Talk:Carbon monoxide/Archive 1

Hemoglobin
"It binds very strongly to the iron atom in hemoglobin, (the principal oxygen-carrying compound in blood); this renders the hemoglobin incapable of taking up and releasing oxygen."
 * Wouldn't it be more precise to say : "It has stronger affinity for the iron binding site in hemoglobin, (the principal oxygen-carrying compound in blood); this renders the hemoglobin's oxygen transporting function practically ineffective."

QUESTION: at what rate does CO leave the bloodstream? To what extent is carbon monoxide "poisoning" cumulative...like, say, lead poisoning? —Preceding unsigned comment added by 69.107.74.160 (talk • contribs) 16:59, 25 February 2005

holocaust
How does carbon monoxide damage the body by smoking? —Preceding unsigned comment added by 82.13.83.193 (talk) 15:23, 6 June 2010 (UTC)

I read somewhere that 'monoxide gas' was used in the holocaust. Does anyone know if it was this stuff or a different 'monoxide'

It's carbon monoxide.

thanks tommylommykins 14:43, July 18, 2005 (UTC)

They also often used hydrogen cyanide (or possibly cyanogen). Anthony Appleyard 15:19, 1 September 2005 (UTC)

Erm.. It wasn't always like that, Zyklon B was mostly used. Kilo-Lima 21:03, 13 October 2005 (UTC)


 * Zyklon B is hydrogen cyanide
 * Well, if you believe some accounts CO was even more commonly used then Zyklon B (HCN). In most of the cases it is claimed that diesel engines engines were used to gas prisoners. The claim is made, despite the fact that petrol engines generate by far higher concentrations of CO. The then in use "Holzvergaseer" engines are require to produce even more then that. Perhaps the article should focus a bit on the generation of CO by diesel engines, petrol engines and the "Holzvergaser" engines? --41.15.221.94 (talk) 21:57, 3 February 2009 (UTC)
 * What about hydrogen sulfide; isn't that more toxic than CO (and similar to HCN in toxicity)? Stonemason89 (talk) 04:02, 8 February 2010 (UTC)

density
8.0 kg/cm3, cannot be correct, no natural stuff on Earth is so heavy!

Neurotransmitter
Shouldnt it be mentioned as well that it's a gas neurotransmitter somewhere? -- Random viewer...

Bond length
The listed bond length in the article is incorrect. Any college student silly enough to use this article as a reference for their laboratories deserves the grade they receive, which will not be a good one.


 * Quite curiously, Mr./Ms. Anonymouse didn't put in his/her thoughts of what the answer should be, so that we could grade it. Would it be farther off than what's here now?  Just wondering.  If a student were trying to measure this, and used the Wikipedia article to check their work, is it likely that they'd be led astray?  Pretty unlikely. Gene Nygaard 03:33, 4 Apr 2005 (UTC)


 * Yet the question still has not been answered. I work around older IC Engines without Catalytic converters. Even with good ventilation there is still some level of CO in the area. Without hyperbaric treatment how long does it take low levels of CO bonding to dissipate. Ie. If one were exposed to an atmosphere of 20 PPM for 3 or 4 hours daily for 3 or 4 days, how long should one wait before again exposing ones self to those levels? (My work around old engines is a hobby, I can take extended breaks doing other things between times that I require them to actually be running for testing.) My Google searches have not yet turned up a substantial answer. [Gerald Livingston] 65.170.133.234 19:25, 8 November 2005 (UTC)


 * My understanding of CO poisoning is that it permanently (or near as dammit) binds to haemoglobin, writing that particular molecule off to Oxygen for the rest of its lifetime. That is to say, the effects are cumulative (which is what makes it so deadly). This being said, the red blood cells in your body are in a constant state of renewal, with a ballpark figure of a completely new set of blood cells every 6 weeks, so it's not as bad as all that. (A chemistry student, Cambridge University) 128.232.242.158 22:04, 9 November 2005 (UTC)


 * Your understanding is correct; the compound it forms is called carboxyhemoglobin, and it doesn't help your circulatory system one bit. Ruff Bark away!


 * It is not. CO does not bind permanently. CO-Intoxication is cured by supplying 100% O2 for breathing which removes the CO from your blood completely (though not within seconds). The danger comes from CO's ability to bind much better than O2, thus displacing O2 as long as enough CO is available in the air. --84.159.176.234 20:53, 10 November 2007 (UTC)

Carbon monoxide poisoning
Anybody object if I split that into a separate article? --Arcadian 02:38, 20 July 2005 (UTC)
 * Please do, but clearly mark the link. That's what I came here looking for actually!
 * Okay, I've split it out into Carbon monoxide poisoning (which was formerly a redirect). --Arcadian 17:30, 21 July 2005 (UTC)

Images
What causes the two hotspots in CO-concentration over AFrica and South America?
 * Wildfires.--NHSavage 16:35, 20 May 2006 (UTC)

Confusion
"Under ordinary conditions, it is less dense than air. During fires, it accumulates on the ground, so that if poisoning causes loss of consciousness, the amount of carbon monoxide inhaled increases and so fatality is radically increased." This seems a little confusing to me, does the density of CO become higher than that of air as the temperature increases? Terri G 17:59, 26 July 2006 (UTC)

