What is Copper?
Copper is a soft, reddish-brown, shiny metal that is a good conductor of heat and electricity. It is one of the most important metals in the metallurgical industry.
Copper is a metal widely used in the manufacture of cables, power lines, coins, keys, musical instruments (metals), mobile phones, jewelry, among others.
Also, copper is an important element as part of our diet. However, in high concentrations it can become toxic to humans and the environment. Foods that are high in copper include liver, walnuts, and vegetables, etc.
Copper in its natural state is in a solid state.
Chemical properties of copper
Below are the main chemical properties of copper.
- Chemical symbol: Cu.
- Atomic number: 29.
- Density: 8,960 kg / m 3.
- Atomic mass: 63.536 u.
- Oxidation states: +1, +2.
- Melting point: 1,357.77 Kelvin.
- Boiling point 3,200 Kelvin.
- Electrical conductivity 58,108 × 106 S / m.
- Thermal conductivity 400 W / (K · m).
Physical properties of copper
Below are the main physical properties of copper.
- It is a strong metal.
- It has high ductility (it is easily malleable).
- It is resistant to corrosion.
- It is a conductor of electricity.
- It is a conductor of heat.
- It has weldability.
- It has a low coefficient of thermal expansion.
Uses of copper and its derivatives
Due to the aforementioned properties, copper is a very versatile metal and has a wide variety of applications .
Below are different examples of the uses of pure copper and the three most common alloys: bronze , brass and cupronickel . However, it is important to mention that there are many other ways to combine this metal to give it other uses.
Manufacture of electrical cables
The copper used to make cables is protected by another external material in order to take care of its functionality.
Copper is widely used in the manufacture of cables due to its properties to conduct electricity, hence they are made with 99.90% pure copper.
Elaboration of statues
Bronze is used to make statues for its resistance and durability.
Bronze is an alloy that contains at least 60% copper and 40% tin. The addition of tin provides more hardness, prevents corrosion and changes its color, which is why it is used to make statues.
Bronze changes its color depending on the proportion of the metals that compose it. If the bronze tone is more golden, it has less copper. If instead it is more reddish, it has more copper.
Musical instrument making
The saxophone is an example of musical instruments made of brass.
Some wind musical instruments such as trumpets are made of brass. This alloy contains approximately 82% copper and 18% zinc, and is known for its hardness.
As in the previous example, the color of the alloy is an indicator of its copper content. If the metal is red, the zinc percentage is less than 18%, if it is gold-plated, the alloy has more zinc and less copper.
Elaboration of coins
Coins, like pennies on the dollar, are made of cupronickel.
The coins contain an alloy of copper and nickel, called cupronickel. The proportions commonly used for are:
- 90% copper and 10% nickel.
- 70% copper and 30% nickel.
Cupronickel is highly resistant to corrosion, which is why it is also commonly used in the pipes of desalination plants and in aquaculture cages.
Chemical compounds with atomic copper
Atomic copper can be found in combination with other elements such as oxygen (O), sulfur (S) or chlorine (Cl). Examples of these chemical compounds and their most common uses are listed below.
- The cupric sulfate [CuSO 4 ] is a salt commonly used in the agricultural industry as fertilizer and pesticide.
- The cuprous oxide [Cu 2 O] is used as a fungicide.
- Mixtures containing cupric oxide [CuO] between 2 and 10% give ceramic tiles a metallic luster and shades ranging from turquoise green to deep black.
- The copper chloride [CuCl 2 ] is used in the oil industry as a catalyst to remove corrosive material called mercaptan.
- The copper acetate [OCU 2 (OAc) 4 (H 2 O) 2 ] is used as a catalyst in the chemical industry.
The importance of copper in human physiology
Copper is a very important metal for the functioning of the human body, even though the amounts ingested seem small, these are enough to generate connective tissue and bone marrow cells such as red blood cells or cells of the immune system.
The amounts of copper that the body requires are small, however, these are enough to generate connective tissue, red blood cells or macrophages.
That is, it must be ingested through various foods in order for it to be available in our body. The ideal and recommended is to consume 900 micrograms of copper daily.
Main foods with copper
The foods in the daily diet that contain copper are mentioned below.
- Liver:67 grams provides 1,144% of the daily requirement
- Oysters:100 grams provide 844% of the daily requirement.
- Spirulina: 7 grams contributes 11% of the daily requirement.
- Shiitake Mushrooms : 15 grams provide 89% of the daily requirement.
- Nuts and seeds: 28 grams of cashews provide 33% of the daily requirement.
- Lobster: 85 grams of lobster provide 178% of the daily requirement.
- Green vegetables: 180 grams of cooked spinach provides 33% of the daily requirement.
- Dark Chocolate: 100 grams of chocolate with 75% cocoa contains 67% of the daily requirement.