Why is carbon chemistry called organic chemistry? How is nanotechnology related to carbon chemistry? How is carbon related to photosynthesis? How does carbon change into diamond? See all questions in Introduction to Carbon Chemistry.
Impact of this question views around the world. You can reuse this answer Creative Commons License. Without carbon, life as we know it could not exist. A compound is a substance that consists of two or more elements. A compound has a unique composition that is always the same. The smallest particle of a compound is called a molecule.
Consider water as an example. A molecule of water always contains one atom of oxygen and two atoms of hydrogen. The composition of water is expressed by the chemical formula H 2 O.
A model of a water molecule is shown in Figure below. Water is not an organic compound. A water molecule always has this composition, one atom of oxygen and two atoms of hydrogen.
The answer is chemical bonds. A chemical bond is a force that holds molecules together. Chemical bonds form when substances react with one another. A chemical reaction is a process that changes some chemical substances into others. News categories. Other top stories on FutureLearn. We explore the current business landscape in India, identity the 5 best startup opportunities and ….
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Before You Go! Diamonds and their inclusions have the potential to divulge how deep, how long ago and in what surroundings the diamonds grew. It turns out that all of these giants share a common, unexpected origin. For centuries, it was assumed that such magnificent gems are just large versions of more common, smaller stones.
Not so. Hints at a different genesis come from optical studies. Most diamonds, though stunningly transparent to visible light, absorb wavelengths of infrared and ultraviolet light as a consequence of impurities at the atomic scale.
Nitrogen atoms are the most common offenders. When those nitrogen atoms congregate into little clusters, they may impart a yellow or brown color to the gems. Nevertheless, the exact origins of Type II diamonds remained a mystery.
This research is a triumph on sociological as well as scientific grounds. Mine owners, gem cutters and collectors jealously guard their hoards; the bigger the diamond, the more difficult to gain access for scientific study.
To win the opportunity for even a cursory examination of inclusions in one or two big diamonds would be an unexpected treat for most scientists. Those who had tried, who caught brief glimpses of the silvery inclusions in big stones, mistakenly assumed them to be the common mineral graphite—a result that was not particularly newsworthy. The GIA, teaming up with other diamond experts from the United States, Europe and Africa, had laid the groundwork for studies at an altogether grander scale.
GIA certification is the universal standard of excellence for diamonds. From their numerous contacts at mines and museums, they were able to assemble and probe in detail an astonishing collection of gems and cutting fragments from 53 big Type II diamonds.
They even recut and polished five of the fragments to expose the silvery inclusions to the meticulous probing of advanced analytical instruments. The first surprise came from composition studies.
The inference: Big diamonds grow hundreds of miles beneath the surface in isolated mantle pockets of metal-rich liquid. Diamonds grow easily in such environments because iron metal has the unusual ability to soak up lots of carbon atoms.
At sufficient pressure and temperature, diamonds nucleate and grow, with mobile carbon atoms passing easily through the metal melt, adding layer upon layer to potentially giant crystals. But no one realized that nature had learned the same trick billions of years earlier.
The implications of this finding, that big diamonds have their own special provenance, go far beyond the quest for fancy gems. This distinctive population of Type II diamonds reveals a previously undocumented heterogeneity in the mantle.
Now, thanks to big diamonds and their telltale inclusions, we have clear evidence that the mantle is more like a fruitcake, with some relatively uniform regions but with swirls of novelty and lots of fruits and nuts read metal and diamonds thrown in.
We have long assumed that the mantle was made almost exclusively of oxygen-rich minerals. But metal inclusions point to other mantle zones that are devoid of oxygen—regions where different chemical processes can occur. We should not be coy about carbon and its role in climate change. Four facts are indisputable.
Fact one: Carbon dioxide and methane are potent greenhouse gases. Higher concentrations of carbon dioxide and methane in the atmosphere mean more solar energy is trapped. Fact three: Human activities, primarily the burning of billions of tons annually of carbon-rich fuels, are driving almost all of the changes in atmospheric composition.
Almost every scientist who has examined these compelling and unassailable facts arrives at the same unambiguous conclusion.
Human activities are causing Earth to heat up. This conclusion is not a matter of opinion or speculation. It is not driven by politics or economics. It is not a ploy for researchers to obtain more funding or environmentalists to revel in hyperbolic press coverage. Some things about Earth are true and this is one of those things. Carbon chemistry pervades our lives. Almost every object we see, every material good we buy, every bite of food we consume, is based on element six.
Every activity is influenced by carbon—work and sports, sleeping and waking, birthing and dying. And what of other pursuits? What of music? A symphony orchestra—every section, every instrument—sings a song of carbon.
The string section—violins and violas, cellos and basses—are composed almost entirely of carbon compounds: Wooden belly, fingerboard, sound post, pegs and tailpiece; gut strings, horsehair bow and plastic chin rest.
String instruments also depend on slippery grease for the pegs and sticky rosin for the bow.
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