Copper

Characteristics and Properties of Copper

• Copper is a soft, malleable, and ductile metal.
• It has high thermal and electrical conductivity.
• Copper has a pinkish-orange color when freshly exposed.
• It is used as a conductor of heat and electricity.
• Copper is a constituent of various metal alloys.
• Copper has a red-orange metallic luster.
• Its standard atomic weight is 63.546±0.003.
• The boiling point of copper is 2835K (2562°C, 4643°F).
• The density of copper is 8.96g/cm³ (near room temperature).
• Copper has a thermal expansion of 16.5µm/(m⋅K) (at 25°C).
• Copper does not react with water but slowly reacts with atmospheric oxygen to form a protective layer of copper oxide.
• It can tarnish when exposed to sulfur compounds, forming copper sulfides.
• Copper compounds are used as pigments, bacteriostatic agents, fungicides, and wood preservatives.
• Copper is essential to all living organisms as a trace dietary mineral.
• In humans, copper is mainly found in the liver, muscle, and bone.

Isotopes and Occurrence of Copper

• Copper has 29 isotopes, with two stable isotopes, Cu-63 and Cu-65.
• Cu-63 and Cu-65 make up approximately 69% of naturally occurring copper.
• Copper isotopes with a mass number above 64 decay by beta decay.
• Cu-64 has a half-life of 12.7 hours and decays both ways.
• Some copper isotopes have significant applications, such as Cu-64 used in positron emission tomography.
• Copper is present in the Earth's crust in a proportion of about 50 parts per million (ppm).
• It occurs in a variety of minerals, including native copper, copper sulfides, copper sulfosalts, copper carbonates, and copper oxides.
• The largest mass of elemental copper discovered weighed 420 tonnes.
• Native copper is a polycrystal, and the largest single crystal measured 4.4 × [missing information].
• Copper is produced in massive stars.

Production, Reserves, and Recycling of Copper

• Chuquicamata in Chile is one of the world's largest open pit copper mines.
• Copper production is dominated by large open pit mines in porphyry copper deposits.
• Top copper producers in 2005 were Chile, United States, Indonesia, and Peru.
• In-situ leach process is an alternative method for copper recovery.
• Polymetallic nodules in the Pacific Ocean are being researched as a potential source of copper.
• Over 95% of all copper ever mined and smelted has been extracted since 1900.
• The total amount of copper on Earth is vast, but only a small fraction is economically viable.
• Estimates of copper reserves available for mining vary from 25 to 60 years.
• Recycling is a major source of copper in the modern world.
• Copper prices are volatile and can experience unexpected fluctuations.
• The majority of copper ores are sulfides, such as chalcopyrite and bornite.
• Ore concentration is achieved through comminution and froth flotation.
• Smelting and electrolysis are used to purify copper.
• Oxide ores are also processed through sulfuric acid extraction and electrolysis.
• Recycling involves melting and refining copper.
• Copper is highly recyclable without any loss of quality.
• Copper is the third most recycled metal after iron and aluminum.
• An estimated 80% of all copper ever mined is still in use today.
• The process of recycling copper is similar to extracting copper but requires fewer steps.
• High-purity scrap copper is melted and cast into billets and ingots.

Environmental Impacts of Copper Mining

• Copper mining has an estimated environmental cost of 3.7 kg CO2eq per kg of copper.
• Greenhouse gas emissions primarily come from electricity consumption and extraction/refinement processes.
• Improper waste management by mining companies can render land sterile and negatively impact nearby rivers and forests.
• Copper mining waste can significantly alter water properties, making it inhospitable for aquatic life.
• Examples of environmental impacts include the Philippines and Valea Şesei in Romania.

Alloys, Compounds, and History of Copper

• Numerous copper alloys have been formulated, including brass and bronze.
• Copper is an important constituent of silver and karat gold solders used in the jewelry industry.
• Some lead-free solders consist of copper alloyed with tin and other metals.
• Cupronickel is an alloy of copper and nickel used in low-denomination coins.
• Copper alloys with aluminum have a golden color and are used in decorations.
• Copper forms a rich variety of compounds with oxidation states +1 and +2.
• These compounds are often called cuprous and cupric, respectively.
• Copper compounds promote or catalyze numerous chemical and biological processes.
• Important examples of copper compounds include copper(I) sulfide and copper monosulfide.
• Cuprous and cupric halides with fluorine, chlorine, bromine, and iodine are known.
• The simplest compounds of copper are binary compounds containing only two elements.
• Examples of binary compounds include oxides, sulfides, and halides.
• Both cuprous and cupric oxides are known.
• Copper(I) sulfide (CuS) and copper monosulfide (CuS) are important copper sulfides.
• Cuprous and cupric halides with fluorine, chlorine, bromine, and iodine are known.
• Copper(II) gives a deep blue coloration in the presence of ammonia ligands.
• Copper forms coordination complexes with ligands.
• In aqueous solution, copper(II) exists as [Cu(H2O)6]2+.
• Adding aqueous sodium hydroxide causes the precipitation of light blue solid copper(II)

Copper Data Sources