How do detectors work?
How do CO detectors work? I'm told there are "electrochemical" and "MOS" varieties. -- Beland 05:08, 18 September 2006 (UTC)

See Carbon monoxide detector. -69.87.199.142 23:31, 23 August 2007 (UTC)

Rainbow image??
I'm curious: Why the rainbow image next to the space-filling model of carbon dioxide? Ruff Bark away! 21:14, 28 October 2006 (UTC)

That is the key - it tells you what colours represent what densities of CO MilleauRekiir 15:27, 1 February 2007 (UTC)

Edit to toxicity
Edited toxicity - removed the blurb about hemoglobin, and linked to the hemoglobin article. That does a better job, methinks. =^^= --Dennis The TIger 22:58, 12 March 2007 (UTC)

recommendation for improvement
I just added some peerreviewer recommendations for further article improvement in the WP:Chem template. Wim van Dorst (Talk)'' 22:29, 5 April 2007 (UTC).

Fair use rationale for Image:Chp co ligand.jpg
Image:Chp co ligand.jpg is being used on this article. I notice the image page specifies that the image is being used under fair use but there is no explanation or rationale as to why its use in Wikipedia articles constitutes fair use. In addition to the boilerplate fair use template, you must also write out on the image description page a specific explanation or rationale for why using this image in each article is consistent with fair use.

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If there is other other fair use media, consider checking that you have specified the fair use rationale on the other images used on this page. Note that any fair use images uploaded after 4 May, 2006, and lacking such an explanation will be deleted one week after they have been uploaded, as described on criteria for speedy deletion. If you have any questions please ask them at the Media copyright questions page. Thank you.BetacommandBot 20:17, 2 June 2007 (UTC)

Real-world concentrations
Please add some real-world concentration numbers, typical CO ppm ranges: -69.87.199.142 00:19, 24 August 2007 (UTC)
 * atmosphere: baseline, suburban, urban, in traffic, upper atmosphere
 * candle flame, kerosene lantern flame, natural gas burner flames
 * internal combustion exhaust: before and after catalytic converter, diesel

"Several natural sources of CO of both biological origins have also been identified but their contributions to urban atmospheric concentrations are thought to be small. Background levels of CO (resulting from natural and technological sources) found in relatively unpolluted air range from 0.025 to 1.0 ppm. Urban carbon monoxide is produced primarily by motor vehicles.

Because motor vehicle traffic is the major source of CO, daily concentration peaks coincide with morning and evening rush hours. The worst carbon monoxide problems are found where large numbers of slow moving cars congregate. These problems are further aggravated when they occur in a "street canyon" situation. When there are large amounts of slow moving traffic in a street canyon situation, with the wind blowing perpendicular to the street, carbon monoxide can be trapped in the canyon and build up to unhealthful levels.

CO problems are usually worse in winter because: 1) cold weather makes motor vehicles run dirtier and requires more combustion for space heating; and 2) on winter nights a strong inversion layer develops in the atmosphere, that traps pollution near the ground, preventing it from mixing with cleaner air above."

"No standards for CO have been agreed upon for indoor air. The U.S. National Ambient Air Quality Standards for outdoor air are 9 ppm (40,000 micrograms per meter cubed) for 8 hours, and 35 ppm for 1 hour." "Average levels in homes without gas stoves vary from 0.5 to 5 parts per million (ppm). Levels near properly adjusted gas stoves are often 5 to 15 ppm and those near poorly adjusted stoves may be 30 ppm or higher."

"undiluted cigarette smoke contains about 30,000 ppm of CO, undiluted warm car exhaust about 7,000 ppm, and the chimney of a home wood fire about 5,000 ppm. Clean countryside air contains about 0.02 ppm of CO. The smoke from one pack of cigarettes, if distributed uniformly throughout an average sized house, could result in a CO concentration of up to 14 ppm.

An average healthy person at sea level is just barely affected by prolonged exposure to concentrations of 9 ppm, but the presence of other pollutants aggravates the situation, and respiratory and cardiac problems pose an increased risk. Chronic exposure to high concentrations of CO (30 to 100 ppm), such as in a poorly vented garage, can lead to long-term deterioration of the cardiovascular system." (1983) -69.87.199.142 01:12, 24 August 2007 (UTC)

Fair use rationale for Image:Chp co ligand.jpg
Image:Chp co ligand.jpg is being used on this article. I notice the image page specifies that the image is being used under fair use but there is no explanation or rationale as to why its use in this Wikipedia article constitutes fair use. In addition to the boilerplate fair use template, you must also write out on the image description page a specific explanation or rationale for why using this image in each article is consistent with fair use.

Please go to the image description page and edit it to include a fair use rationale. Using one of the templates at Fair use rationale guideline is an easy way to insure that your image is in compliance with Wikipedia policy, but remember that you must complete the template. Do not simply insert a blank template on an image page.

