Talk:Benzene/Archive 1

Archive 1

Miscellany

It would make sense to have the IUPAC name as well as the trivial 'Benzene' listed on this page, either in the fact box or on the top description. I can advise now that it is Cyclohexa-1,3,5-triene. Thanks. —Preceding unsigned comment added by Fragmaster (talk • contribs) 16:42, 29 September 2008 (UTC)

Perhaps all the discussion of aromaticity and delocalisation should be moved to aromatic? Iridium77 16:17, 21 Feb 2004 (UTC)

I tend to agree with the above suggestion that the discussion of aromaticity and delocalisation should be at least partially simplified and/or moved to aromatic. Also, there is no mention of a BTX plant in which benzene is involved. H Padleckas 08:22, 23 October 2005 (UTC)

How to make benzene from reformate

In the paragraph about catalytic reforming it says that "The aromatic products... are then separated... by extraction with... solvents". The solvents mentioned refer to liquid-liquid extraction, which is a still used. Chemical plants more and more use extractive distillation, which uses solvents such as NMP (N-Methyl-Pyrollidon), NFM (N-Formyl-Morpholine) or Sulfolane. For reference, please take a look into Arpe, Weissermel: "Industrielle organische Chemie" (sorry, it's a German book), the "Ullmann's encyclopedia of industrial chemistry" (article "benzene") or the "process handbook" of "Hydrocarbon processing" Camedpr (talk) 16:16, 24 November 2008 (UTC)

Production routes to benzene

I have read, that predominantly in China benzene is again produced from coke oven light oil. China uses its coal to produce coke. As a secondary product coke oven light oil with a very high content of aromatics is produced. The benzene is produced via extractive distillation. Camedpr (talk) 16:16, 24 November 2008 (UTC)

Is benzene REALLY metabolized ?

"In the body, benzene is metabolized. " Actually, my academic teacher (Ph.D. in organic chemistry) said that it is not! He said that it intercalates with DNA and leads to its mutations (or sth like that).

graduate student at the Wroclaw Univ. of Thechn.

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A brief google search for benzene metabolism would like to dispute that claim. See [1]

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—Preceding unsigned comment added by 202.156.8.10 (talk) 13:43, 24 September 2008 (UTC)

Photo Error

The "projection" view of benzene intended to demonstrate the position of the p-orbitals is pretty good, but the benzene line drawing that the orbitals are overlayed on is missing one of its double bonds. Only two Pi bonds are shown, there should be three. Alternatively, the lines signifying Pi bonds may be eliminated and replaced with a circle in order to emphasize the aromaticity of benzene.

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Hey I'm not to confident in how to use the editing functions etc so thought I'd leave this up to someone with the know how...

On the Reactions of Benzene[2] site it incorrectly states that one of the reagents of an acylating freidal-craft's reaction is water. This is a major error as any reaction using Aluminium Chloride must be changed to anhydrous lest a young chemist lose their eyebrows attempting such a reaction. I myself being a young chemist just about to take my A-Levels would appreciate this to be rectified as soon as possible as I doubt I am the only student using this website for revision. I would however like to show my appreciation to all contributors of this site as it is a great help

Many thanks! Jon

If you are referring to this image, I don't think there is a mistake. The reaction itself is done under anhydrous conditions. But the addition of water is a second step to "quench" the reaction once it is complete. This of course needs to be done carefully because it will be quite an exothermic reaction. --Ed (Edgar181) 12:32, 10 April 2006 (UTC)

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I was thinking that for the box on the right of the basic information of Benzene, the first structural picture should be replaced with the first picture in the section about structure in the main article. I feel otherwise people may not see that there are actually Carbon atoms on every corner. What do yo guys think? Jon *not the same from above* Jfspinner88 (talk) 22:06, 13 October 2008 (UTC)

External Yale links

I've removed these two external links

• Couper and Carbon bonds

• Kekule, Couper and dreams of Benzene

because they appear to be blocked to people outside of Yale University. Someone who can see the Yale pages, may want to summarise them, or link to some equivalent pages elsewhere.

