User talk:Walkerma/Archive1
This is an archive of past discussions with User:Walkerma. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
For other talk page archives see User talk:Walkerma/Archives. Other close archives include:
Archive2 — Archive3 — Archive4 — Archive5 — Archive6 — Archive7 — Archive8 — Archive9 — Archive10
Chemistry
I've decided to answer most of your question on my own talk page because of it's length. You have some good ideas, so I suggest you visit Wikipedia: WikiProject Elements and Wikipedia: WikiProject Chemistry to let other chemists know and start moving pages to their proper names, after carefully reading the help pages on moving pages, especially with regard to double redirects. Good luck and don't hesitate to contact me again if you have to. :-) [[User:MacGyverMagic|Mgm|(talk)]] 09:22, Nov 24, 2004 (UTC)
Pictures of chemical compounds
Well, I didn't do much. All I did was photograph them with a closeup lens (I think it was 10 diopter, but am not sure right now) on a 4 megapixel camera, then individually cut them out using Photo Shop Elements. The photos currently available are the original version direct from Photo Shop Elements with no scaling and are about 600 pixels across. (Originally I was planning on only uploading the 125 pixel scaled versions, but I uploaded both and the 125 pixel versions have been deleted since Wikipedia can now handle the scaling itself, and the larger version looks much better)
If I was going to add a label to the photos I'd do it after cropping with the text features of Photo Shop Elements (not on a paper card). Some of those paper cards seem to be hard to read (e.g., perspective effects).
Mostly I'm just glad the photo "project" is over for me :-) It took all of one day to take the photos, many evenings to edit them, and alot of time to upload on my home dialup connection. But I had access to the kit (I had bought and donated it to a science school, so all I had to do was ask them to let me take the photographs when I donated some other things to the school) and simply couldn't resist the opportunity to "donate" the kit again :-) . -- RTC 16:39, 6 Dec 2004 (UTC)
Suggested changes to inorganics table
Hi Walkerma,
maybe you should add your message on my talk page to User_talk:Mykhal so that he will read it.
I have a few suggestions to your inorganics table (maybe we can also apply some of them to the 'main table'):
- THANK YOU for your feedback! I've been waiting for comments like these for a couple of months! I'm still fairly new to Wikipedia, but I felt strongly that we would never get a large number of decent pages on compounds with the original table because it was too long, too obscure, and it wasn't tailored for organic or inorganic. However I didn't know enough to be able to make all of the changes you did. Also I don't know enough about Wikipedia protocol to know whether my changes break any rules. I have posted my thoughts indented right after your comments below.
- No table width. Instead we can use <br> for linebreaks in a table cell.
- Fine- I have little idea what I'm doing in Wiki markup, I just copy & paste!
- 'Name' into the title row and 'Other names' under 'general' so that the layout with the columns will not be broken.
- OK
- Removed that grey horizontal ruler below the image.
- OK
- 'Molecular weight' in g/mol instead of amu. It's identical, but nobody uses and understands the latter.
- OK, I agree- I was just following the standard table, but I prefer g/mol myself. However, to be strictly correct the value in g/mol should be called molar mass. I have a copy of Hill & Petrucci's General Chemistry open at the moment, chapter 3, and it says this explicitly (p86 in the 2nd edition). So, which do you prefer, molecular weight in amu or molar mass in g/mol?
- Molar mass in g/mol, obviously. Molecular weight is a redirect to that article.
- OK, I agree- I was just following the standard table, but I prefer g/mol myself. However, to be strictly correct the value in g/mol should be called molar mass. I have a copy of Hill & Petrucci's General Chemistry open at the moment, chapter 3, and it says this explicitly (p86 in the 2nd edition). So, which do you prefer, molecular weight in amu or molar mass in g/mol?
- [[Systematic name|IUPAC name]] should have been [[IUPAC name|Systematic name]]. Maybe 'Chemical name'?
- This is more of a problem. On Wikipedia we currently have two main pages that cover IUPAC nomenclature- the "official" name on Wikipedia. For organics, the page IUPAC nomenclature does a great job of explaining the system, but there was (until I added a link ten minute ago) nothing about inorganics. However inorganics are covered on the page systematic name, but this page gives very little on organics. However, for a title in a template, I think "IUPAC name" is the correct term, because there are several systems for systematic naming (for example, the CAS system, which would refer to 2-propanol as 1-methylethanol instead.
