We explain what carbon is and what its main characteristics are. We also explain its applications and what the carbon cycle is.
What is carbon?
Carbon is one of the most important elements of the periodic table, at least in terms of its abundance and its necessity for organic life. More than 16 million carbon-containing substances are known, including many compounds essential for living beings. This element makes up 0.2% of the Earth’s crust.
carbon exists in numerous forms, depending on the environmental conditions in which it is found, and constitutes one of the elements with the most human uses and greatest presence in society. In fact, our body exhales carbon dioxide (CO2) as a product of respiration, and it is found as carbon monoxide (CO) in the gases released by the exhaust of combustion engines.
See also: Iron
Carbon characteristics
- Carbon in the periodic table is among the carbonoids, with atomic number 6, atomic mass 12.01 and is represented with the symbol C.
- It is a non-metallic element and is a good conductor of electricity when found in the form of graphite.
- Generally speaking, carbon is not a highly toxic substance. In most of its physical forms it is safe for human handling. However, many of the carbon-based organic and inorganic compounds can be toxic and even lethal to humans. Hydrocarbons, for example, can have a devastating effect on the respiratory system, just as much as coal (there are numerous cases of health deterioration in coal mine workers and workers at hydrocarbon exploitation stations).
- Carbon dioxide and carbon monoxide (CO2 and CO) are lethal substances if inhaled in large doses, as they prevent the body from properly oxygenating itself. The isotope carbon-14, being radioactive, represents a risk of contamination to some extent. Cyanide (CN-), one of the most lethal and popular poisons, is formed from carbon and nitrogen atoms.
- It is possible to find traces of carbon and hydrocarbons on distant planets, such as the gas giants of the Solar System, without this pointing to any type of organic life constitution, as far as we know.
Forms of carbon (halotropes)
Yes ok At room temperature carbon is solid, when it forms graphite it can sublimate when the temperature exceeds 3600 °C and turns into a gaseous state. In nature, however, it occurs in six different forms or allotropes (property of presenting different molecular or atomic structures):
- Amorphous carbon. Like soot or most coals, the pure element appears without a specific structure.
- GraphiteBlack, opaque and soft, graphite has the property of staining, which is why it is used as a filler for wooden pencils.
- Diamond. Diamond and graphite contain the same carbon atoms but in a different structure, so they also have different properties. The diamond is a transparent and extremely hard gemstone.
- Fulerenes. Discovered in the mid-80s, these are 60 carbon atoms structured no longer hexagonally, as usual, but heptagonally or pentagonally. This gives it a spherical appearance, like a soccer ball.
- Nanotubes. One of the first products of the nanotechnology industry, it is nothing more than sheets of graphite rolled cylindrically and topped at their ends by carbon hemispheres.
- Carbynes. One of the most powerful industrial products of recent decades, it consists of a carbon atom made univalent and electrically neutral, which is the most resistant substance ever known.
Chemical compounds with carbon
Carbon-based organic compounds
Many substances essential for life have carbon as their base. Fatty acids (made from combinations of carbon, oxygen and hydrogen), esters present in fruits, most amino acids, enzymes and proteins that sustain lifebenzene, carbohydrates that give us energy, all from combinations of carbon.
Carbon chemistry is known as the chemistry of life.since living beings known to date are based on molecular structures based on carbon. CO2 is essential for photosynthesis, for example.
Inorganic carbon-based compounds
In its extremely high combinative capacity, carbon is also found in numerous inorganic substances. Carbonates (calcites (CaCO3)), numerous salts and acids (carbonic acid (H2CO3))or metallic forms such as carbides and acetylides (calcium carbide (CaC2)), both of which are highly acidic, are forms of inorganic compounds made from carbon.
It may help you: Organic chemistry
Hydrocarbons
Hydrocarbons are substances composed of hydrogen and carbon atoms. These substances are linked to life (especially as fossil fuels), although they can exist on planets that have never hosted it. Oil and its derivatives, natural gases, methane, are hydrocarbons with very high industrial performance given their flammable nature.
More in: Hydrocarbons
carbon extraction
Since carbon is so abundant on our planet, It is usually abundant in underground regions where pressure and temperature allow it to rearrange itself in various structures. Thus, there are coal mines, but also graphite and diamond mines.
China, the United States and the European Union are the three largest coal exploiters on the planet, although It is abundantly distributed throughout 100 countries that extract it.On the other hand, fossil hydrocarbons, which are much more coveted, are found in large deposits in the Middle East, Russia, Alaska, Mexico and Venezuela, mainly.
Diamond exploitation is mainly concentrated in southern Africa and South America, although there are other smaller-scale mines in North America and South Asia. African exploitation has been very controversialdue to its human and political costs on the local population.
Industrial applications of carbon
Carbon extraction in its various forms is a common activity in the human economy, which mobilizes real masses around its extraction from the subsoil (coal, graphite and hydrocarbons) and their subsequent refining and use.
Hydrocarbons, above all, are an indispensable part of modern industrial machinery since they are high-performance fuels for all types of transportation thanks to the fact that Oil allows a wide range of usable derivatives like plastic or nylon. The same is true for the automotive lubricants industry.
Coal, on the other hand, is mainly used as a fuel to generate electricity, although its polluting effects are feared and proven. It is also used as a combustible material for domestic use.
Graphite is essential for the pencil industry and the protection rods of the atomic reactors. Diamonds, paradoxically, are valued as decorative objects or in the manufacture of scalpels and tools that take advantage of their hardness.
Finally, The radioactive isotope Carbon-14 is used in numerous scientific investigations and archaeological, as a marker of the age of organic remains.
Carbon cycle
The carbon cycle is known as feedback between plant, animal and decomposing organisms. Animal respiration and the decomposition of certain fungi release amounts of CO2 into the atmosphere.
This CO2 is used, along with water and sunlight, by the photosynthesis of plants, whose immediate product is oxygen and new organic matter (fruits, leaves, bark, dead animals) that then decomposes. And the cycle begins again, sustaining life as it spins.
Continue with: Polymers
References:
- “Carbon: the essentials” in WebElements.
- Organic Chemistry. John McMurry. CENGAGE Learning. ISBN 9706868232, 9789706868237
- “Carbon” in Wikipedia.