Carbon fibre is finding many uses as a very strong, yet lightweight, material. It is currently used in tennis rackets, skis, fishing rods, rockets and aeroplanes. Industrial diamonds are used for cutting rocks and drilling. Diamond films are used to protect surfaces such as razor blades. The more recent discovery of carbon nanotubes, other fullerenes and atom-thin sheets of graphene has revolutionised hardware developments in the electronics industry and in nanotechnology generally.
In , as a result of combusting fossil fuels with oxygen, there was ppm. Atmospheric carbon dioxide allows visible light in but prevents some infrared escaping the natural greenhouse effect.
This keeps the Earth warm enough to sustain life. However, an enhanced greenhouse effect is underway, due to a human-induced rise in atmospheric carbon dioxide. This is affecting living things as our climate changes. Biological role. Carbon is essential to life. This is because it is able to form a huge variety of chains of different lengths.
It was once thought that the carbon-based molecules of life could only be obtained from living things. However, in , urea was synthesised from inorganic reagents and the branches of organic and inorganic chemistry were united. Living things get almost all their carbon from carbon dioxide, either from the atmosphere or dissolved in water. Photosynthesis by green plants and photosynthetic plankton uses energy from the sun to split water into oxygen and hydrogen.
The oxygen is released to the atmosphere, fresh water and seas, and the hydrogen joins with carbon dioxide to produce carbohydrates. Some of the carbohydrates are used, along with nitrogen, phosphorus and other elements, to form the other monomer molecules of life. Living things that do not photosynthesise have to rely on consuming other living things for their source of carbon molecules. Their digestive systems break carbohydrates into monomers that they can use to build their own cellular structures.
Respiration provides the energy needed for these reactions. In respiration oxygen rejoins carbohydrates, to form carbon dioxide and water again. The energy released in this reaction is made available for the cells. Natural abundance. Carbon is found in the sun and other stars, formed from the debris of a previous supernova. It is built up by nuclear fusion in bigger stars. It is present in the atmospheres of many planets, usually as carbon dioxide. On Earth, the concentration of carbon dioxide in the atmosphere is currently ppm and rising.
Graphite is found naturally in many locations. Diamond is found in the form of microscopic crystals in some meteorites. In combination, carbon is found in all living things.
It is also found in fossilised remains in the form of hydrocarbons natural gas, crude oil, oil shales, coal etc and carbonates chalk, limestone, dolomite etc. Help text not available for this section currently. Elements and Periodic Table History. Carbon occurs naturally as anthracite a type of coal , graphite, and diamond.
More readily available historically was soot or charcoal. Ultimately these various materials were recognised as forms of the same element. Not surprisingly, diamond posed the greatest difficulty of identification. Naturalist Giuseppe Averani and medic Cipriano Targioni of Florence were the first to discover that diamonds could be destroyed by heating. In they focussed sunlight on to a diamond using a large magnifying glass and the gem eventually disappeared. Pierre-Joseph Macquer and Godefroy de Villetaneuse repeated the experiment in Then, in , the English chemist Smithson Tennant finally proved that diamond was just a form of carbon by showing that as it burned it formed only CO 2.
Atomic data. Bond enthalpies. Glossary Common oxidation states The oxidation state of an atom is a measure of the degree of oxidation of an atom. Oxidation states and isotopes. Glossary Data for this section been provided by the British Geological Survey. Relative supply risk An integrated supply risk index from 1 very low risk to 10 very high risk. Recycling rate The percentage of a commodity which is recycled.
Substitutability The availability of suitable substitutes for a given commodity. Reserve distribution The percentage of the world reserves located in the country with the largest reserves. Political stability of top producer A percentile rank for the political stability of the top producing country, derived from World Bank governance indicators.
Political stability of top reserve holder A percentile rank for the political stability of the country with the largest reserves, derived from World Bank governance indicators. Supply risk. Coal Diamond Graphite Coal. Relative supply risk 4. Relative supply risk 6.