- I prefer [[IUPAC name|Systematic name]] because we do need a clear name for that field.
- This is more of a problem. On Wikipedia we currently have two main pages that cover IUPAC nomenclature- the "official" name on Wikipedia. For organics, the page IUPAC nomenclature does a great job of explaining the system, but there was (until I added a link ten minute ago) nothing about inorganics. However inorganics are covered on the page systematic name, but this page gives very little on organics. However, for a title in a template, I think "IUPAC name" is the correct term, because there are several systems for systematic naming (for example, the CAS system, which would refer to 2-propanol as 1-methylethanol instead.
- 'CAS number' without square brackets.
- It is standard practice in the chemical literature to include square brackets. I realise that one can find MSDS sheets etc without these on, but I was the information specialist at a chemical company for many years, and it really is pretty standard. Does it really screw up things to include square brackets?
- OK
- It is standard practice in the chemical literature to include square brackets. I realise that one can find MSDS sheets etc without these on, but I was the information specialist at a chemical company for many years, and it really is pretty standard. Does it really screw up things to include square brackets?
- Do we really need the temperature in Kelvin? I'm not sure, maybe for inorganics.
- I think of this as unnecessary myself, but I have seen people who advocated removing all reference to "non-SI" units such as Celsius and ONLY using K. Scary! I think adding the value in K should be enough for such purists, and also for physicists who may well prefer Kelvin. For organics, stick with Celsius only- physicists are much less likely to use these pages.
- left K (with comment)
- I think of this as unnecessary myself, but I have seen people who advocated removing all reference to "non-SI" units such as Celsius and ONLY using K. Scary! I think adding the value in K should be enough for such purists, and also for physicists who may well prefer Kelvin. For organics, stick with Celsius only- physicists are much less likely to use these pages.
- ':' removed after 'Hazards'.
- OK
- 'Solubility': Water uppercased.
- Thanks
- No unit links. People who don't know the units are probably not that interested in the value - or they can click the description link to the left. Also, repeatedly linking to the same article is bad...
- Thanks again, I'd often wondered what was considered good/bad on that. I had just copied the "standard table" format there.
- The rows under 'Related compounds' are just an idea...
- A great idea! However, we can't use words like anion/cation, unless this is to be ONLY for ionic compounds. I was expecting to be using this for things like PBr3, where there are no anions, or PCl5, where the cation/anion are PCl4+ and PCl6-! But certainly for ionic metal compounds, the anion/cation version would be much clearer. Do we need two short form inorganic tables?
- added comment
- A great idea! However, we can't use words like anion/cation, unless this is to be ONLY for ionic compounds. I was expecting to be using this for things like PBr3, where there are no anions, or PCl5, where the cation/anion are PCl4+ and PCl6-! But certainly for ionic metal compounds, the anion/cation version would be much clearer. Do we need two short form inorganic tables?
- I think the light-pink shade of the left column is very ugly...
- Again, I just copied the standard table, but I like your version just fine.
Keep on with your good (& hard) work! Cacycle 21:11, 31 Jan 2005 (UTC)
- Thanks, and the same to you!Walkerma 18:06, 1 Feb 2005 (UTC)
I have put up a version that (I think) includes most of your suggestions. Upon reflection I decided to leave in some of the unit links, because I don't think they intrude much on the page (indeed, having them in blue may enhance the clarity), and my experience teaching chemistry has been that many people DON'T know what things mean, even at the college level. The 5th grade class (11-12 year olds) at my daughter's school (in the US), for example, do a project about the periodic table, and if any of them look up things on Wikipedia some of them may not know what K means, or even °C. Please feel free to comment further. Walkerma 16:43, 7 Feb 2005 (UTC)
See my comments above. The units are explained in detail by the article link to the left (i.e. Temperature, so I don't see the need for repetitive unit links. I have changed the template according to the discussion above. I have also added a lot of comments, please have a look at the plain text. Cacycle 19:24, 18 Feb 2005 (UTC)
Great! Thanks a lot! I was planning on working on that this weekend, depending on your feedback, but you've done a much better job than I would have done. I did put up a page on [[chromium(III) chloride using the tentative version (any comments?), and I will be putting up zinc chloride today, as I wanted to see how they looked. Assuming there aren't any big problems, I'll start using the new template for all my contributions from now on. I did find with the variable width I have to be careful that the table doesn't get too wide. Thanks again, Walkerma 19:55, 18 Feb 2005 (UTC)
Walkerma/Archive1 Walkerma/Archive1 | |
General | |
---|---|
Systematic name | ? |
Other names | ? |
Molecular formula | ? |
Molecular weight | ? amu |
Appearance | ? |
CAS number | [?-?-?] |
MSDS | Walkerma/Archive1 MSDS |
Bulk properties | |
Density | ? g/cm3 |
Solubility | Water: ? g/100 cm3 (? °C) |
Melting point | ? °C ( K) |
Boiling point | ? °C ( K) |
Hazards | ? |
Structure | |
Coordination geometry | ? |
Crystal structure | ? |
Hydrates | ? |
Related compounds | |
Related anions | ? |
Related cations | ? |
PNGs vs. GIFs
There are several main differences between PNGs and GIFs:
- PNGs can have up to 24-bit color depth, for a maximum of about 16.7 million colors. GIFs are limited to just 256 colors, so you may have to reduce the color depth of a full-color image, which can result in bad-looking dithering. (PNGs can also be used for 256-color, 16-color, or 2-color images, like GIFs can.)