If there is other fair use media, consider checking that you have specified the fair use rationale on the other images used on this page. Note that any fair use images uploaded after 4 May, 2006, and lacking such an explanation will be deleted one week after they have been uploaded, as described on criteria for speedy deletion. If you have any questions please ask them at the Media copyright questions page. Thank you.

BetacommandBot 22:58, 29 October 2007 (UTC)

Mond process?
"Nickel carbonyl decomposes readily back to Ni and CO upon contact with hot surfaces, and this method was once used for the industrial purification of nickel in the Mond process.[5]"

To the best of my knowledge, this is still the only way nickel is purified to this day. If anyone knows differently please comment. Keith Henson (talk) 15:41, 27 August 2008 (UTC)

Other Names
I just noted that under the other names section there was only Carbonic oxide, adding the stock name might also be a good idea, I've seen it for other compounds on Wikipedia. 12.206.59.238 (talk) 03:04, 9 September 2008 (UTC)

NPOV
I have added an NPOV dispute to the "Carbon Monoxide in the Enviornment" section, because of its lack of citation and anti-global warming standpoint.

Please correct by adding non-bias citations. 71.184.255.196 (talk) 01:04, 30 October 2008 (UTC)

Disagree
C'mon. Really. Two things: (1) Is it NPOV to be anti-global warming? Is it then NPOV to be pro-global warming? The NPOV thing is to be NPOV to global warming, me thinks. But what do I know, I'm just a doctor in Earth Sciences. Second, (2) the text is not anti-global warming in my humble opinion, it is in fact NPOV. I don't hate religion, but I hate when a scientific hypothesis such as global warming is made into religion. It hurts us all, and most of all it hurts science. But what do I know. PS. I replaced the NPOV tag with a citation tag.Lindorm (talk) 15:40, 4 December 2008 (UTC)

It's not a "hypothesis", it has been conclusively proven. Stonemason89 (talk) 23:36, 22 February 2009 (UTC)

Reducing agent
As far as I know carbon monoxide is a very strong reducing agent, should this not be mentioned in the article? 196.207.33.197 (talk) 13:20, 20 January 2009 (UTC)

Is carobnmonoxide heavier than air or lighter than air? —Preceding unsigned comment added by 70.94.239.197 (talk) 17:32, 30 January 2009 (UTC)

About the same as air. Its molar mass is very close to that of nitrogen; hence, its density is roughtly equal to that of N2 as well. —Preceding unsigned comment added by Stonemason89 (talk • contribs) 17:09, 1 March 2009 (UTC)

Other Names, Part II
Does anyone see a reason why we should not add "oxygen monocarbide" as an alternative name? Because the carbon atom carries a negative electric dipole charge in this molecule, an argument can be made that the oxygen is actually reducing the carbon in this compound, not oxidizing it.

There's quite a bit of arbitrary-ness when determining formal oxidation states for compounds like these, but an argument could also be made that the carbon is in a -4 oxidation state and the oxygen is in a +4. The oxygen page does not list +4 as a possible oxidation state but it's not entirely unreasonable to do so, given that the other chalcogens (not to mention nitrogen!) can adopt +4 states with ease. Of course I would want to get feedback before making a potential controversial addition like adding +4 as a possible oxidation state on the oxygen page, or adding "oxygen monocarbide" as an alternative name here.

Alternatively, if one assumes that the dative covalent bond in the structure diagram is an oxygen-positive ionic bond of order 2, and that the two "standard" covalent bonds are both oxygen-negative, then this means that both atoms are zerovalent in this compound! I'm not sure if any one of these is the "right" answer; they are all correct to a degree, I suppose.

Stonemason89 (talk) 23:36, 22 February 2009 (UTC)

Haemoglobin affinity
Can someone explain exactly why carbon monoxide has a higher affinity for haemoglobin than oxygen. It's rather difficult to find a reason in textbooks, and I haven't found any explanation on wikipedia. Thanks in advance. --Miczilla (talk) 07:34, 28 April 2009 (UTC)

Molecular Properties
The statement concerning the HOMO being closer in energy to carbon's p orbitals resulting in a negative dipole moment on the carbon atom seems to directly conflict with EVERY molecular orbital diagram I have ever seen of CO. I suggest that this statement be removed unless it is properly referenced. -- R Green. University of Edinburgh, Chem 3 Student. —Preceding unsigned comment added by 188.220.32.32 (talk) 22:55, 8 November 2009 (UTC)

SMILES
Shouldn't the SMILES specification match the structure in the picture, and thus be [C]#[O]?

109.250.181.111 (talk) 10:19, 19 February 2010 (UTC)

CO in tobacco smoke
The prior version of the article was phrased to suggest that workplace smoking could generate dangerous levels of CO pollution. I have thus deleted the material in question. Anyone please discuss if you feel this is unwarranted. FellGleaming (talk) 23:14, 1 April 2010 (UTC)

Is CO an anhydride of formic acid?
For the edit of 20:58, 2 May 2010, the summary reads: 'Here's one where no citation is needed, as HCOOH minus H20 = CO. It's true by definition of the word "anhydride"'.