-- I can see these pages from this computer (proxad.net, Paris France). If I'm not the only one we may put them back. I've noticed too that the toxicology is mostly a copy of http://www.atsdr.cdc.gov/tfacts3.html but I don't know the copyright status of this document. MrPhelps 18:16, 4 August 2005 (UTC)

I can see them just fine. I don't know if something has changed in the last year or not, but I thought they were worth adding again anyway if at least a few people can see them. - Taxman ^Talk 19:27, August 4, 2005 (UTC)

Main image

I notice the main image, Image:Benzene structure.png, contains two representations showing the outdated and incorrect Kekulé structure (ie. those with double bonds). Benzene contains no double bonds (which have a bondlength of 0.13 nm) and is not totally single bond (0.15 nm)but has delocalised electrons inducing a bond length of 0.14 nm. --Oldak Quill 18:57, 14 Apr 2005 (UTC)

Good point. But what you call "outdated and incorrect Kekulé structur" is just the most common way to draw benzene rings and other aromatics. It has important advantages to do it this way (you can easily see how many electrons you actually have) and does not at all imply missing aromaticity. Additionally, the aromaticity in explained in-depth in the article (including equivalent bonds). Cacycle 20:48, 14 Apr 2005 (UTC)

I like the representations with the circle inside the hexagon better and I've been using such representions for practically all of my aromatic structure images, but I concede that the three alternative double bond image seems to be the most commonly used for aromatics in various organic chemistry books I've looked at these days, although both representations are used.
H Padleckas 08:06, 23 October 2005 (UTC)

Two draw one of the two mesomeric structure is not the best way to do it but the circle in the middel confuses some people a lot. What does the oxygen stand for in the middle?

The two mesomeric structures which normaly are drawn represent contribute ca 20% of the sum of orbital interaction. The dewar benzen structure, where the orpitals of oposit corners overlap contribute 30% (because there are more different structures). So this should be the structures drawn in the mesomeric picture! (This is citation of a lecture derived from computational chemistry). Do not change the page because of this! But it is nice to remember the different view point even for benzene.Stone 14:42, 1 February 2006 (UTC)

This is the first I've heard about substantial electron density in the "center" of the π system...looks pretty suspicious with respect to symmetry. Who gave this lecture? DMacks 21:27, 28 February 2006 (UTC)

While I'm not suggesting any change in the article, I don't think there is any evidence the Kekulé structure is the more common structure. I've nearly always drawn it with the circle inside the hexagon and it was always the way I was taught to draw it and the way I've seen in most text books (if the other structure is presented, it's usually just showing it but mentions the other structure is preferred because it's considered more accurate or something). Perhaps the use of the Kekulé structure is an Americanism or something? Nil Einne 13:40, 10 March 2007 (UTC) Kekules structure isn't quite an ameircanism, when we are drawing reaction mechanisms, it is almost impossible to show where exactly the electron came from if there is a circle, when there are diffinative bonds and it is appretiated that they are conjugated it is best to draw a kekule structure, perhaps the article needs a section on resonance and aromatic stabilisation energy to show that the circle and the kekule structures are fundamentally the same and it depends what you sare trying to illustrate which one is best to draw? —Preceding unsigned comment added by 129.11.251.229 (talk) 23:48, 2 March 2009 (UTC)

Is it possible to have 6 carbons in a ring with no hydrogen and only double bonds?

Nice question, Richard Johnson presents a number of studies on small cyclic cumulenes here: [3], fascinating reading. Inclusion of such species should probably be limited to the Cumulene article, however. Eutactic (talk) 10:40, 16 September 2008 (UTC)

Carbon ring

Should carbon ring redirect here, as benzene is only one type of carbon ring, and is called a benzene ring. -- Kjkolb 04:35, 13 November 2005 (UTC)

• No, you're right, it shouldn't. I can't think what to do with it though. A disambig page? Physchim62 (talk) 09:08, 13 November 2005 (UTC)
  • I made it into an article as best I could, but some more knowledgeable should check it out and expand it. I don't understand why a disambiguation page would be needed, as benzene can be (and is) mentioned as one example of a carbon ring in the article. Is there something I'm missing? -- Kjkolb 09:16, 18 November 2005 (UTC)

Structure

"... and it is known that a single bond is longer than a double bond. In addition, the bond length, the distance between the two bonded atoms in benzene is less than a double bond, but longer than a single bond." These lines do not make sense. If a single bond is longer than a double bond, then how can the bond length in benzene be less than a double bond but more than a single bond? Should this read "less than a single bond, but longer than a double bond" instead?