- PNGs have what is known as an "alpha channel", which can be used to make parts of the image partially or fully transparent. GIFs support transparency as well, but not with an alpha channel; with a GIF, any pixel is either fully transparent or fully opaque. The main problem with partial transparency in PNGs at the moment, however, is that Internet Explorer doesn't support it well.
- The PNG algorithm was specifically designed to be free of any patents. Unisys claimed intellectual property rights over part of the GIF algorithm, which caused quite a stir in the late 1990s. The relevant patent expired in 2003 in the United States, however.
- GIFs are probably more widely supported in browsers, but all recent versions of major browsers support PNGs.
There aren't many reasons to prefer a GIF to a PNG, unless you're worried about compatibility with old browsers.
In either case, for line art, maps, flags, diagrams, and so on—images with clearly-defined edges and few colors—PNGs and GIFs work much better than JPEGs, because they use lossless compression. The lossy compression of JPEG introduces "fuzz" into the picture and actually results in a larger file size. This fuzz is quite obvious in images with clearly-defined edges, but invisible in photographs. JPEGs are still the best choice for photographs, paintings, photorealistic computer art, and so on, since the "fuzz" is invisible and JPEG compression works better than lossless compression does for these images. —Bkell 22:10, 15 Feb 2005 (UTC)
- If you're interested in the current status of PNGs, including browser support, try visiting the semi-official current status page. Netscape and Internet Explorer have supported at least basic PNGs since 1997. As far as Wikipedia images, I'd recommend PNGs rather than GIFs, since they're more versatile. Among other reasons, if someone wants to add more advanced features to the image later, they will be able to use PNG features without having to rename the file. —Bkell 22:21, 15 Feb 2005 (UTC)
Hydrochloric acid
The hydrochloric acid is in the process to be nominated for Featured Article, see the discussion at Wikipedia:Peer review/Hydrochloric acid/archive1. I think the article needs some polishing. Maybe you can provide an image of a hydrochloric acid bottle, a cylinder, or an HCl generator. Unfortunately I don't have a camera. Cacycle 22:32, 13 Mar 2005 (UTC) Maybe even a fuming bottle of conc. HCl... Cacycle 10:21, 14 Mar 2005 (UTC)
- I will try to get to this tomorrow, and also I will take a careful look over the HCl pages.Walkerma 20:39, 14 Mar 2005 (UTC)
- I have taken a few pictures, but I have to download them then upload them. Walkerma 17:12, 17 Mar 2005 (UTC)
- Please see my suggestions in Section 1.4 of Wikipedia:Peer review/Hydrochloric acid/archive1. H Padleckas 18:53, 17 Mar 2005 (UTC)
- Sorry, I'd already done the photos! A titration pic would be nice, I agree. However setting up titrations would be a big hassle at the moment, but maybe I can take a picture when the students get to do this; alas, not until the autumn. By the way, H, I strongly endorse your comments on chemistry pages- though don't underestimate the number of people who can understand these things!
