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.
Its high thermal conductivity and electrical insulation cry out for uses in high powered electronics. Its optical properties are ideal for windows and lenses and its biocompatibility could be exploited in coatings for implants.
These properties have been known for centuries - so why then is the use of diamond not more widespread? The reason is that natural diamond and diamonds formed by high pressure high temperature synthesis are of limited size - usually a few millimeters at most, and can only be cut and shaped along specific crystal faces.
This prevents the use of diamond in most of the suggested applications. However, about 20 years ago scientists discovered a new way to synthesise diamond this time under low pressure, high temperature conditions, using chemical vapour deposition. If one were to consider the thermodynamic stability of carbon, we would find that at room temperature and pressure the most stable form of carbon is actually graphite, not diamond.
Strictly speaking, from a purely energetic or thermodynamic point of view, diamond should spontaneously turn into graphite under ambient conditions! Clearly this doesn't happen and that is because the energy required to break the strong bonds in diamond and rearrange them to form graphite requires a large input of energy and so the whole process is so slow that on the scale of millennia the reaction does not take place. It is this metastability of diamond that is exploited in chemical vapour deposition.
The carbon-based molecules then deposit on a surface to form a coating or thin film of diamond. Actually both graphite and diamond are initially formed, but under these highly reactive conditions, the graphitic deposits are etched off the surface, leaving only the diamond.
The films are polycrystalline, consisting of crystallites in the micron size range so lack the clarity and brilliance of gemstone diamond. While they may not be as pretty, these diamond films can be deposited on a range of surfaces of different size and shapes and so hugely increase the potential applications of diamond. Challenges still remain to understand the complex chemistry of the intercrystalline boundaries and surface chemistry of the films and to learn how best to exploit them.
This material will be keeping chemists, materials scientists, physicists and engineers busy for many years to come. However, at present we can all agree that there is more to diamond than just a pretty face! Katherine Holt extolling the virtues of the jewel in carbon's crown. Next week we're heading to the top of group one to hear the story of the metal that revolutionised the treatment of manic depression.
Its calming effect on the brain was first noted in , by an Australian doctor, John Cade, of the Victoria Department of Mental Hygiene. He had injected guinea pigs with a 0. Cade then gave his most mentally disturbed patient an injection of the same solution. The man responded so well that within days he was transferred to a normal hospital ward and was soon back at work.
And it's still used today although despite 50 years of medical progress we still don't know how it works. That was Matt Wilkinson who will be here with the story of Lithium on next week's Chemistry in its Element, I do hope you can join us.
I'm Chris Smith, thank you for listening and goodbye. Chemistry in its element is brought to you by the Royal Society of Chemistry and produced by thenakedscientists. There's more information and other episodes of Chemistry in its element on our website at chemistryworld.
Click here to view videos about Carbon. View videos about. Help Text. Learn Chemistry : Your single route to hundreds of free-to-access chemistry teaching resources. We hope that you enjoy your visit to this Site. We welcome your feedback. Data W. Haynes, ed. Version 1. Coursey, D. Schwab, J. Tsai, and R. Dragoset, Atomic Weights and Isotopic Compositions version 4.
Periodic Table of Videos , accessed December Podcasts Produced by The Naked Scientists. Download our free Periodic Table app for mobile phones and tablets. Explore all elements. D Dysprosium Dubnium Darmstadtium. E Europium Erbium Einsteinium. F Fluorine Francium Fermium Flerovium. G Gallium Germanium Gadolinium Gold.
I Iron Indium Iodine Iridium. K Krypton. O Oxygen Osmium Oganesson. U Uranium. V Vanadium. X Xenon. Y Yttrium Ytterbium. Z Zinc Zirconium. Membership Become a member Connect with others Supporting individuals Supporting organisations Manage my membership. Facebook Twitter LinkedIn Youtube. Discovery date. Discovered by. Origin of the name. Melting point. Boiling point. Atomic number. Relative atomic mass. Key isotopes. Electron configuration. CAS number. ChemSpider ID. ChemSpider is a free chemical structure database.
Electronegativity Pauling scale. Covalent bond. Found in. CCl 4. CH 3 OH. Common oxidation states. Atomic mass. Half life. It is a transparent material that can split a single beam of light into two beams, a property known as birefringence. Very little is known about this form of carbon. Large molecules consisting only of carbon, known as buckminsterfullerenes, or buckyballs, have recently been discovered and are currently the subject of much scientific interest.
A single buckyball consists of 60 or 70 carbon atoms C 60 or C 70 linked together in a structure that looks like a soccer ball. They can trap other atoms within their framework, appear to be capable of withstanding great pressures and have magnetic and superconductive properties. Carbon, a radioactive isotope of carbon with a half-life of 5, years, is used to find the age of formerly living things through a process known as radiocarbon dating.
The theory behind carbon dating is fairly simple. Scientists know that a small amount of naturally occurring carbon is carbon Although carbon decays into nitrogen through beta decay , the amount of carbon in the environment remains constant because new carbon is always being created in the upper atmosphere by cosmic rays.
