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Rules used on this page

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The formulas in the list have been ordered according to these rules:

  1. Element A comes before element B, and B before C, &c.
  2. Element A comes before element Ai where i is a natural number.
  3. Element A2 comes after element A1, and A3 after A2, &c.
  4. Element Ax comes after element A.
  5. Element Ay comes after element Ax.
  6. Element Ayj comes after element Axi no matter what the natural numbers i and j happen to be.
  7. A comes before AB.
  8. AB comes before AC, and AC before AD, &c.
  9. A comes before A; A comes before AB.
  10. If element X comes before element Y, then compound AX comes before compound AY.
  11. Parentheses should be ignored unless two compounds with parentheses are the same except for the subscript of the parentheses: ABC comes before A(BC)2, and A(BC)2 comes before A(BC)3, &c.
  12. Brackets (for coordination complexes) should be treated similarly to parentheses: ignore unless there is a tie.
  13. The compound must have at least two atoms, otherwise it is an element or an ion, but not a compound. (The "dictionary" being a list of compounds.)
  14. Hyphens (for single bonds) are ignored unless there is a tie. Likewise for equals signs (for double bonds) and equivalence signs (for triple bonds).
  1. Structural formulae can only be included if they are linear (one-dimensional) alphanumeric strings all of whose atoms are explicitly labeled, e.g.: hexane may be included as C6H14, CH3CH2CH2CH2CH2CH3, CH3-CH2-CH2-CH2-CH2-CH3, or CH3(CH2)4CH3 but not as ASCII art in which six C atoms and 14 H atoms are arranged like six black pieces and 14 white pieces on a go board. Structural formulae which are two-dimensional or three-dimensional cannot be included, e.g.: structure of rhombic sulfur, aniline, tetraphosphorus decaoxide, α-D-glucose, β-lactose, ATP, cyclopentanoperhydrophenanthrene skeleton, protoporphyrin IX, myoglobin diagram. No Haworth projections, no Fischer projections, no quasi-linear diagrams which look like sentence diagrams. A formula is includeable iff it is a string whose characters are any of the following: (1) letters, in upper or lower case, or in italics; (2) numbers, subscripted, superscripted, or otherwise; (3) plus and minus signs, esp. superscripted; (4) parentheses; (5) brackets; (6) hyphens, equals signs, and equivalence signs; (7) asterisks (or interpuncts), spaces, and periods. (Note: minus signs might be used instead of hyphens for single bonds, since minus signs are slightly longer.)
  2. Dotted compounds (for complex ions) are first placed by ignoring the dot (interpunct or asterisk) and whatever comes after it, but if there is a tie with a neighboring compound then the compound after the dot will be considered. In particular, A * B comes after A. If C comes after B then A * C comes after A * B.
  3. If A comes before B then A * C comes before B.
  4. The same compound may be included more than once if it has more than one includeable formula.
  5. Different names for the same formula may be included, in which case they are separated by line breaks (<br>).
  6. A formula may refer to different structural isomers. In this case, the names of the different isomers should each be placed on a separate subrow in the table in alphabetical order, as shown below.
  7. If several isomers have a collective name, it should be given in parentheses below the chemical formula. Each distinct collection of isomers should be placed within a separate major row, with the formula repeated as necessary.
Benzenediol isomers
C6H6O2
(benzenediols)
catechol 120-80-9
hydroquinone 123-31-9
resorcinol 108-46-3

Anyone who wants to is invited to edit the dictionary, adding new compound formulas, removing formulas, adding alternative names for a given formula, adding hyperlinks from the name of a compound to its article, &c. just as long as the rules (or at least the most important ones, such as the first ten) are followed.