- I agreed with Cacycle about the polishing, partic. the chemistry section, so I've done a rewrite. I think it reads more clearly now, but others are welcome to rewrite my rewrite till we get it right. Walkerma 06:17, 18 Mar 2005 (UTC)
- I have been very busy with a brand new baby but I will try to get a better HCl picture done in the next day or two. Walkerma 23:00, 21 Mar 2005 (UTC)
I have made some (hopefully) final comments on Hydrochloric acid at the bottom of Wikipedia:Peer review/Hydrochloric acid/archive1. Also, if you haven't seen them already, I wrote some remarks on the Talk:Hydrogen chloride page of the Hydrogen chloride article, which is not quite finished yet. Once my comments are resolved, I think Hydrochloric acid will be ready for FAC nomination. H Padleckas 19:47, 31 Mar 2005 (UTC)
Zinc chloride article
Hi, you put an impressive amount of detail on chemical reactions in the Zinc chloride article.
I was looking at the picture of the Negishi coupling reaction which shows ........... 1-ethoxy-1-(zinc chloride)ethene being treated with 2-bromo-1-phenylethene and a Pd...... catalyst giving
2-ethoxypropene. I would expect a Negishi coupling to yield 3-ethoxy-1-phenyl-1,3-butadiene. Can you check this out please? H Padleckas 22:55, 2 Apr 2005 (UTC)
- Thanks for spotting this! It is a problem with Wikipedia, it seems- it chopped the end off the picture, making it look like a methyl on the end. I've reduced the size of the picture and hopefully that will solve it. Walkerma 23:37, 2 Apr 2005 (UTC)
- Correction- it wasn't a fault with Wikipedia, it was my fault, after all! Walkerma 19:50, 3 Apr 2005 (UTC)
My ongoing plans for Wikipedia articles
So we are not both duplicating effort on the same topics, I will tell you about some of my ongoing plans for Wikipedia articles on chemical compounds. For chemical structures, I usually upload the images into Wikimedia Commons so that all Wikimedia can link to my images. For certain very article-specific images, I sometimes upload the image directly into the specific Wikimedia (like Wikipedia) that will use it. In some cases, one article can cover several closely related compounds. For example, before I started working on Wikipedia, there was one article covering all three xylene isomers and one article covering all three isomers of phthalic acid. I plan to start an article on benzenediols (catechol, resorcinol, and hydroquinone) and possibly another article on toluidines someday. Also, I plan to expand the Ethanolamine stub a bit to mention the differences between monoethanolamine, diethanolamine, and triethanolamine. In Wikimedia Commons, I have uploaded one image with the chemical structures of Catechol, Resorcinol, and Hydroquinone and another image with the chemical structures of the three toluidine isomers. Also in Wikimedia Commons, I have separate images of each of the three ethanolamine compounds mentioned above, which someday I plan to insert into the Ethanolamine article, although I plan to discuss only monoethanolamine in more detail.
H Padleckas 19:47, 31 Mar 2005 (UTC)
- I wrote up a short article on Benzenediols, but I have not done any work on Toluidines or Ethanolamine yet. H Padleckas 16:45, 18 Apr 2005 (UTC)
- V8rik wrote up a rather short article with a Table of Properties on p-toluidine and I expanded it to cover the o-, m-, and p-isomers. The table will need to be finished up still and this article on Toluidines could use a little more work. I added Tables of Properties covering o-, m-, and p-isomers to the Xylene and Cresol articles and I am still working on a similar table offline so far for Benzenediols. Someday I plan to prepare a similar table for Isomers of Butylene. I have uploaded pics of MEA, DEA, and TEA (mono-, di-, and triethanolamines) into WikiCommons, but I have not edited the Ethanolamine article yet. H Padleckas 05:07, 26 July 2005 (UTC)
In the Hydrochloric acid article, TDI and MDI are both mentioned twice. In the Isocyanate article, I have briefly described what they are and put in a chemical structure image of the two most common industrially used isomers of TDI. I am currently working on a picture of the MDI structure. When I do upload that image, can you please check to make sure the small blue numbering of the atoms is correct for this compound? H Padleckas 19:47, 31 Mar 2005 (UTC)
- I just finished making and uploaded the MDI image into Isocyanate. H Padleckas 00:39, 1 Apr 2005 (UTC)
Regarding thionyl chloride, in all of the several websites I've seen its chemical structure, there is always a double bond shown between the sulfur and oxygen atoms. However, it seems logical to me that this bond would share only one electron pair, with both the electrons coming from the sulfur. If that one electron pair resulted in one covalent bond between the S and O atoms, the sulfur would have a positive charge and the oxygen a negative charge. Does the double bond designation stand for one double bond and one ionic bond? Is it wrong to think of a chemical structure with a single covalent bond and opposite charges on the S and O atoms? In similar cases in old books, I've seen a single bond with an arrow going from the sulfur to the oxygen, showing both electrons from the bond came from the sulfur. Is this designation now obsolete?