The introductory paragraph on structure is obscure. What is it meant to say? What alternative structures were investigated and why were they unsatisfactory?

I know about Dewar benzene, Claus benzene, Ladenburg prismane and Benzvalene, I can draw their structures and write a little text about them and add it to the section. Any objections?--P D L 15:47, 4 April 2006 (UTC)

great stuff but these topics should really be in aromaticity or in a new article something like benzene isomers V8rik 22:29, 4 April 2006 (UTC)

I disagree. The structures of the aforementioned "benzenes" were hypothetic and only of historical significance. While most of them have been synthesised, they are unstable and rapidly isomerise to benzene.--P D L 15:47, 7 April 2006 (UTC)

Soft drinks

The paragraphs added about soft drinks ([4]) should be removed. First, they are written in a news report style and the investigation is still occuring. Second, the current investigation is unimportant relative to the numerous industrial and other uses of benzene. The topic should be mentioned, but there is far to much about this relativly minor topic on an article about a very important chemical. I will delete the section, add a sentense about the topic, and branch it of as a new article. Polonium 20:36, 10 April 2006 (UTC)

• try to convince the Wiki community as a whole that there is no place in Wiki for current events reporting, good luck!. It is reported, ongoing but definitely Wiki material provided references are included. Having said that I think that the bulk of the content on this topic should be in sodium benzoate, the benzene article will just have one sentence itself. Also: my source tells me an average person has to consume 20 liters of soft drink each day to make up for the amount that person already inhales from the air on a daily basis, is it possible to verify? V8rik 20:51, 10 April 2006 (UTC)

Merger

I am of the opinion that the section about resonance would be more appropriate at resonance (chemistry). Isopropyl 22:40, 10 April 2006 (UTC)

The resonance in benzene is really important (really, its dominant characteristic) as is the aromaticity related to the resonance. I don't think tbe content should be removed in benzene, although some information could be repeated at resonance. Olin

• the benzene article should be about benzene the chemical, properties, use etc. The resonance (chemistry) part should be in resonance, the aromaticity part is already covered in aromaticity and the long list of benzene derivatives should belong in Simple aromatic ring. The benzene article should be expanded with something about industrial production and some information about exactly why benzene is so harmfull. V8rik 17:01, 12 April 2006 (UTC)

• removed merge notice and trimmed down some of the structure part as aromaticity is already covered in aromaticity V8rik 22:09, 13 May 2006 (UTC)

Side note on benzene

Some soft drinks contain benzoate, which can react in your body to form benzene. Among these are Big 8 Sparkling Lemonade and most (if not all) cherry sodas. Among the brands and soft drinks that don't use benzoate are Crush, President's Choice Cola, and Pepsi. Also, there are a few that contain sodium benzoate, which some people think is just as toxic, but studies show that it's nearly harmless (except in amounts literally impossible for a human being to ingest in 10 hours, which by then it will have been disposed of), and it merely causes a bad aftertaste, which is the real reason why it isn't used in more than 0.1% concentrations. One of these is PC Orange. This is not a complete list. Please tell me if this should be in this article or in a benzoate article, or if this belongs in a benzoate talk page, and which one. Random the Scrambled 12:21, 1 May 2006 (UTC)

No it definitely doesn't belong here, this has been discussed before. Also, I've never heard of most of your brand names, perhaps they're only found in North America or something. Besides that, what your saying doesn't make much sense. Sodium benzoate is just the sodium salt of benzoate. I'm doubtful there is any difference in the toxicological profile of sodium benzoate compared to potassium benzoate or calcium benzoate Nil Einne 13:45, 10 March 2007 (UTC)

Detail - can benzene be pluralized?