But the problem is that CO does not actually react with H2O to give HCOOH. The word "anhydride" is defined to require an actual reaction, as in acidic anhydride which says "An acidic oxide (sometimes known as an acidic anhydride ...) is an oxide that either reacts with water to form an acid; or reacts with a base to form a salt." Or as in Petrucci et al "General Chemistry" (8th edn p.274) which is more restrictive and defines "An acid anhydride is a nonmetallic oxide that reacts with water to produce a ternary acid as the sole product."

CO does not qualify since its reaction with water is the water-gas shift reaction which forms CO2 and H2. That is presumably why a citation was requested. I think we should remove the statement that CO is an anhydride of formic acid. Dirac66 (talk) 22:23, 5 May 2010 (UTC)


 * I agree. The edit summary itself seems to indicate that this is merely unfounded extrapolation, rather than a statement with any real insight or value.&mdash;Tetracube (talk) 22:37, 5 May 2010 (UTC)


 * It's not that CO reacts with water to give formic acid. It's that when formic acid is stripped of water by concentrated sulfuric acid, CO is formed. It's a standard way of making the stuff. Thus, carbon monoxide is the anhydride of formic acid in the same sense that phosphoric anhydride (phosphorus pentoxide) is the anhydride of phosphoric acid. Not all anhydrides can be reconstituted with water. Here is example of one that cannot.  S  B Harris 03:27, 6 May 2010 (UTC)


 * Yes, you are right. I had forgotten to consider the reverse reaction. I see now that this dehydration is already mentioned as the first example in the section Laboratory preparation. Perhaps the article on Acidic oxide needs a third clause "or is produced by dehydration of an acid". Dirac66 (talk) 13:26, 6 May 2010 (UTC)


 * So what you are saying is that nitrous oxide should be considered the anhydride of hyponitrous acid? That seems a bit preposterous to me.&mdash;Tetracube (talk) 19:30, 26 May 2010 (UTC)

"Concentrations as low as 667 ppm"
The article currently claims "Concentrations as low as 667 ppm may cause up to 50% of the body's hemoglobin to convert to carboxyhemoglobin"

In the research paper cited, according to the abstract, in each experiment, the subjects were first exposed to 3,000 ppm of CO, and then exposed for intermittent periods to a range of exposures from 3,000 ppm CO to 667 ppm CO. — Preceding unsigned comment added by Undomelin (talk • contribs) 23:18, 17 November 2010

'Resonance'
.. and can be represented by three resonance structures:..


 * [[Image:Carbon Monoxide(png).svg|300px]]
 * Really?? The second and third 'resonance' structures do not have octets on the carbon. Shouldn't the article discuss that?

Jcwf (talk) 04:39, 11 October 2008 (UTC)


 * This, like O2, is a case where diagrams like this do not really work and molecular orbital theory has to be used. --Vuo (talk) 19:41, 20 January 2009 (UTC)


 * O2 is a special case because experiment shows that the ground state is a triplet with two unpaired electrons, so any structure with only electron pairs is inadequate. However CO has a normal singlet ground state, so the :O≡C: structure is perfectly adequate for a simple description of the molecule. The non-octet structures are of negligible importance except in high-precision quantum-chemical computations. I think they should be removed from the article, but I will start by requesting a source for the statement that three resonance structures are needed. Dirac66 (talk) 01:37, 14 July 2010 (UTC)

Why CO is lighter than air.
Every few weeks someone changes "lighter than air" to "heavier than air", usually changed back after a few hours or days. So here is the reasoning at a first-year chemistry level: From the ideal gas law, gas density is proportional to molar mass M (molecular weight). For CO, M = 28.0. Air is about 80% N2 (M = 28.0) and 20% O2 (M = 32.0), so the average M is 28.8. Therefore the answer is that CO (M = 28.0) is slightly (3%) LIGHTER than air (M = 28.8). Dirac66 (talk) 19:12, 20 July 2010 (UTC)
 * Exactly. In ideal gases, each molecule (no matter what kind, or how heavy) takes up the same "volume" in the gas. So ideal gas densities are exactly proportional to molecular weights. CO molecules are slightly less heavy than air (since they are about as heavy as N2), so CO is slightly less dense than air at the same temp. Not enough to make much bulk difference in behavior (like climbing toward the ceiling). Any behavior like that is due to the fact that CO is usually generated at temperatures that are higher than ambient, so it's less dense because it's warm. S  B Harris 02:16, 8 December 2010 (UTC)

Astrophysics
Carbon monoxide is the second most common molecule in the universe (after molecular hydrogen), and its emission can be detected across cosmological distances. The role of CO in astrophysics should be included in this article. (Yes, I know, I should do it myself, and I will when and if I can find the time. Meanwhile, this will at least remind me if not others to work on it.) Mordecai-Mark Mac Low (talk) 05:20, 23 December 2010 (UTC)