H Padleckas 19:47, 31 Mar 2005 (UTC)
I've just added a Table of Properties to Thionyl chloride based on the template link you gave me on my User talk:H Padleckas page. The table itself looks pretty good except it is below the text on the right side.
- How can I move the table up to the top of the article on the right side?
- In the text of the article itself, after practically every word in a link, the blank space afterwards was lost. Insertion of the table must have had something to do with this. How can this be fixed?
H Padleckas 21:45, 31 Mar 2005 (UTC)
- This looked wierd, didn't it! I compared my pages with this and there should have been a |} at the end of the table, and inserting those two characters fixed everything! I deleted several of the names from the article, since these are now given in the table.
- Thank you for fixing this. H Padleckas 21:28, 1 Apr 2005 (UTC)
- I think it's a great idea for us to share plans. My plans for compounds are listed on the WikiProject Chemicals to do list, this was updated only recently so you can see there what I'm planning. I decided in November or so that it would be nice for there to be at least one decent compound page per element, excluding obscure elements. Although I'm an organic chemist, I'm aware that many of the compounds I use are simple inorganics, and I found that even these weren't covered well in Wikipedia. I though of oxides at first, but decided instead to write pages on metal halides, particularly chlorides, as being both important and also typical metal salts, unlike oxides. Also my research uses a lot, so I was able to take pictures easily (I even have HfCl4, ErCl3 pictures, yet to upload). Other than NaCl, there were virtually no decent pages on metal chlorides before, so I decided to work through the periodic table. Even CaCl2 was very poor, AlCl3 didn't even exist. So after cutting my teeth on a few lanthanide chlorides (Ce, Pr, Nd, Sm and Dy) I settled on a standard short form table that worked well. Then I ploughed through chlorides of Li, K, Mg, Ca, Sr, Ba, Al then switched to transition metals Cr, Mn, Fe, Co, Cu (both) and Zn. I just have FeCl2 and NiCl2 left from the first row (TiCl4 is not too bad already), I did CdCl2 just today (do you like my crystal drawing, a first for me!), and I'll add the few remaining ones I listed over the coming weeks. I have about seven books on the topic in my office at home to give me everything I need, so I can be quite productive. My idea is that when some kid is doing a school project on (say) copper, they can find some significant information as well as a couple of pretty pictures. I think I'll get bored before I get NbCl5 done, but I'll do ones I have pictures of like Hf and Au.
- My philosophy when writing articles seems to be different from many contributors. Although I do sometimes just add a sentence or two to an article, this is usually just to correct an error, or because I see a major fact is missing. Instead I like to put together an full-length article in MS Word at home (where I don't have internet) over several days or even weeks. When I take a break from marking lab reports, I write a section of a page. That way the page ends up being pretty much complete when uploaded, and well-rounded- I've had time to mull over all aspects.
- I often wrote articles or sections of them offline using AOL files in order to minimize time online. Then when I'm online I use AOL's Edit-Copy and Paste to enter the changes into Wikimedia. I also make pictures offline, then when they're ready, I upload them online. H Padleckas 21:28, 1 Apr 2005 (UTC)
- Personally, if I look on Wikipedia an article on George Washington, I'm likely to want to know more than his dates of birth and death. Likewise, if I look up manganese(II) chloride, I may just want to know its MP, but I may also want to know rather more about it if I plan on using it or writing about it.
- A problem I see a lot is that people put up stubs that contain errors or non-information (take a look at 2-bromo-1-chloropropane for an example of the latter), and I find I waste more time working around these than I would if there was no page at all! Often the page needs renaming to a IUPAC name- I'm no lover of IUPAC but it is at least a standard, and it's what Wikipedia has chosen so let's use it. Also you have to be careful not to hurt the writer's feelings (I try, anyway!). The other thing one finds is a longer article where much of the article relates to one particular use or aspect (see copper(I) oxide)- this is often very good information, but it's not exactly balanced. Once I give a page a major rework, I try to balance these things out, but you feel bad if you delete stuff like that just in the name of balance.
- I admit, though, I did enjoy getting the chance to delete hundreds of really silly listings when I created List of organic compounds! Many of the compounds listed in List of compounds won't even have a page a hundred years from now, unless it is just to give a MP and formula.
