What is Carbon: Definition and 519 Discussions

Carbon (from Latin: carbo "coal") is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes up only about 0.025 percent of Earth's crust. Three isotopes occur naturally, 12C and 13C being stable, while 14C is a radionuclide, decaying with a half-life of about 5,730 years. Carbon is one of the few elements known since antiquity.Carbon is the 15th most abundant element in the Earth's crust, and the fourth most abundant element in the universe by mass after hydrogen, helium, and oxygen. Carbon's abundance, its unique diversity of organic compounds, and its unusual ability to form polymers at the temperatures commonly encountered on Earth enables this element to serve as a common element of all known life. It is the second most abundant element in the human body by mass (about 18.5%) after oxygen.The atoms of carbon can bond together in diverse ways, resulting in various allotropes of carbon. Well-known allotropes include graphite, diamond, amorphous carbon and fullerenes. The physical properties of carbon vary widely with the allotropic form. For example, graphite is opaque and black while diamond is highly transparent. Graphite is soft enough to form a streak on paper (hence its name, from the Greek verb "γράφειν" which means "to write"), while diamond is the hardest naturally occurring material known. Graphite is a good electrical conductor while diamond has a low electrical conductivity. Under normal conditions, diamond, carbon nanotubes, and graphene have the highest thermal conductivities of all known materials. All carbon allotropes are solids under normal conditions, with graphite being the most thermodynamically stable form at standard temperature and pressure. They are chemically resistant and require high temperature to react even with oxygen.
The most common oxidation state of carbon in inorganic compounds is +4, while +2 is found in carbon monoxide and transition metal carbonyl complexes. The largest sources of inorganic carbon are limestones, dolomites and carbon dioxide, but significant quantities occur in organic deposits of coal, peat, oil, and methane clathrates. Carbon forms a vast number of compounds, more than any other element, with almost ten million compounds described to date, and yet that number is but a fraction of the number of theoretically possible compounds under standard conditions. For this reason, carbon has often been referred to as the "king of the elements".

View More On Wikipedia.org
  1. .Scott

    Cement Capacitors based on carbon black and concrete for use in energy storage

    A recent article published in the Proceedings of the National Academy of Sciences (PNAS) describes a large electric capacitors based on carbon black and concrete. The device would be used for electric power storage - often in proximity to the electric power demand, for example, a home.
  2. jianggong

    14MeV neutrons in MCNP interact with carbon without producing alpha

    14MeV neutrons in MCNP interact with carbon without producing alpha particles and protons, yes Questions about my cross section data? I've tried ENDFB8/B7.1, JEFF3.3, JENDL5, CENDL3.2 without any results, but if you use phys:n model, it looks like alpha particles will be produced, but it doesn't...
  3. P

    Biology Why do fatty acids burn in the presence of carbon?

    Hi everyone! Do you know why fatty acids burn in the presence of carbon? I found some explanations on the internet but they didn't help me. Can you explain me (in simple terms) why fatty acids burn in the presence of carbon ?
  4. B

    Will charcoal (carbon) oxidize in the air?

    Wikipedia — Carbon sequestration claims that burying charcoal into the soil offsets CO2 and thus reduces the greenhouse effect: Is it a must to cover charcoal/biochar with the soil to prevent the air and rain water exposure to avoid oxidation, i.e. offset carbon dioxide? Would it otherwise...
  5. abdulbadii

    Galvanized Steel vs High Carbon Steel: Mechanical Performance

    In what condition and how definitively galvanized steel is lower in mechanical performance and counts to be ruled out replacing high carbon steel ?
  6. Graeme M

    Methane and the Carbon Cycle

    I am aware that it is claimed that ruminant farming and animal agriculture more generally are significant contributors to anthropogenic emissions. Here in Australia, for example, about 80% of emissions from the ag sector are from methane and nitrous oxide. Various groups propose finding ways to...
  7. A

    I What group might represent the symmetries of these carbon rings?