Another use
Where I come from, executions are done by injection of carbon monoxide, dissolved in some solvent. It was chosen for being painless, fairly rapid, and tidy. Could this also be listed under "Uses"? —Preceding unsigned comment added by 70.27.125.66 (talk) 07:01, 16 January 2011 (UTC)
 * Can you add a reliable reference for this fact? Materialscientist (talk) 07:04, 16 January 2011 (UTC)
 * Only if you can verify the information with a citation from a reliable source. --&mdash;Elipongo (Talk contribs) 07:09, 16 January 2011 (UTC)
 * says that it was used by Romans and Greeks. I wait for Plato, Socrates and Plinius for further edits.--Stone (talk) 07:31, 16 January 2011 (UTC)
 * Presumably some Greeks or Romans had observed the toxic effects of incomplete combustion with inadequate ventilation, of course without any idea that this involves a gas compound of carbon and oxygen. But I think we need a reference to a modern use in which the nature of CO is understood. Dirac66 (talk) 17:11, 16 January 2011 (UTC)

Dipole moment
Is my hypothesis correct that the dipole of CO is determined by the charge of the nucleus: less protons = surplus negative charge?--Wickey-nl (talk) 17:25, 10 February 2011 (UTC)
 * The dipole of any molecule is determined by both proton charges localized on nuclei and electron charges distributed in molecular orbitals. The dipole of CO is very small due to a delicate balance of effects, and is therefore very hard to either measure or calculate. As I recall from the 1960s and 1970s, it seemed that every new measurement and every new calculation reversed the sign when smaller and smaller corrections were applied. It took several years before the polarity C- O+ was definitely confirmed. For purposes of Wikipedia this means that any brief explanation is too simple. Dirac66 (talk) 03:52, 11 February 2011 (UTC)


 * Do you agree with this explanation (first page)? Simple and adequate?--Wickey-nl (talk) 15:21, 11 February 2011 (UTC)


 * Yes, this link gives a good simple explanation of why the dipole is close to zero. We can then add the simple statement that very accurate experiments as well as calculations have shown that carbon is the negative end. A possible reference is I.N.Levine "Quantum Chemistry" (4th edn Prentice-Hall 1991, p.414-415), which cites the calculation by S.Green, J.Chem.Phys. 54, 827 (1971). Dirac66 (talk) 15:45, 11 February 2011 (UTC)

If weak σ-donor co‐ligands (= other ligands) or a cationic complex → enhanced CO‐to‐metal σ electron transfer → O+; if strong σ-donor co‐ligands or an anionic complex → enhanced back donation to O → O-.
 * The given link, page 5, also makes clear that the resonance structure is useful for CO-ligands. See the Dewar-Chatt-Duncanson model:


 * It also shows, why the image with the suggested bond length in the chembox (with a false source!) is arbitrary and undesirable. --Wickey-nl (talk) 12:15, 12 February 2011 (UTC)
 * Unfortunately, we cannot be sure if that link will exist in the future.--Wickey-nl (talk) 12:23, 12 February 2011 (UTC)

CO is isoelectronic with N2, and the shortness and strength of the CO bond (it's even shorter and stronger than N2) leaves no doubt that the electron configuration in terms of molecular orbitals is the same in CO as in N2. Thus, there are no electrons in pi*-antibonding orbitals. The bonding orbitals sigma and 2 pi's, are filled, giving a bond order of 3, with a lone pair of electrons on each atom. The closest to showing this correctly is with a triple bond. Now, ordinarily, this would confer a positive charge on O and a negative charge on C. You can think of it as N2 with the exact same electron cloud, and movement of a nuclear proton from one atom to the other (forget the neutrons), which would give exactly that charge distribution. But due to this charge movement, these bonding electrons in their 3 bonding orbitals are able to "slosh" toward the oxygen to almost entirely cancel its + charge, and still remain bonding electrons. So these three bonds with 6 electrons are all polar by about 1/6th, and that transfers nearly one net charge from C --> 0, without making a triple into a double bond. The only way to make double bond in CO by hybriding atomic orbitals would be a sp2 hybridized ..C=O:: carbon as in formaldehyde, but without the neutral hydrogen atoms, so that there would be two free radical electrons in sp2's, both on the carbon (in lobes where the hydrogens go in H2CO). That's not stable. The triple bonded sp structure isoelectronic with N2, CN- and carbide/acetylide

-:CC:-

demands triple bond and a lone pair on each atom, so that has to happen. The only way to move charge from one end of the molecule (as compared with N2) and still leave a lone sp electron pair lobe on each atom, is to polarize all three interatomic bonds. And apparently, that happens so well, as to nearly make up for the "movement" of the proton, by comparison with N2. S B Harris 00:38, 13 February 2011 (UTC)

Furthermore your (nice) explanation holds for the free molecule, not for the metal carbonyl.--Wickey-nl (talk) 13:49, 13 February 2011 (UTC)
 * I don't know if you can say there is no electron density in pi*-antibonding orbitals at all, but you can say the Lewis structure with three bonds does not picture the polarization. In that respect that Lewis structure fails. Why should carbon be a diradical if two bonds and not have a simple shift of electrons to oxygen to form an extra lone pair?