- As I have worked through these pages I found that certain compounds crop up a lot- thionyl chloride being one of them. Ph3P and Ph3PO would also be valuable to have, as well as PBr3, and I plan to do those soon. I notice someone has started a BF3 article, another compound on my hit list.
- Once I get done with these, I may work on some oxides, but I think I'd like to have a change of scenery and do a few organic reagents I am familiar with such as MCPBA, triflic anhydride, TFAA. This seems to be an area where things are lacking, and once done it would be much easier to write decent articles on things such as Baeyer-Villiger oxidations. I'd also like to cover a few basic "building block" organic molecules like iodomethane. I was thinking of taking a stab at ethylbenzene- an important precursor to styrene I understand, yet it has no page currently. Or perhaps it is more in your area?
- I'm the one who put the picture of ethylbenzene being dehydrogated to styrene in the Styrene article. However, I didn't have that much practical to say about ethylbenzene that wasn't already in the Styrene article, so I did not create a new "Ethylbenzene" article. H Padleckas 21:28, 1 Apr 2005 (UTC)
- I wrote up an Ethylbenzene stub anyway and I made an Image:Ethylbenzene.PNG picture for it. If you want to work on Ethylbenzene, go ahead; I have other things to do in the meantime. H Padleckas 16:45, 18 Apr 2005 (UTC)
- I'm the one who put the picture of ethylbenzene being dehydrogated to styrene in the Styrene article. However, I didn't have that much practical to say about ethylbenzene that wasn't already in the Styrene article, so I did not create a new "Ethylbenzene" article. H Padleckas 21:28, 1 Apr 2005 (UTC)
- Another crying need is for some articles that either currently don't exist at all or are pretty basic, yet they cover important topics. In fact with organic synthesis I got so frustrated that there was no article describing my field of work I took a break from chlorides to write it. I also revamped the chiral synthesis page (though I'd prefer it to be called asymmetric synthesis). I think the aldol reaction page needs a lot of work. But probably the biggest gap is on the chemical industry, where there should be a whole slew of full-length articles. What is the world's petrochemical industry worth? A couple of trillion Euros per year? About 10% of the world economy? (I'm guessing) It gets three lines in Wikipedia.
- I previously noticed that petroleum refining and petrochemicals processing are rather weakly covered in Wikipedia. Significantly more could be added about the chemical processes themselves. I may attempt to do so when I feel more ambitious. I once wrote a nice school paper on catalytic reforming. I wish I could find that again.
H Padleckas 21:28, 1 Apr 2005 (UTC)
- I previously noticed that petroleum refining and petrochemicals processing are rather weakly covered in Wikipedia. Significantly more could be added about the chemical processes themselves. I may attempt to do so when I feel more ambitious. I once wrote a nice school paper on catalytic reforming. I wish I could find that again.
- The only reason I haven't worked on this is that I would like to do it properly- take out a bunch of books from the library, go through my old copies of Chem & Eng. News, and write some well-researched articles that Enc Britannica would be proud to include. The topics are too important to just do a bad job on. I'd really like to write a page on the fine chemical industry- I worked in it for 12 years. Of course when I finish all these I'll probably be dead!
- Regarding your questions, I did a quick bit of research and I think your nos. are right for MDI, I think NCO groups are treated as halogens are, making them lower priority than the CH2. Don't sue me if I'm wrong!
- Thanks for checking that out for me. H Padleckas 21:28, 1 Apr 2005 (UTC)
- Regarding the structure of SOCl2, don't get me started! My PhD thesis is titled "New reactions of the sulfinyl group......." so I feel more able to give my opinions freely on this. From what I have read, your are indeed correct, -O-S+Cl2 is probably rather closer to the truth than O=SCl2. The same is true for the famous "P=O double bond". In fact both are resonance forms, and so there is both dipolar and double bond character involved. Of course charge separation is bad in res forms, but the pi overlap between a large S (or P) and small O is not nearly as good as in C=O, also the S (or P) has to expand its octet to make the double bond. And remember, nitrogen seems quite happy with charge separation in nitro groups. I don't think we should write sulfuric acid with a 2+ charge on S, but those aren't pure double bonds either. I actually like the old arrow notation, but "dative bonds" are considered rather dubious by the purists these days so we're not allowed to write them too much. So when they fell out of favour, I think the double bond version became standard through laziness- it's much easier to write S=O on a typewriter or word processor, and much easier in ChemDraw too. (You should have seen the problems my students had drawing a nitro group in the Cache modelling program today!). So by all means change the structure if you dare, if not, I'll probably add something about bonding when I get the time. I notice that in my dissertation I wrote all my sulfoxides as -O-S+, but CF3SOCl (triflinyl chloride) with S=O, so I guess I'm inconsistent!