    The carbon rings in the upper-middle of this page https://www2.chemistry.msu.edu/faculty/reusch/virttxtjml/react3.htm such as corannulene or coronene possess symmetries. But, they are not the typical dihedral arrangements of points, like a single hexagon or single pentagon or single equilateral...
  8. Nicole4Jesus

    Non-Flammable carbon deposit cleaner

    How did you find PF?: I found Physics Forum in a Google search in hopes to find a non flammable solution to dissolve carbon deposits on a propane fueled water heater pilot light. I found a forum post about dissolving carbon deposits on spark plugs. Which I did find helpful somewhat but the...
  9. PainterGuy

    Shouldn't they use carbon dioxide monitors?

    Hi, In many places in the US the carbon monoxide monitors are mandatory to be installed inside residential places. Source: www.kidde.com/home-safety/en/us/co-safety/carbon-monoxide-alarm-faqs/ Source: https://www.health.ny.gov/publications/2826.pdf Source...
  10. K

    Producing Renewable Liquid Fuels from Atmospheric Carbon Dioxide

    The Sasol plants in South Africa are producing liquid fuels using coal and water as the source of energy and syngas, CO and H2. Some refineries are using natural gas as the starting fuel to produce liquid fuels. Both of these processes are not renewable. The US Navy has a process to extract CO2...
  11. B

    (Moved) Mass Algae Farm for Carbon Sequestration

    Summary:: Not looking for concrete answers, just want to spitball some ideas about the basics of Algae cultivation and implications of scaling to large scale. So the idea is this: Build massive ponds and seed them with an initial culture of algae. Wait one doubling period and filter out half...
  12. A

    Wood as a carbon neutral biofuel

    Moderator’s note: discussion spun off from https://www.physicsforums.com/threads/the-nuclear-power-thread.9091/page-43#post-6558385 Sometimes I don't understand the Germans, so technically advanced and forward thinking and yet somehow willing to abandon logic on this one. Their alternative is...
  13. P

    A Phase diagram of Carbon at large electric fields.

    I am wondering if the phase diagram of Carbon has been explored at very large electric fields. Can one make any theoretical guesses ? In specific I am interested in Pressure Vs Electric field and Electric field vs Temperature at fixed temperature and pressure respectively.
  14. C

    Chemical/Paint Algae Carbon Capture: Make Your Own Algae Tank & Absorb CO2

    I'm just devastated by the news of climate change as of late, and I knew it was worrying but I've never been more worried about it in my life than I am right now. Have we truly passed the point of no return? Are we all doomed? Or do we still have time? Is algae carbon capture the way out? And...
  15. D

    Atmospheric carbon ratios

    I'm wondering if anthropogenic climate change (C13: C14 and C14:C12 ratios) is still contentious on these forums. Counting the amount of fossil emissions in the last 100 years isn't particularly difficult, and matching the curve with NOAA measurements seems trivial, so I'm wondering what kind of...
  16. S

    Chemistry Deciding Carbon Numbering for (Z)-1-bromo-2-chloro-2-fluoro-1-iodoethene

    The following structure was given, and the answer was (z)-1-bromo-2-chloro-2-fluoro-1-iodoethene. But how do you decide which carbon is numbered 1 and the other 2? Thank you.
  17. Q

    B Why is Carbon considered volatile?

    Carbon is considered volatile by planetary science, eg Moon lacks volatiles and thus lacks carbon. However volatiles are defined as "elements or substances with low boiling point", but Carbon boiling point is very high! Its sublimation point is 3900K, so it should be refractory and not volatile...
  18. Urgentt

    L type activated carbon -- is it hazardous?

    Hello i Tried to clean my activated carbon ,washed then put on oven then cool with water again. Is it possble to make anything other than CO2 this way? I read l type is something similar is that hazardous?
  19. Astronuc

    B Phys.org - Carbon creation finding set to rock astrophysics

    https://phys.org/news/2020-10-carbon-creation-astrophysics.html Back in 2016 - Recent results in nuclear astrophysics https://arxiv.org/abs/1605.07810 From the abstract -
  20. AN630078

    Elastic Collision of Hydrogen and Carbon Atoms

    1.p=mv Before the collision: p hydrogen = 1.7x10^-27 * 500 =8.5*10^-25 kg ms^-1 p carbon = 2.0x10^-26 * 0 = 0 kg ms^-1 p total before = 8.5*10^-25 kg ms^-1 The sum of momentum prior to the collision is equal to the total momentum after a collision, momentum is constant, therefore; p before = p...
  21. Khatti

    What's going on with mining carbon from the atmosphere?