Anoxemia
I removed the statement, already marked as needing citation, which implied that anoxemia is the same thing as carboxyhemoglobin production. Multiple dictionaries state that anoxemia is simply lack of oxygen in the blood, without any particular cause. It remains possible that the result of carboxyhemoglobin production might be called anoxemia, but it's clear that they are not synonymous, as the wording implied. In addition, anoxemia appears to be an outdated term and so even if introduced, should be given as an historical term. Paleolith (talk) 16:10, 5 March 2011 (UTC)

Reply to Plasmic Physics' edit summary
Reply to the edit summary of Plasmic Physics who reverted my edit today.
 * Yes, "One" indicates there is another C-O bond, in fact two others. A triple bond may also be described as three bonds between the same pair of atoms, each corresponding to the sharing of one pair of electrons. In this case only one of the three bonds is dipolar (or coordinate) as the shared electrons are both from O. The other two bonds each involve one electron from C and one from O so they are normal covalent bonds.
 * 1) "on the oxygens end" is not English. The possessive would be "on the oxygen's end" which I did not write. I wrote "on the oxygen end" which does indicate that O is the end. Dirac66 (talk) 01:59, 27 March 2011 (UTC)


 * In that case, it should be called a molecular orbital, otherwise it's confusing. I didn't see that you removed the "s", I thought you added it. Plasmic Physics (talk) 03:03, 27 March 2011 (UTC)

Odd figure
Someone recently added this figure to the article. No doubt their intentions are good, but I think the figure is hard to understand and at times wrong, and ultimately the article is better off without it. For example, what do the little green numbers in circles above the molecules signify? The figure also mixes molecular orbitals with atomic orbitals, and presumably having the 3 MOs off center in CO is supposed to symbolize something. Furthermore, with C∞v symmetry, the two π-bonging MOs of CO should be at the same energy level. And it's unclear from this representation whether those MOs are populated. Etc. Lots of problems. If we want to illustrate the electronic structure of CO and it's dipole moment with a figure, I'd suggest instead using a MO diagram to illustrate the electronic structure and an electron density map to illustrate the dipole moment. Yilloslime T C  22:52, 29 March 2011 (UTC)
 * Since no one disagrees, I've removed the figure. Yilloslime T C  19:23, 30 March 2011 (UTC)

Executions in antiquity
I have removed this claim, from the article. It seems highly dubious to me and the sourcing is not good. The article source (a medical paper not historical) sources it to the book Ganong, Review of Medical Physiology 1995, p.695. I have not seen the 1995 edition, but google books snippet seems to verify the claim is there. However, it is no longer in the 2005 (22nd) edition and one can only assume it was removed for good reason.  Spinning Spark  12:57, 22 October 2011 (UTC)
 * The gas was used for executions by the Greek and Romans in Classical Antiquity,[7]


 * I agree, it does seem poorly sourced and unlikely. Also, even if the Greeks or Romans did suffocate people with smoke, they certainly didn't know about CO, and other poisoning and oxygen-deprivation methods would have played a part in such a method. Squiddy | (squirt ink?)  13:52, 22 October 2011 (UTC)


 * Yes, exactly, although I have now found some more sensible sources on this and may write a new draft shortly. Meanwhile, I am also taking out:


 * Carbon monoxide has been used by humans since prehistoric times, for the smelting of iron and other metallic ores.[6] It first described by the Spanish doctor Arnaldus de Villa Nova in the 11th century.[7]
 * Carbon monoxide was not isolated or identified by de Villanova. He merely noted that unventilated wood fires were toxic.  Since this was already known from ancient times he could not have even been the first for this much.  Prehistoric iron smelting is in much the same vein - yes carbon monoxide is involved in the process but highly unlikely that anyone understood that there was a gaseous agent at work.   Spinning  Spark  17:01, 22 October 2011 (UTC)


 * I am replacing it with the following more authoritavely sourced passage. I will also try to work back in the relation to iron smelting in a more appropriate way. Comments?  Spinning  Spark  18:23, 22 October 2011 (UTC)


 * That burning coals emanated toxic fumes was first recorded by Aristotle (384-322 BC). An ancient method of execution was to shut the criminal in a bathing room with smouldering coals.  What was not known was the mechanism of death.  Galen (129-199 AD) speculated that there was a change in the composition of the air which caused harm when inhaled.
 * Yes, I agree that we should not say that CO was "used" before it was shown to exist in 1800. It may have caused deaths in ancient executions, but no one knew then that CO was a factor so it was not a conscious use. This subject has been discussed briefly on this talk page - see (Talk:Carbon monoxide/Archive 1. Dirac66 (talk) 18:55, 22 October 2011 (UTC)

Astrophysics
Carbon monoxide is the second most common molecule in the universe (after molecular hydrogen), and its emission can be detected across cosmological distances. The role of CO in astrophysics should be included in this article. (Yes, I know, I should do it myself, and I will when and if I can find the time. Meanwhile, this will at least remind me if not others to work on it.) Mordecai-Mark Mac Low (talk) 05:20, 23 December 2010 (UTC)


 * I took a crack at it. Could use improvement, but it's a start. diff —Alex (ASHill &#124; talk &#124; contribs) 23:17, 21 January 2012 (UTC)

Added line
Added this, don't remove, find extra sources if possible CO can also be produced from CO2, by treating this latter gas with microwave radiation. This was a popular method in nuclear submarines as they needed to get rid of the CO2 gas without leaving a bubble trail. This method is now being re-examined by Waldo Bongers of the Dutch Institute For Fundamental Energy Research.