- Thanks for the explanation. H Padleckas 21:28, 1 Apr 2005 (UTC)
- With any new compounds you write, can you be sure to add them to List of organic compounds as well as List of compounds (until the latter disappears)? Please keep in touch and let me know what you're doing too! Walkerma 06:03, 1 Apr 2005 (UTC)
Sodium chloride picture
Hi Walkerma! Re: Image:Sodium_chloride_crystal.jpg: The jpeg image format is not really suited for text and graphical images, it's only for photographies. Better use the lossless and compressed png or gif formats. That way you can prevent those ugly artifacts. Cacycle 17:31, 1 Apr 2005 (UTC)
- I expected to use png, so I actually tried png first direct from the scanner, and it gave me an enormous file for the initial scan (3.8 MB). So then I saved it as a jpg file and it came down to 0.79 MB. After getting your message I tried converting the jpg to gif and it came out around 1.0 MB. The initial scan was then cropped to give the NaCl file and also one of Cadmium chloride, then I resized each down to a reasonable size. I'm using IrfanView as an editor (I'm much more familiar with it than with Photoshop, though the college recently bought us the latter)- is that the problem? Do you have any suggestions for making the files better? I've uploaded Image:Sodium_chloride_crystal.png (made from the original scan exactly as with the jpg file, but it's 118 kB vs 33 kB for the JPG), so perhaps you can see what I'm doing wrong. Thanks, Walkerma 18:27, 1 Apr 2005 (UTC)
- I have taken a look at your new NaCl *.png pic. I think you scanned in a pic on paper (or whatever) as if it were a photograph, using a scanner. All the detail of a full photograph was retained in a *.png file. As a result you have stored considerably more information than the minimum required for a good diagram. Why did you scan the picture? Didn't a computer make it for you to begin with? Couldn't you transfer the file from computer-to-computer? May I try to fix this problem for you? H Padleckas 21:28, 1 Apr 2005 (UTC)
- I would welcome any help. I feel like such a computer amateur on Wikipedia, everyone else seems to know so much more than me! I do indeed scan everything, including things like the GIF files that are particularly abundant on the zinc chloride page. I didn't scan the NaCl pic as a photo, I scanned it as a colour document. I am very familiar with IsisDraw, downloadable for free from [www.mdli.com MDL] and I used that for drawing the NaCl picture (believe me, it's not designed for that, but that's what I'm most comfortable with). As far as I know there is no way to take the IsisDraw file and directly make a GIF or PNG file from it. I do know ChemDraw a bit too, but that got lost when they upgraded my PC. So please, if you or Cacycle can help me get the pictures to look sharper, I'd welcome it. Thanks, Walkerma 23:04, 1 Apr 2005 (UTC)
I stumbled across Inorganic stylesheet1 when clicking through random pages. I don't believe that it should be in the main namespace, as it's not a real article but rather an editing tool. Can I suggest that you move it instead to something like Wikipedia: WikiProject Chemistry/Inorganic stylesheet? (By the way, cheers for all your good work). --194.73.130.132 09:49, 4 Apr 2005 (UTC)
- I moved this to Wikipedia: WikiProject Chemicals/Inorganic stylesheet1, though I can't get a picture in it there. Walkerma 20:32, 9 Apr 2005 (UTC)
Isn't this just the chemical infobox for inorganics?. See wikipedia:chemical infobox with a link off the Chemistry wikiproject, of course. Wim van Dorst 18:56, 2005 Apr 10 (UTC)
- It is indeed! The history of this is that I put up a template page that I could use myself, and suggest to others, then when Cacycle put up the organic infobox I added this page in there too. Use whichever form you prefer, they are basically the same. I was trying to bring some form of simple standard table to the inorganics, but even now I'm still learning the meaning of all of the Wikipedia systems! Walkerma 19:39, 10 Apr 2005 (UTC)
Methyl Mercaptan
I would appreciate any comments you may have regarding my request to move methyl mercaptan to methanethiol. Please leave any comments at Talk:methyl mercaptan. Thanks.
Darrien 05:39, 2005 Apr 7 (UTC)