    <Mentor moved thread to Science Fiction> Hello one and all. I'm fascinated by the idea of breaking down methane and carbon dioxide and using the carbon as a building material (graphene being the preferred material rendered from this process). Can anyone tell me anything on where the current...
  22. G

    Vacuum Tank Query (Aluminium, Carbon Fibre, etc, Composition)

    Hi, I'm hoping this will be a fairly easy question for someone on here to answer. If I wanted to make a (small?) vacuum tank (basically a hollow cylinder capped with two similarly hollow hemispheres - like so: (===)), how thick would the walls of the tank need to be for it to withstand the...
  23. eedftt

    What is the orbital radius of a muon captured in the n=1 ground state of Carbon?

    The muon is a subatomic particle with the same charge as an electron but with a mass that is 207 times greater: mμ=207me. Physicists think of muons as "heavy electrons." However, the muon is not a stable particle; it decays with a half-life of 1.5 μs into an electron plus two neutrinos. Muons...
  24. B

    Finding the activity of a carbon 14 sample

    Hi there So I have had a go at this question but I'm not confident that I have done the last 2 parts of this question right? Can anyone please see if this is what you do to get the values? Any help would be appreciated! Thanks
  25. J

    Extremely hydrogenated carbon compounds

    I am doing some theoretical free-lance work on prospects of chemical rocket fuels with unusually high heating values and specific impulses. One of my latest interests is prospects for using fuels with molecules made of one carbon atom and 5 or more hydrogen atoms. Specific examples I am...
  26. VictorMedvil

    A What is the energy release of the CNO cycle in carbon fusion?

    I would like details on CNO Cycle Carbon Fusion about the exact energy release of an entire cycle through the reaction and other details you would think would be important about the CNO cycle.
  27. M

    Altered Carbon Season 2 -- Better to have read the novel or not?

    I love Morgan's Takeshi Kovacs character, and after Netflix serialized Altered Carbon in 2018, I went back and read all three novels again: Altered Carbon, Broken Angels, and Woken Furies. Netflix has now released season two of Altered Carbon, which seems so nominally based on Broken Angels...
  28. L

    SSD crash after Windows 10 update on Lenovo Thinkpad X1 Carbon 5th Gen

    Hi all, I have a laptop Lenovo Thinkpad X1 Carbon 5th Gen (Intel(R) Core(TM) i7-7500U CPU @ 2.70GHz 2.90 GHz, 8 GB RAM). It was bought with Windows 10 OS installed on SSD 512 GB (model of the disk is SSDPEKKF512G7L). Since the 1st running, the laptop was constantly heating and fan made much...
  29. C

    Can wearing N95 mask make you inhale the exhaled carbon dioxide?

    1. Can wearing N95 mask make you inhale the exhaled carbon dioxide? 2. Does it only protect against dusts or also bacteria or viruses? N95 can protect against 3 micron or larger. What are the sizes of bacteria or viruses?
  30. NTL2009

    Carbon Microphone & Loudspeaker History: Chicken/Egg?

    I recently watched a YouTube video on the history of the telephone. It was fairly generic, stuff I knew, but he spent some time on the carbon microphone, which made me curious about the real details of the development of carbon microphones. I easily found lots of info with a search. But that...
  31. nilsvoorkamp1

    Friction: aluminium on carbon

    I need the coefficient of kinetic friction for movement between greasy aluminium on carbon. It's nowhere to be found on the internet. Thanks in advance!
  32. kevinmorais

    Can Gases be Carbon Dated?

    Can we Carbon Date a Gas or must it always be a solid?
  33. Ygggdrasil

    Scientists engineer E. coli that eats carbon dioxide

    E. coli is one of the best studied and most widely used bacteria in biotechnology. This week, published in the journal Cell, researchers report having engineered the bacterium to be able to generate all of its carbon from CO2, opening the way toward using these bacteria for replacement of...
  34. kevinmorais

    B How does carbon 14 have such a perfect halflife?