Relative supply risk 8. Young's modulus A measure of the stiffness of a substance. Shear modulus A measure of how difficult it is to deform a material. Bulk modulus A measure of how difficult it is to compress a substance. Vapour pressure A measure of the propensity of a substance to evaporate. Pressure and temperature data — advanced. Listen to Carbon Podcast Transcript :. You're listening to Chemistry in its element brought to you by Chemistry World , the magazine of the Royal Society of Chemistry.
Hello, this week to the element that unites weddings, wars, conflicts and cremations and to explain how, here's Katherine Holt. Any chemist could talk for days about carbon. It is after all an everyday, run-of-the-mill, found-in-pretty-much-everything, ubiquitous element for us carbon-based life forms. An entire branch of chemistry is devoted to its reactions. In its elemental form it throws up some surprises in the contrasting and fascinating forms of its allotropes.
It seems that every few years a new form of carbon comes into fashion - A few years ago carbon nanotubes were the new black or should I say 'the new bucky-ball' - but graphene is oh-so-now! But today I'm going to talk about the most glamorous form that carbon can take - diamond. For millennia diamond has been associated with wealth and riches, as it can be cut to form gemstones of high clarity, brilliance and permanence.
Diamonds truly are forever! Unfortunately, diamond also has a dark side - the greed that diamond induces leads to the trade of so-called 'conflict diamonds' that support and fund civil wars.
Mans desire for diamond has led alchemists and chemists over many centuries to attempt to synthesise the material. After many fraudulous early claims diamond was finally synthesised artificially in the s.
Scientists took their inspiration from nature by noting the conditions under which diamond is formed naturally, deep under the earth's crust. This was an impressive feat, but the extreme conditions required made it prohibitively expensive as a commercial process.
Since then the process has been refined and the use of metal catalysts means that lower temperatures and pressures are required. Crystals of a few micron diameter can be formed in a few minutes, but a 2-carat gem quality crystal may takes several weeks. These techniques mean its now possible to artificially synthesise gemstone quality diamonds which, without the help of specialist equipment, cannot be distinguished from natural diamond.
It goes without saying that this could cause headaches among the companies that trade in natural diamond! It is possible to turn any carbon based material into a diamond - including hair and even cremating remains! Yes - you can turn your dearly departed pet into a diamond to keep forever if you want to! Artificial diamonds are chemically and physical identical to the natural stones and come without the ethical baggage. However, psychologically their remains a barrier - if he really loves you he'd buy you real diamond - wouldn't he?
From the perspective of a chemist, materials scientist or engineer we soon run out of superlatives while describing the amazing physical, electronic and chemical properties of diamond. It is the hardest material known to man and more or less inert - able to withstand the strongest and most corrosive of acids.
It has the highest thermal conductivity of any material, so is excellent at dissipating heat. That is why diamonds are always cold to the touch.
Having a wide band gap, it is the text book example of an insulating material and for the same reason has amazing transparency and optical properties over the widest range of wavelengths of any solid material. You can see then why diamond is exciting to scientists. Its hardness and inert nature suggest applications as protective coatings against abrasion, chemical corrosion and radiation damage.
The research team named their discovery the buckminsterfullerene after an architect who designed geodesic domes. The molecule is now more commonly known as the "buckyball. Buckyballs have been found to inhibit the spread of HIV, according to a study published in in the Journal of Chemical Information and Modeling ; medical researchers are working to attach drugs, molecule-by-molecule, to buckyballs in order to deliver medicine directly to sites of infection or tumors in the body; this includes research by Columbia University , Rice University and others.
Since then, other new, pure carbon molecules — called fullerenes — have been discovered, including elliptical-shaped "buckyeggs" and carbon nanotubes with amazing conductive properties. Carbon chemistry is still hot enough to capture Nobel Prizes: In , researchers from Japan and the United States won one for figuring out how to link carbon atoms together using palladium atoms, a method that enables the manufacture of large, complex carbon molecules, according to the Nobel Foundation.