91.182.177.243 (talk) 13:19, 15 July 2012 (UTC)

Copyright Violation?
Much of this article overlaps with http://www.jjstech.com/carbonmonoxide2.html. Which came first?

192.249.47.201 (talk) 17:48, 30 July 2012 (UTC)


 * Probably WP came first. You can search the history for when various parts were added if you're uncertain, and see if the WP version "evolved" to what the jjstech site has.  In general, you'll find many such wiki copies, often lacking the required attribution.  Dicklyon (talk) 19:00, 30 July 2012 (UTC)


 * The lead evolved to look like the one in that mirror site in the middle of 2008. So it's OK.  Dicklyon (talk) 19:06, 30 July 2012 (UTC)

Reverted vandalism 10/7/12
I have undid the revisions by the editor 2A01:E35:2E51:D5B0:29D7:7E9D:A760:E109 on 00:13, 7 October 2012 and 00:12, 7 October 2012. The edit added unnecessary material and I have evidence that the edit was made maliciously in order for the Editor to make the following post on a different website. http://www.rationalskepticism.org/pseudoscience/expanding-earth-do-the-continents-wind-back-to-a-sphere-t8539-6560.html#p1495530 As such I take the Edits as vandalism and have reverted them.Donhoraldo (talk) 17:19, 7 October 2012 (UTC)


 * The Editor has used a sock puppet to undo the reversion. The reversion has been undone as this is in discussion here.


 * The original Statement that "Carbon monoxide". . ."combines with oxygen to form carbon dioxide and ozone" is true. The carbon monoxide absorbs an oxygen atom and the reaction leads to a Ozone molecule being produced. There is no reason to clutter the first paragraph with more detail. The main body of the article already covers the process by which this happens.
 * No, it is chemically incorrect to write that carbon monoxide combines with oxygen to form carbon dioxide and ozone, and for many reasons. The first one is that CO does not combine with oxygen (O2) but with hydroxyl radical (•OH). Evidently •OH must not be confused with "an atom of oxygen". Secondly, the reaction of CO with •OH forms a radical intermediate •HOCO. This species is short-lived and transfers rapidly its radical hydrogen to O2 to form peroxy radical HO2• and CO2. No ozone is formed at this point.  Ozone is formed later by another sequence of reaction starting with the peroxy radical and involving NO. In Reeves et al, it is clearly written "However OH reacts primarily with carbon monoxide (CO) and hydrocarbons to produce peroxy radicals (HO2 and RO2), which can react with nitric oxide (NO) [to form NO2]." Then a few lines later " reactions (6) [HO2• + NO → NO2 + •OH] and (7) produce nitrogen dioxide (NO2), which via photolysis gives O(3P), thereby forming O3 following reaction with O2..". Clearly, the revision reverted by Donhoraldo was correct while the original sentence is wrong. If the general consensus is that the revised sentence is too much detailed for the introduction, I propose to move it to the body and use a simpler but correct version in the introduction   (Florian N (talk) 20:39, 8 October 2012 (UTC))
 * It would certainly be useful to include the reactions described by Florian N in the section on ground-level ozone, with perhaps a link to the discussion at Tropospheric ozone. For the introduction I would limit the material on ozone to one sentence, perhaps just to say that CO has a role in the formation of ground-level ozone without further detail. Dirac66 (talk) 21:40, 8 October 2012 (UTC)
 * Agree. Good idea to give a description of hν. It is apparently not obvious that it is the way to represent photons in chemical reactions, as shown by the flawed reversion by Donhoraldo.(Florian N (talk) 21:08, 10 October 2012 (UTC))
 * Also on a personal level I resent the fact that the editor claims I am motivated by a bias.Donhoraldo (talk) 20:53, 7 October 2012 (UTC)