Questions

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  • Should hyphens, equals signs, and equivalence signs be included, or should they be removed from a formula before the formula is included in the list?
Regarding whether or not to include -, = etc in formulae, you need to consider what your naive student of chemistry is likely to find in their book. If the book uses both forms, then ideally you should have both. However, there are many cases (even simple ones like benzene) where you simply can't write the formula with text any other way than the molecular formula, C6H6. So I would suggest that you have a policy of initially just trying to write formulae without hyphens etc, then just add a few of the simpler formulae like butane later if you feel the need (this is what I think you did anyway!). Walkerma 03:45, 14 July 2005 (UTC)[reply]
En-dashes look better than hyphens for single bonds. Physchim62 11:15, 14 July 2005 (UTC)[reply]
I think, for consistency, it would be better to not include these. ᓛᖁ♀ 11:23, 13 September 2005 (UTC)[reply]
  • Should ions be included?
I suspect that it's not necessary to include hydrates, as this would just add a lot of extra work for little gain. If they are included, the normal Wikipedia format uses · for hydrates. For complexes, that format is rather obsolete (at least 50 years old?), the usual way these days uses square brackets, as you have used. If by complex you mean things like Lewis acid/base adducts (e.g. BF3·OEt2) then I think the middot is the way to go. Walkerma 03:45, 14 July 2005 (UTC)[reply]
I agree; hydrates do not seem to add much. ᓛᖁ♀ 11:23, 13 September 2005 (UTC)[reply]
  • Would interpuncts be preferable to asterisks for denoting complex ligations?
Middots should be used for hydrates, [square] brackets for complexes (except the simple P-block cases mentioned by Martin). Physchim62 11:15, 14 July 2005 (UTC)[reply]
  • Would it be appropriate to include organic shorthands such as Me, Et, and Ph?
The use of Me as an abbreviation of methyl is not to be encouraged (it causes problems for German speakers), other abbreviations should be listed at the appropriate place in the order of empirical formulae. Physchim62 11:15, 14 July 2005 (UTC)[reply]
  • If a compound can be described by more than one chemical formula, which should be included?
From looking at the organic compounds, the tables may get very unwieldy if parenthesized formulas are included. In my opinion, it would be better to avoid these as much as possible. ᓛᖁ♀ 21:08, 13 September 2005 (UTC)[reply]
  • This page is very long, and likely to become longer. Would the dictionary be better organized with a subpage for each letter?
  • Isn't aluminum chloride AlCl_3, not AlCl_2?
They are the same, so I have removed the second listing. -- Ed (Edgar181) 15:40, 27 November 2017 (UTC)[reply]

Page to delete

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Is this page in use anymore? Dictionary_of_chemical_formulas/F? If not it should be deleted. -Ravedave 06:36, 27 January 2006 (UTC)[reply]

Oh and so should: Dictionary_of_chemical_formulas/Merge/C30-C39 - Ravedave 06:37, 27 January 2006 (UTC)[reply]
The pages that have become redirects due to page moves could be deleted, I suppose, though there isn't a pressing need to. Note that Dictionary of chemical formulas/F and some other letters are transcluded by Dictionary of chemical formulas. The merging of Dictionary of chemical formulas/Merge is also not finished. ᓛᖁ♀ 06:54, 27 January 2006 (UTC)[reply]
User:Danaman5 created a category and I applied it to F since it wasn't on it. Good enough for me. -Ravedave 00:04, 8 February 2006 (UTC)[reply]

Categorization

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There were many uncategorized articles associated with this dictionary, so I created the new category "dictionary of chemical formulas" and placed everything associated with this dictionary into it. Feel free to change this system or suggest a better one, but for now I just felt that the articles needed to be categorized somewhere. Danaman5 23:53, 7 February 2006 (UTC)[reply]

Naming System

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Would it be beneficial to also include IUPAC name of the compound into the table as well? MathStuf 21:25, 11 April 2006 (UTC)[reply]

Check of CAS numbers

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When checking the checksums of the CAS numbers (last digit) with my script, I get the below errors. Hermann

AuF3      gold trifluoride    14270-21-9     Wrong checksum (correct: 4)
Ba(CN)2   barium cyanide      524-62-1       Wrong checksum (correct: 9)
CdTiO3    cadmium titanate    12104-14-1     Wrong checksum (correct: 2)
Cd3P2     cadmium phopshide   1214-28-7      Wrong checksum (correct: 4)
YBr3      yttrium bromide     13469-92-2     Wrong checksum (correct: 6)
YSb       yttrium antimonide  12186-97-7     Wrong checksum (correct: 9)
 Fixed All have now been corrected. -- Ed (Edgar181) 18:57, 14 December 2010 (UTC)[reply]

Redirects

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I think it would be useful to create a redirect to this page for each chemical formula listed here. That would help search engines find the page, and deal with the fact that most people won't use subscripts when entering search terms. -- Beland (talk) 17:35, 10 January 2009 (UTC)[reply]

chemical naming schemes

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It seems that multiple naming schemes are used. