercially produced primarily through smelting or leaching, with electrodeposition from sulphate solutions commonly following.
- The electrical industries consume the majority of copper produced worldwide; the remainder is mixed with other metals to generate alloys.
- It's also crucial in terms of technology as an electroplated coating.)
- Brasses (zinc and copper), bronzes (tin and copper), and nickel silvers are all important series of alloys. Copper is a major component (zinc, copper and nickel).
- Nickel and Copper alloys, such as Monel, are extremely valuable since the two metals are fully miscible.
- Aluminum bronzes are a popular series of alloys that combine copper and aluminium.
- Beryllium copper (Be 2 percent) is a unique copper alloy because it can be heat hardened. Copper is found in a variety of coinage metals.
- Copper remained the second most important metal in importance to iron even after the Bronze Age moved into the Iron Age.
Properties of copper
- Copper is a ductile metal that isn't particularly hard or strong.
- Because of the production of elongated crystals of cubic structure (face-centered) found in the softer annealed copper, cold-working increases hardness and strength significantly.
- Common gases such as oxygen, nitrogen, carbon dioxide, and sulphur dioxide are soluble in molten copper. They have a significant impact on the solidified metal's electrical and mechanical properties.
- In terms of electrical and thermal conductivity, the pure metal is only second to silver.
- Copper is made up of two stable isotopes: copper-65 (65.15 percent) and copper-63 (69.15 percent).
- Copper is not soluble in acids that evolve hydrogen because it is below hydrogen in the electromotive series. Still it will react with oxidising acids like nitric and hot, concentrated sulfuric acid.
- Copper is resistant to the effects of the environment and seawater.
- On the contrary, long-term air exposure results in the production of a thin green protective coating (patina) made up of hydroxosulfate, hydroxocarbonate, and a few other chemicals.
- Copper is a relatively noble metal in the absence of air. It is unaffected by non-complexing or non-oxidizing dilute acids. In the presence of oxygen, it will dissolve rapidly in sulfuric acid and nitric acid.
- Because of the generation of relatively stable cyano complexes upon dissolution, it is also soluble in potassium cyanide or aqueous ammonia in the presence of oxygen.
- At red heat, the metal reacts with oxygen to form a cupric oxide, CuO, and cuprous oxide, and Cu2O, at higher temperatures.
- When heated with sulphur, it forms cuprous sulphide(Cu2S).