 * First of all you need to stop edit warring in the article right now. Opening a discussion here does not give you the right to keep reverting the article to your favourite version.  You also need to stop with the accusations: addition of cited text does not fit our definition of vandalism, change of IP does not constitute sock puppetry, and saying the same thing as on another site is not disruptive (or even relevant).  What we need to concentrate on is the actual content of the article, and if you want to remove peer-reviewed referenced material it is really incumbent on you to show that the ref is not appropriate and provide a better one.
 * I do agree that details of the reaction would be better in the body of the article. So why not move them there instead of deleting, especially as a high-quality reference has been provided.  Spinning  Spark  21:28, 7 October 2012 (UTC)
 * Because the material is in the article already. As I pointed out in my previous post the material is covered in the section, Role in ground level ozone formation. Further the section already references an article not behind a pay wall.Donhoraldo (talk) 22:51, 7 October 2012 (UTC)
 * Oh and as a Note I was within the 3RR. I wasn't aware that a Edit war had began until that is broken.Donhoraldo (talk) 22:57, 7 October 2012 (UTC)
 * If the question is about the ref then I just added it to the section were it belongs.Donhoraldo (talk) 23:08, 7 October 2012 (UTC)
 * I have replied on your talk page.  Spinning Spark  23:23, 7 October 2012 (UTC)
 * My talk page is blank?Donhoraldo (talk) 23:27, 7 October 2012 (UTC)
 * Got it now. I would note that as I said before I was withing the 3RR and was following BRD. I just felt that a poorly written re-wright of a well written section in order for a person to use WIKI to win an argument counted as vandalism.Donhoraldo (talk) 23:38, 7 October 2012 (UTC)
 * I am taking this to your talk page as this is more about yoru behaviour than this article.  Spinning Spark  09:58, 8 October 2012 (UTC)
 * Given the party in question has again changed the material drastically without discussing it might you take note of that? Dispite the referances he has again changed the article to be inline with the forum post I linked above. This isn't meant as an ad hom. This is simply what I'm seeing.Donhoraldo (talk) 01:06, 9 October 2012 (UTC)
 * It is under discussion above, Dirac66 suggested putting it in there to Florian N. Do you disagree that the reaction is correct? Because if not, there really is not a problem.  If you do disagree, is the reference supplied by Florian reliable?  Spinning  Spark  01:50, 9 October 2012 (UTC)
 * Here is a book source that is not behind a paywall and seems to support Florian's model.  Spinning Spark  02:04, 9 October 2012 (UTC)

Sign of charge still confused?
To DMacks: Your latest edit changed from "Oxygen has more electron density, but also more positive charge. Because most electron density is located between the atoms, the molecule has a net positive charge on the oxygen end." to "The molecule is therefore asymmetric: oxygen has more electron density than carbon, and is also slightly negatively charged compared to carbon being positive." I agree that the density between the atoms should not be mentioned here, but why have you changed the net charge on oxygen to negative? The previous paragraph explains that it is positive because the dative bond outweighs the electronegativity difference in the other two bonds. Dirac66 (talk) 13:21, 21 May 2013 (UTC)
 * Because I'm an idiot? Yup, I screwed up the charge:( DMacks (talk) 15:24, 21 May 2013 (UTC)

Assessment comment
Substituted at 14:27, 1 May 2016 (UTC)

Heat of Boudouard reaction
Today editor 14.139.245.2 changed the value of ΔH for the reaction CO2 + C → 2 CO from -221 kJ/mol to +170 kJ/mol, which was reverted two hours later by Drbogdan. However I have checked the data tables in P.W.Atkins and J.de Paula, Atkins' Physical Chemistry (8th ed., W.H.Freeman 2006), p.996. The heats of formation ΔfH0 are -110.53 kJ/mol for CO and -393.51 for CO2. So ΔH = (2 x -110.53) - (-393.51) = +172.45, probably best rounded off to +170 to allow for temperature variation, and the numbered editor was right this time. To obtain -221 one must forget to subtract ΔH for the reactant. I will fix it again. Dirac66 (talk) 21:46, 16 March 2014 (UTC)

External links modified
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Recent review
Of signalling properties 10.1152/ajpcell.00360.2016 JFW &#124; T@lk  20:54, 14 November 2017 (UTC)

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 * first two are good, third is incomplete. Graeme Bartlett (talk) 23:35, 21 January 2018 (UTC)
 * Third is externa link without explanation, so removed. Graeme Bartlett (talk) 23:39, 21 January 2018 (UTC)

Strongest Bond
The article describes CO represents the strongest known chemical bond. Can RFB≡O and RFC≡O+ be stronger? Anoop Manakkalath (talk) 18:00, 3 April 2020 (UTC)
 * Our article at Oxoborane does not mention any bond dissociation energies, and I do not see any in the free-text portions of the sources cited. VQuakr (talk) 20:35, 3 April 2020 (UTC)

कार्बन मोनोऑक्साइड, कार्बोनेट ऑक्साइड
Mr.manglesh chouhan (talk) 11:41, 16 March 2021 (UTC)


 * I am removing your Hindi version of the article. It would be better to write at hi:कार्बन मोनोआक्साइड, as this here is English Wikipedia. Graeme Bartlett (talk) 12:03, 16 March 2021 (UTC)

Thermochemical data
It may be pointed that the carbon dioxide article gives its heat of formation as -393.5 kJ/mol but that the sum of heat of formation (-110.5 kJ/mol) and heat of combustion (-283.4 kJ/mol) given in this article is -393.9 kJ/mol. Is this due to some inconsistency or because some type of correction needs to be applied before calculating the CO2 heat of formation from the CO data?150.227.15.253 (talk) 14:09, 22 April 2022 (UTC)


 * Thank you for pointing out this inconsistency. I have now verified that the two heats of formation (for CO and CO2) agree with the NIST Chemistry Webbook which is listed as one of the Infobox references, except that the values have been rounded to the nearest 0.1 kJ/mol. For consistency the heat of combustion should be the difference of the two heats of formation which is -283.0 kJ/mol, although NIST only gives heats of formation explicitly. In fact this article has a See also section including Carbon monoxide (data page), which already has -283.0 for the heat of combustion. So I will now change the infobox value to -283.0 also to be consistent with the NIST values. Dirac66 (talk) 14:34, 16 May 2022 (UTC)