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Chair perspective

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"A ring structure can be drawn in chair perspective." Huh? -- postglock 12:55, 20 September 2005 (UTC)[reply]

I believe the editor was trying to refer to the different arrangements of cyclohexane, where the chair conformation is the lowest energy form. I've expanded the section a bit to cover the use of dots & wedges in all three-dimensional molecules. GeeJo (t) (c) 15:25, 6 December 2005 (UTC)[reply]
I think that the chair is a teaching point used to explain optical isomerism, when drawn in a certain way a molecule could be made to look like a chair and it's reverse a non-super imposable chair - see [1] for details. Philipwhiuk (talk) 14:26, 6 January 2008 (UTC)[reply]

R

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Some articles like keytone and functional group follow the standard practice of using "R" (sometimes with subscripts) to represent arbitrary structures. This practice should be explained in this article including why "R" is the symbol chosen and what it stands for. (Radical (chemistry)?) I've added the same note to Talk:Chemical formula. -- Beland (talk) 16:15, 19 April 2008 (UTC)[reply]

Origin

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Hey, the history is completely missing! Was is Edward Frankland in its Lecture Notes for Chemical Students (1866) who introduced the graphical notation (see the book at Google books)? -- Nichtich (talk) 15:12, 25 May 2008 (UTC)[reply]

Example?

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The article says "Their structural formulae are shown at right:" - but I don't believe they are...

Diagrams are shown indicating the arrangement of atoms, but the actual structural formulae (to my understanding) are not shown. For instance, for isobutane, in the structural formula CH(CH_3)_3, indicating than the central sub-structure should be written first?

Sorry if this is a really silly point / question - I'm looking at this article for a reason :-) 123.243.228.66 (talk) 12:40, 7 June 2008 (UTC) The is nothing about aromaticity and the different ways of representing it86.146.202.24 (talk) 18:53, 31 March 2014 (UTC)Philip Jewess[reply]

"Unknown" projection for fructose = example of anomers

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Br77rino added today a structure for fructose with a squiggly line which he said has an "unknown meaning", and added in the edit summary "trying to get an answer". In fact the two possible ring structures are called anomers and are in chemical equilibrium with each other and also with the open-chain structure. The ring continually opens and closes, and when it closes it sometimes closes in one stereochemistry and sometimes in the other. For more details see Fructose and Anomer. Dirac66 (talk) 02:22, 26 July 2010 (UTC)[reply]

page reorganization and elaboration

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Page reorganized, and the explanations elaborated further.

[I did some editing here not noticing that I was not logged in. All edits for 9/10/2010 are mine.]

--Hansonrstolaf (talk) 19:44, 10 September 2010 (UTC)[reply]

Lewis Structures

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I don't believe it is proper to say that Lewis structures may not include dots for lone pairs. My understanding is that if you do that, it's a Kekule structure (as shown here). At least in practice, students who fail to indicate electron pairs when asked to draw a "Lewis structure" are going to get marked off. Perhaps some research should be done into this.

Bob Hanson, St. Olaf College--Hansonrstolaf (talk) 16:40, 10 September 2010 (UTC)[reply]

Um, are we reading the same article? The Lewis structure section clearly states that Lewis structures SHOW lone pair or unpaired electrons, so what is the problem?
Also, since you have added two new sections, I have placed them at the end as on most talk pages. Dirac66 (talk) 19:53, 10 September 2010 (UTC)[reply]
Sorry, I see now. The lone pairs were not mentioned or in the diagram previously and you have just added them. It is correct now. Thank you. Dirac66 (talk) 19:59, 10 September 2010 (UTC)[reply]

Limitations of Structural Formula Representations

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Should there be a section about some of the limitations of the Structural Formula? For example, differences in convention of representing dative bonds, aromaticity, tautomerism and other dynamic effects, atropisomers, salts, solvates, etc. I believe that a nod to George Box's "all models are wrong..." would make the article more complete and informative. — Preceding unsigned comment added by Bogtastic (talkcontribs) 16:51, 15 March 2018 (UTC)[reply]

Spatial representation

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I suggest we clarify that dashed and solid-vedge bonds are used to depict a spatial (a three-dimensional structure or) distribution of atoms in molecules. AXONOV (talk) 17:16, 25 May 2022 (UTC)[reply]

I'm having trouble with their terminology and the arrow pointing. "A filled wedge indicates that the atom is in the front of the molecule; it is pointing above the plane of the paper towards the front. A dashed wedge indicates that the atom is behind the molecule; it is pointing below the plane of the paper."

If you think of these wedges as arrowheads, really, they're all pointing TO the plane of the paper. A solid wedge/arrowhead indicates the atom is in front of the plane of the paper, and the arrowhead points from the atom in front, to the plane of the paper (screen). A dashed wedge/arrowhead indicates that the atom is behind the level of the paper, and its wedge/arrowhead points from the atom behind, to the plane of the paper.

What's the standard terminology for this? Is this why organic chemistry is hard, because you're using terms with meanings that are the opposite of what they are intuitively? Or, maybe just the description is wrong? Maybe we should use the word "indicates" instead of "points"? Shouldn't there be at least a sentence explaining the confusion? OsamaBinLogin (talk) 03:15, 16 March 2024 (UTC)[reply]

Wiki Education assignment: Honors Organic Chemistry I

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This article was the subject of a Wiki Education Foundation-supported course assignment, between 22 August 2022 and 2 December 2022. Further details are available on the course page. Student editor(s): AnjaliJolie, Asrija7 (article contribs).

— Assignment last updated by DavisGL529 (talk) 21:24, 15 November 2022 (UTC)[reply]