    Summary: How do the atoms know which ones must decay first in carbon 14 Summary: How do the atoms know which ones must decay first in carbon 14 Carbon 14 has a half life of 5700 years. How do the Atoms know which ones will decay as we have such a perfect half life, why don't they all just...
  35. A

    Carbon atom larger than a water molecule? Measuring a molecule's size?

    So there's a website here: https://learn.genetics.utah.edu/content/cells/scale/ That shows the scale of various entities (coffee bean, viruses, a carbon atom, a water molecule etc). It says that the carbon atom is larger than the water molecule. This is based on the 'van der waal radius'...
  36. G

    Negative carbon emissions to fight ocean acidification?

    The IPCC report strongly encouraged not only trying to get our carbon dioxide emissions down to fight climate change, but to go into negative emissions so as to draw the carbon dioxide out of the air (since it's too high as it is). Wouldn't that help to fight ocean acidification too? Because...
  37. J

    1018 carbon steel tensile test explanation

    Tensile tested 2 samples of 1018 unheat treated carbon steel, assumed to be very similar steel (bought from same place, same order, ect) but very different tensile test results. The results of the tensile test can be seen below as well as a few calculated values. I do not know what this would be...
  38. insanul

    Term Symbol of Carbon & Configuration Explanation

    A ground state configuration table for carbon is shown below. I am wondering why although configuration 4 and 5 share the same ML and MS ,they belong to different energy levels 1D2 and 3P2. It is just randomly chosen or they do have some rules? What cause the difference of energy levels of No.3...
  39. C

    Carbon sequestration, how does it work? Is it practical?

    Hi All, I understand carbon sequestration in the simplest sense is capturing and storing carbon. As seen in the title, I'm going to split this into two sections. i) How does it work? I imagine that trees, in a sense are doing this. They take in the carbon from our atmosphere and is stored...
  40. dsilvas

    Solving the Mystery: Exploring E << m Condition for Carbon 12 Ions

    Clarification: The statement in the title is actually from the solution to the homework question, as given by the textbook (you can see the whole thing below under "Textbook solution"). The solution doesn't explain everything, which is where my confusion comes from. Usually in my classes we...
  41. DEvens

    Is there an alternate fuel that de-emphasizes carbon?

    Is there a potential fuel, for some kind of engine, not necessarily similar to existing car or diesel engines, that does not have carbon in it? That is, that you might manufacture from water and air without having to concentrate the carbon dioxide somehow. And that's liquid at ordinary...
  42. L

    Is the initial dark carbon water from a purifier safe to drink?

    Please see attached pictures. Whenever we replace the right cartridge (with carbon filter) with new one (every 6 months). There are initial dark tint water from the carbon that fills a basin. Are the dark water safe? We throw the water of course. But there maybe those who didn't know or have...
  43. S

    Mosquitoes attracted by carbon dioxide?

    It's commonly said that mosquitoes are attracted by carbon dioxide - so I'll guess that there's empirical evidence for that assertion. But is the mechanism for this known? What is the localized concentration of carbon dioxide around a person respiring at a normal rate? Do we know that it's...
  44. J

    Standard enthelpies of formation of carbon nanotubes etc.

    I am curious about the standard enthalpies of formation of carbon nanotubes, diamond, carbon buckyballs, graphene, etc. I read from physics forums that the standard enthalpies of formation of these allotropes of carbon are small. However, since diamond is fabricated naturally under extreme...
  45. J

    What is the heat of combustion of 1 kg carbon dioxide w/ magnesium?

    I am trying to find out the heat of combustion of one kilogram of carbon dioxide with magnesium. I am looking for results for stochiometric conditions of these two reactants. I have found the following equation online 2 Mg(s) + CO2 ---> 2 MgO(s) + C(s) yields a standard enthalpy of --810.1...
  46. U

    Carbon fiber's EM parameters

    I would like to know parameters of this material, such as: ##\epsilon##, ##\mu## and ##\sigma##, for EM simulations with CST. I can't find anything similar to carbon fibers or general plastic in the CST material library. Google is not helping me this time. Does anyone know something more on this...
  47. John Lutz

    Styrene to inert Hydrogen and inert Carbon

    If you remove (seperate) all 8 hygrogens of atypical polymer Styrene. Does is make both inert Carbon and inert Hydrogen? Thank you! John