Living things tend to ingest materials that contain carbon, so the percentage of carbon within living things is the same as the percentage of carbon in the environment. Once an organism dies, it no longer ingests much of anything.
The carbon within that organism is no longer replaced and the percentage of carbon begins to decrease as it decays. By measuring the percentage of carbon in the remains of an organism, and by assuming that the natural abundance of carbon has remained constant over time, scientists can estimate when that organism died. For example, if the concentration of carbon in the remains of an organism is half of the natural concentration of carbon, a scientist would estimate that the organism died about 5, years ago, the half-life of carbon There are nearly ten million known carbon compounds and an entire branch of chemistry, known as organic chemistry, is devoted to their study.
Many carbon compounds are essential for life as we know it. For that you needed to have a few vents in the mud cover, and the initial burning proper produced the heat to get the pyrolysis going in the larger part of the pile. The pictures below show what a charcoal pile looked like since about 1. Before that, the wood was simply thrown into a pit in the earth, set on fire and then covered to prevent all-out burning.
Charcoal making Next, the pile will be covered with earth. As soon as the process has been started around o C o F , it is self-supporting since pyrolysis generates heat of its own and thus raises the temperature. The process continues until all the wood has been converted. As a rule of thumb, 5 tons of wood make 1 ton of charcoal. Of course, since wood contains more stuff besides the major ingredients listed above, all the non-burnable stuff called " ashes " in burning proper is now contained as dirt in the charcoal.
Have you ever wondered why flour mostly starch in Germany has always a number on it like "type " or "type "? This number just gives the weight of the remaining ash in milligram mg if you burn grams g of the flour. The more ash, the more minerals are in there. For some odd reason my wife thinks that ash is good for you when she uses flour for baking. Wood ashes consist mainly of oxides of calcium Ca , potassium K and magnesium Mg.
Charcoal retains the original cell structure of the wood and thus is very porous or, in other words, has a large surface-to-volume ratio. That's why it burns far better and hotter than wood or regular coal. There is simply more surface area where the process can take place; see below:. Charcoal probably from pine conserved in slag during early iron smelting. Source: Vagn Buchwald's wonderful book.
Of course, ever-present " sympathetic magic " was invoked to relate hard iron to charcoal made from hard wood and soft iron to charcoal from soft wood, etc. It is true to some extent that charcoal made from hard wood might make your iron hader, i.
It was a good idea to be very concerned about the charoal that you used in your smelter, and smelter operators had a strong tendency to never chane a "winning team". When metal smelting became a major industry, let's say ever since BC, de-forestation became a problem. Wood or charcoal had to be transported over ever increasing distances, and there is some speculation that the depletion of wood resources lead to the decline of whole empires, e. Charcoal burners or Charburners were a-plenty in ancient metal-working society but their profession usually had a somewhat seedy reputation.
Of course, throughout most of history, the useless but powerful nobility looked down on manual labor anyway, and the appearance of always black and dirty charburners did not particularly recommend them as good companions. In a few areas around the globe raw diamonds could be found just so; in particular, it appears, in deposits of some Indian rivers. Diamonds have been known in India for at least 3, years, maybe even 6.
What exactly people did with them is unclear. They were used as uncut gemstones , religious icons whatever that might be and as tools for scratching and working hard things. I would guess that it is the same root as "atomos", meaning indivisible or uncuttable, which gave us the "atom" - but it is all Greek to me. Diamonds have a simple cubic face-centered fcc structure like silicon Si or germanium Ge as shown below. Blue and green spheres mark the position of carbon atoms, the blue spheres mark also the position of lattice points.
Red lines show the bonds between atoms. The black lines are meaningless , they just guide the eye to identify the cubic structure.
A Chinese work from the 3rd century BC refers to diamonds as amulets of foreigners warding off evil influences while the Chinese themselves used imported diamonds as tools for working jade. While diamonds for millennia came mostly from India, Brazil major finds in and South Africa major finds in Kimberley eventually took over.
Small numbers of diamonds began appearing in European jewelry in the 13th century; they were used as "accent points" among pearls set in gold. Louis IX of France 13th century reserved diamonds for the king by law, demonstrating that this piece of carbon was now seen as extremely valuable. The big days of diamond , lasting until today, started when the facetted cut that we have today as a matter of course was invented by Jules Cardinal Mazarin in the 17th century.
Diamonds are a metastable phase of carbon; the stable phase is hexagonal graphite. The formation of diamonds therefore requires very specific conditions: rather high pressure around 5 GPa and high but not excessively high temperatures around 1. That makes it rather difficult to grow big single diamond crystals in the laboratory.
On the other hand, making small diamonds or coating all kinds of materials with a thin layer of diamond is now commercial routine. The black stuff left in your oven, after doing your turkey or whatever, contains what one could call "amorphous diamond" with a lot of strong diamond-like bonds. It is thus not surprising that this annoying matter is very hard and durable and almost impossible to scratch off or to dissolve in chemicals that don't tend to kill you on the side.