Scientists and engineers are working with these carbon nanomaterials to build materials straight out of science-fiction. A paper in the journal Nano Letters reports the invention of flexible, conductive textiles dipped in a carbon nanotube "ink" that could be used to store energy, perhaps paving the way for wearable batteries, solar cells and other electronics.
Perhaps one of the hottest areas in carbon research today, however, involves the "miracle material" graphene. Graphene is a sheet of carbon only one atom thick. It's the strongest material known while still being ultralight and flexible. And it conducts electricity better than copper. Mass-producing graphene is a challenge, though researchers in April reported that they could make large amounts using nothing but a kitchen blender.
If scientists can figure out how to make lots of graphene easily, the material could become huge in tech. Imagine flexible, unbreakable gadgets that also happen to be paper-thin. Carbon has come a long way from charcoal and diamonds, indeed. A carbon nanotube CNT is a minuscule, straw-like structure made of carbon atoms. These tubes are extremely useful in a wide variety of electronic, magnetic and mechanical technologies.
The diameters of these tubes are so tiny that they are measured in nanometers. A nanometer is one-billionth of a meter — about 10, times smaller than a human hair. Carbon nanotubes are at least times stronger than steel, but only one-sixth as heavy, so they can add strength to almost any material, according to nanoScience Instruments.
They are also better than copper at conducting electricity and heat. Nanotechnology is being applied to the quest to turn seawater into drinking water. In a new study, scientists at Lawrence Livermore National Laboratory LLNL have developed a carbon nanotube process that can take the salt out of seawater far more efficiently than traditional technologies. For example, traditional desalination processes pump in seawater under high pressure, sending it through reverse osmosis membranes.
Graphite may be considered as the highest grade of coal above anthracite and therefore is found in small quantities wherever coal is found. It was used pretty much throughout history as "black paint", it seems, e. Personally, I'm not sure if the graphite paint found on old pottery resulted from using "true" graphite or just soot.
After firing the pots, the result could be about the same. Graphite proper came into its own after a huge deposit of extremely pure and soft stuff was discovered in or possibly somewhat earlier in the Borrowdale parish, Cumbria, England. The local yokels used it for marking sheep and probably didn't worry much about what that soft black stuff actually could be.
A somewhat more advanced use coming up a bit later was to line the molds for cannon balls with this graphite, resulting in rounder, smoother balls that could be fired farther. The military guys did wonder about what that useful black stuff could be, and promptly confused it with lead or some of the more common lead ores like galena.
That is why graphite was known for a long time as "lead" or " plumbago " based on the Latin "plumbum" for lead. This error survived to some extent up to the present day. In German, a pencil is still called "Bleistift", literally "lead pen". Archeologists also confused lead and lead ore. Granted that graphite, lead and galena look similar, one could at least distinguish graphite from the two others easily because the difference in specific weight is rather obvious, you might think.
Yes, but to everybody before - roughly - , the notion of chemical elements was unknow. Things that were similar were thought to be about the same. The differences were assigned to the presence or absence of "vital juices", "spirits" or "priciples" of this or that. Graphite in many aspects is far more similar to lead or lead ore then to diamond, or soot. I'm quite sure that even today it would be far easier to persuade most people that graphite is related to lead and not to diamond. Soot and Carbon Black.
Soot is that fine black stuff that remains in the air from burning something, and that the chimney sweep takes out of your chimney on a regular base. You only can avoid it in very "clean" fires. It results from the "incomplete combustion of a hydrocarbon", for example when a candle burns wax. Put a glass plate over a candle flame and you catch the soot in the air. It is part of what we call "smoke" and accounts for a lot of sick people, especially in countries where open fires are the standard for cooking.
Soot consists of rather small below nm particles of carbon plus some dirt. This particles might agglomerate to some extent, forming chains and God knows what, and at least parts of them consist of amorphous carbon. I'm sure, however, that you will find all other forms of carbon too, if you search long enough. Atomic structure of graphitized carbon black; HRTEM picture The parallel lines are small graphite nano crystals; you look at the hexagonal planes "edge-on".