The article, which is excellent, refers to substituted benzenes. This is as good a place as any to discuss this bit of English. For myself, I dont pluralize elements or compound names, but what do others think?--Smokefoot 04:58, 21 June 2006 (UTC)

Do you really never talk about "tertiary phosphines"? I would agree that it seems ugly to use "organotins" instead of "organotin compounds", but this sort of usage for derivatives of 'pure' organic compounds (particularly those containing ring structures) seems widespread and irreproachable. That's my two euro-cents worth, anyway! Physchim62 (talk) 12:52, 21 June 2006 (UTC)

I don't see anything wrong with benzenes, phosphines and similar plurals. However, as a section header, there's little need for the plural. How about changing it to Substituted benzene or Benzene derivatives? ··· rWd · Talk ··· 22:24, 23 June 2006 (UTC)

This kind of pesky question can prove pesky and are not important. But for the record, the arguments made above do not mention real cmpds. Sure, "tertiary phosphines" or "phosphines" but "triphenylphosphines"? Oh, well no big deal. I'll tweak the header and let others fight it out.--Smokefoot 22:36, 23 June 2006 (UTC)

Phosphine was a real compound last time I checked, thogh I agree that it is pesky, especially if inhaled ;) How about we go for "try to avoid pluralising compound names if possible"? Physchim62 (talk) 05:55, 27 June 2006 (UTC)

• I would prefer arenes or arene compounds, the Aromatic hydrocarbon page should be renamed accordingly V8rik 22:05, 26 June 2006 (UTC)
  • You see that little tag labelled "Move" at the top of the page? Physchim62 (talk) 05:55, 27 June 2006 (UTC)
    • No I do not...V8rik 18:22, 27 June 2006 (UTC)

Repetition in Health Effects

In the introduction to the "Health Effects" paragraph, it says something along the lines of "High exposure to Benzene can result in death, while high exposure results in drowsines..."

Just thought I would bring it up, as it does not flow, however I am no expert on the chemical, so I am not comfortable in editing the page. Forgive me If I am wrong.--Will James 08:18, 13 August 2006 (UTC)

Benzene in Unicode?

Hmm...what fonts DO support the character? Whatever default font I'm using (looks like Arial) doesn't seem to work. --M1ss1ontomars2k4 ^{(T | C | @)} 05:52, 20 August 2006 (UTC)

Exactly. So dont try to show it, just mention it.

Arial Unicode is a Unicode font provided with certain Microsoft products and OSes. I can't remember which ones altho I'm sure a Google search will find the answer in 5 seconds. It may also be dowloadable. There are also other unicode fonts which a simply Google should also find in 5 seconds Nil Einne 13:47, 10 March 2007 (UTC)

Story

An often-repeated story claims that after years of studying carbon bonding, benzene and related molecules, he dreamt one night of the Ouroboros, a snake eating its own tail, and that upon waking he was inspired to deduce the ring and structure of benzene

Can someone please provide a source for the above?--Alnokta 22:39, 4 February 2007 (UTC)

See recent edit additions that provide sources to this matter. 129.22.72.125 20:00, 22 March 2007 (UTC)

Benzene (data page)

Someone wants to merge it with this page. 68.39.174.238 02:58, 13 February 2007 (UTC) Can someone please provide a source for the above?--Alnokta 22:39, 4 February 2007 (UTC) Alnokta- I got your source, I recently found it in a Readers digest book called Into The Unknown. copyright 1981. Consultant who worked on the book Dr. Marcello Truzzi professor of sociology, Eastern michigan university. You can find a brief statement about it on page 224.--72.193.233.133 (talk) 18:55, 3 May 2008 (UTC)

Automatic addition of "class=GA"

A bot has added class=GA to the WikiProject banners on this page, as it's listed as a good article. If you see a mistake, please revert, and leave a note on the bot's talk page. Thanks, _BOT Giggabot (talk) 04:54, 10 December 2007 (UTC)

aplastic anemia

add. —Preceding unsigned comment added by 76.174.42.22 (talk) 06:20, 26 June 2008 (UTC)

STRUCTURE OF BENZENE ~ A-LEVEL DEFINITION

- 6 electrons shared over 6 carbons
- end on overlap of atomic orbitals forms
- DELOCALISED pi electron ring
- molecule is planar
- bond angle of 120 degrees

—Preceding unsigned comment added by 92.14.208.37 (talk) 00:55, 15 January 2009 (UTC)

Archive 1