Coal is the black stuff we dig out of the ground in ever increasing quantities. The table below lists the 8 biggest producers; there are of course many more. Country Most of that coal ends up as carbon dioxide CO 2. Frightening, isn't it? A lot of this is used to produce the - roughly - 1. In some areas of the world coal seams came out of the ground, and coal then was just dug out and used on a small scale, e.
While much of its use remained local, a lively trade developed along the North Sea coast supplying coal to Yorkshire and London. This also extended to the continental Rhineland, where bituminous coal was already used for the smelting of iron ore. Smelting iron ore with bituminous coal, or any coal for that matter, would generate very inferior steel because of the sulfur problem. My guess is that smelting and melting have been confused once more. Major use of coal started when Great Britain had finally cut down most of its forests in the 16th century.
The use of coal as domestic fuel rapidly expanded, as did the diseases caused by the smoke. The industrial revolution in the 19th century finally led to an explosive growth of coal mining that has essentially continued to this very day.
Coal, mind you, is not a well defined substance and it is not carbon as already pointed out above. The non-coal stuff contains mostly oxygen and hydrogen. The figure below gives a schematic view of the composition of coal. Source: Adopted from wikipedia; Obscure old Russian text book from A. If there would only be ordered arrays of those hexagons, it would be pure graphite. Wherever two lines meet in the upper picture sits a carbon atom and a hydrogen atom mostly not drawn. Where three lines meet is only a carbon atom.
One could also say that it relates to coal the same way charcoal relates to wood. Coke here, to be perfectly clear, is not something you snort up your nose. In a nutshell: coke results when you pyrolyze coal. Rather pure carbon is left over, and as a by-product coal-gas , and coal-tar are produced in large quantities. These by-products created their own industries. Coal gas also called town gas and illumination gas was the primary source of gaseous fuel for lighting, cooking and heating in many cities in the 18th and 19th century.
Coal tar was used for making all kinds of early organic compounds like creosote. Nobody heeded his idea, of course, until the need to have something that could replace charcoal became a matter of life and death.
Charcoal was becoming expensive in merry old England in the 16th century because the forests were mostly cut down by then, and that meant that metal smelting became expensive.
Well, yes, but who cares? Far worse was that beer brewing and thus beer became expensive, because you need a good fuel to roast the malt needed for making beer! You just can't run a decent civilization that smelts metals and is bent on conquering the world or at least the French without large quantities of good and affordable beer, as I have ascertained before.
Using coal for roasting the malt impairs a foul taste to the beer because of the sulfur in the coal. Making coke became imperative, and beer brewing with coke started in Derbyshire for good. Of course, after the bulk supply of beer was ensured, coke could then also be used to smelt metals, make swords and later guns, and all the other hardware needed for conquering the world.
It took a while, however. It took even longer before that caught on - only around pretty much all blast furnaces were run on coke. Some charcoal fanatics, however, where not convinced even then and kept their smelters on charcoal well into the 20th century. The Chinese did it the wrong way around. They started to make coke already in the 9th century AD but didn't use it for making first beer and then iron.
They somehow got confused and started smelting iron with coke right away. In the 11th century they had a major iron industry running that was based on coke and not just charcoal. That kept them so busy that they never got around to making decent beer. Poor suckers, it was downhill ever since.
They could have conquered the world quite easily in the 15th century, long before the Spaniards and Portuguese made their bid, because they had superior hardware and ships, and many other advanced things like live-in concubines. Fortunately for us , they didn't have the balls beer needed for some conquering. Now look at the British and the Germans. They focussed on beer for quite a while - and the British eventually did conquer most of the world and they still feel good about that!
We Germans weren't quite that successful but at least we tried. The Americans today have some success, but their conquering-the-world efforts get rather mixed reviews.
I blame it on the quality of their beer. Graphite is the stable phase of carbon with a hexagonal lattice. It is not a simple hexagonal close-packed structure but a bit more complicated as shown below. The bonds in the hexagonal plane are very strong just like in diamond, while the bonds between the planes are very weak. That's why it is very easy to deform graphite in directions parallel to the hexagonal planes and very difficult in directions perpendicular to it.
That allows applications that are breathtakingly different: Use poly-crystalline graphite. Whenever you press or pull on it, some areas shift easily and stick to the contact material. This is great for making pencils or lubricants. Use monocrystalline graphite in long fibres oriented in the hexagonal plane.
When you pull at the fibres, you are trying to break diamond bonds and that is tough to do. Now protect your fibres from forces at right angles by encasing them in some epoxy. You have made carbon-fiber-reinforced polymer or plastic CFRP or CRP with a strength-to-weight ratio that exceeds the best steels by far.
The name " graphite " was coined by one Abraham Gottlob Werner in from what else? This already gives a hint that there was some confusion as to the nature of the stuff in pencils. People thought for a long time that natural graphite was some lead mineral.
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