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Substantial Changes Planned

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This is just a notification that I am planning on adding a large amount of information to and reorganizing this article over the next several weeks. Because I plan on making major edits, I wanted to give fellow users a "heads-up" before I make such changes. B Levin13 (talk) 19:46, 27 October 2013 (UTC)[reply]

Much better, except for molecular diagrams

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To B Levin13: Following your recent edits, I think that the article is in general much clearer as well as more complete. One flaw, however, is the molecular diagrams for tetrahedral molecules. For example, in the first diagram for CH3F, the carbon seems to have only one C-F and two(!) C-H bonds. The line which should be the third C-H bond is too short and perpendicular to the line joining the C to the last H. It should be a dotted line joining the C to the last H. And most of the other tetrahedral molecules in the article have the same problem.

Can you redraw these diagrams? Or a simpler way might be to use diagrams from the articles on each of these molecules. For CH3F, the article on fluoromethane has an infobox with the more correct diagram which I have shown here. The diagram size of course can be varied. Dirac66 (talk) 03:33, 9 December 2013 (UTC)[reply]

I've drawn so many of these molecules that I see what I want to see, not what I've actually illustrated! I agree with your assessment and will recreate those images, although it might take me a week or more to get to it. My hesitation with using previously made images is that the the orientations will vary greatly. My hope was that by using the same formatting for all of the images in a particular table it would be easier to follow. Regardless, I will deal with the images over the next week or so. I appreciate the feedback! B Levin13 (talk) 08:54, 10 December 2013 (UTC)[reply]

While reading through the article, I noticed this table in the Bond angles section.

Molecule Bond angle between substituents
Skeletal structure of dimethyl ether.
Dimethyl ether
111°
Skeletal structure of methanol.
Methanol
107-109°
Skeletal structure of water.
Water
104.5°
Skeletal structure of oxygen difluoride.
Oxygen difluoride
103.8°

I noticed that the table omits hypofluorous acid, which has a bond angle of 97.2°, which is less than that of oxygen difluoride even though fluorine is more electronegative than hydrogen. Doesn't this contradict Bent's rule, and shouldn't it be explained in the article? Care to differ or discuss with me? The Nth User 20:16, 21 April 2019 (UTC)[reply]

The article says that the list of molecules is taken from Bent's 1961 paper, so there would be nothing about HOF. However actually HOF is several degrees less than water as expected; the question should be why is the OF2 angle so large, and barely smaller than the water angle. So it might be useful to check Bent's paper and see exactly what he says about OF2 in comparison with water. Dirac66 (talk) 00:31, 23 April 2019 (UTC)[reply]
I also noticed that the article states "VSEPR cannot explain why the angle in dimethyl ether is greater than 109.5°." but finally does not give a satisfactory reasoning for the question raised.
I would also recommend not to discredit VSEPR in such a way as the text "Unlike VSEPR theory, whose theoretical foundations now appear shaky ..." does. It has a completely different background and is a very succesful model in chemistry. A VSEPR, Bents rule cannont make quantitative predictions and for instance fails describing the big difference in bond angles between nitrogen and phosphorus halides in contrast to the small differences between P, As and Sb halides. NorbertMitzel (talk) 08:58, 4 May 2023 (UTC)[reply]

Wiki Education assignment: CHEM 300

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This article was the subject of a Wiki Education Foundation-supported course assignment, between 6 September 2023 and 7 December 2023. Further details are available on the course page. Student editor(s): Thanhthe3200, KTCpscChem (article contribs). Peer reviewers: Sshoore, 1597 CE, Kekekandy, Chmi1.

— Assignment last updated by CHEM 300 UBC CJA (talk) 18:01, 8 November 2023 (UTC)[reply]