Source: Obscure old Russian text book from A. Kitaigorodsky; actual source not identified. Soot, made unintentionally by you via burning something, should not be confused with carbon black that is made intentionally by burning something. Carbon black is rather pure carbon that serves as raw material for important carbon-based products. It is, for example, used as pigment in your toner cartridge, and it is what makes care tires black.
World production is around 10 Mio. Make it very hot and it graphitizes as shown above. And don't confuse "carbon black" with Black Carbon - look it up yourself! Ancient man used soot for painting himself, for tattooing, painting caves, whatever. It was not High-Tech and thus is not very interesting to us. Modern man like me and my colleagues used very pure carbon black for a while in experiments designed to make very pure silicon via " electro-smelting of difficult elements ".
That also needed very clean silicon dioxide SiO 2. It didn't really work but that is another story. Working with the stuff makes everything including you quite black, too.
I have never done anything quite that dirty again during my career, and that includes convincing my kids that the shortcuts I proposed on major hikes would bring us home pronto, not to mention running a major university faculty as Dean. History of Putting Things Together. You must admit that anybody not familiar with the basics of chemistry and the periodic table would declare you to be completely nuts if you would propose that all the stuff described above is one and the same basic substance.
Before about , "anybody not familiar" and so on would simply have been everybody minus a handful of fledgling scientists. It was Robert Boyle who suspected in that there were more than just the four classical elements that the ancients had postulated.
He endorsed the view of elements as the undecomposable constituents of material bodies and made a distinction between mixtures and compounds. Nevertheless, he was also an alchemist and a racist and believed in the transmutation of metals - making gold from lead, in other words. Oxygen, nitrogen, hydrogen, phosphorus, mercury, zinc, and sulfur were correctly identified as elements - but also light and " caloric " heat stuff , which he incorrectly believed to be a material substance.
In he also recognized soot as being the element carbon, and more importantly, established that diamond was also carbon by doing the amazing experiment described below. While Lavoisier's work was daring and pioneering, we need to be aware that Lavoisier could not really prove beyond any doubt if some substance was an element or a compound.
His inclusion of carbon, while correct, could also be seen as a lucky guess. It was not clear, for example, which manifestations of the element were really carbon. Some experiment by one Guyton de Morveau much later in lead others to believe that only diamond would be pure carbon, while graphite would be an oxide of the "1st degree", charcoal of the 2nd degree, and carbonic acid, finally, would be the "complete oxide". Pepys and Allen corrected that in , which helped Dalton in formulating his "law of multiple proportions" in , paving the road to atoms and the periodic table.
Of course, Lavoisier was neither alone in his enterprise nor did everybody believe him right away or later, considering that there are mistakes; see below. The eminent Priestley , for example, also credited with "discovering" oxygen, never believed him at all. It goes wothout saying that the people actually making and working with iron and steel couldn't have cared less for quite a while. Major insights were fine around then but usually not all that helpful for practitioners.
Source: Wertheim's book. Obviously from an early translation to English. Some time in , Lavoisiser and some of his buddies pooled their funds, purchased a diamond, put it into a closed glass jar, and focussed the rays of the sun on it with a big lens, supplying the ultimate "clean" heat. The diamond disappeared and since the weight of the glass jar was unchanged, the unavoidable conclusion was that the diamond had turned into a gas that could only be carbon dioxide, proving that a diamond was pure carbon.
The experiment was not as simple it as it appears nowadays, as this contemporary illustration proves:. I don't know how Lavoisier's insight was received by the public but will bet that almost nobody believed him and that his wife was mad at him for destroying that diamond.
Well, Lavoisier also supported the metric system , and fought for the rights of a number of foreign-born scientists, including mathematician Joseph Louis Lagrange , during the Reign of Terror, so he had it coming for himself. In essence, the 18th century was when "chemistry" was born. This was a difficult delivery because it required not only to do away with the "four element theory" plus "aether" or "quintessence", added by Aristotle, being wrong as ususal , as the fifth element but also to get rid of the more modern " phlogiston " theory.
Boyle and Lavoisier, mentioned above, were decisive in this enterprise, but also a lot of other fledgling scientists. Carl Wilhelm Scheele noticed in , four year after Lavosisier recognized soot to be carbon, that graphite was carbon, too. Of course now you wonder. Just above I wrote that Lavoisier had oxygen, nitrogen and so on listed as elements - and that was earlier. Well, as far as oxygen is concerned, I must also mention Joseph Priestley who described a special gas - we call it oxygen - in , even before Lavosisier.
I guess the discovery of oxygen and nitrogen was in the air, so to speak. As far as priorities go, Scheele probably made his discoveries in , even before Priestley, but published it later than Lavoisier. Whatever, Priestley and Lavosier were English and French and thus not trustworthy; look what they did with Lavoisier.
Scheele was German and now you could believe it. Scheele won ever-lasting fame by being instrumental in overturning the phlogiston theory. Smithson Tennant , an English chemist, not only discovered the elements iridium Ir and osmium Os but proved in once more, but now also beyond reasonable doubt for the imbecile, lawyers and politicians, that diamond is indeed a phase of carbon. So at the beginning of the 19th century it was clear that soot, graphite, diamond, coal, coke and charcoal were just different manifestations of the element carbon, containing more or less "dirt" on the side.
In the following years the understanding of carbon manifestations was refined and developed in great detail but nothing really new was added to the list above until about when small diamonds could be synthesized to some extent. Somewhat later, around , the new and exciting carbon manifestations known under names like "Bucky balls", fullerenes, carbon nanotubes and graphene, started to appear, causing major scientific orgasms. The party is still on.
This is described in another module. Link Carbon Phases. It's Carbon That Makes Steel! Everybody involved in the early iron and steel industry knew that the there were pronounced differences between wrought iron, steel and cast-iron and that one could change the properties of these materials to a large extent.
One could even make steel from both wrough iron and cast-iron by some proper processing. Some of the practitioners of old must have given some thought to the question of what is responsible for the differences.
Unfortunately, none of them wrote it down, or if somebody did, it was lost. Most people thinking about that probably followed Aristotle and considered steel to be a more refined form of iron and thus were completely wrong. The question thus is: When did it become clear that steel is actually "dirty" iron, and that the most important dirt in this context was carbon?
It can't be otherwise. You cannot possibly figure out that carbon is the decisive element for steel making if you lack both: a valid concept of elements and an idea of what is carbon. He may not have been the first one to entertain this notion but he did clever experiments and wrote about it at length.
He is famous for a lot of other things but he seems to be the first proto scientist who conducted a systematic study into the production of steel. That wasn't just for fun.
In the early 18th century the French iron and steel industry was seriously backward, and the French, intend on conquering the world even so they lacked decent beer , needed decent hardware for fighting and shooting. Steel was produced by "cementation", i. It's however, not quite as obvious as it looks to us. Not knowing that wrought iron is rather pure iron, the cementation process could just as well have sucked something out of the wrought iron and thus turned it into steel.
Essentially he tried to change just one variable from experiment to experiment, exactly the right thing to do even in modern science. But sulfur? Looks like he didn't recognize that the essential stuff needed to make steel was actually carbon? Well - carbon hadn't been "invented" yet, look above. It didn't just mean the element sulfur S.
He investigated the structure of fractured iron and steel pieces and tried to explain a lot of things from the differences he observed iron - fibrous; steel - lamellar; cast-iron - granular; not too bad. Lacking a microscope and proper preparation methods, not to mention the concept of atoms, crystals, grains, and so on, he could not possibly arrive at the truth but got much closer than his contemporaries.
For example, he maintained that quenching changed the structure of the metal without putting some "vital juices" from the water into the steel. He also put an end to the mythology about quenching agents water, oil, blood, That is essentially correct.
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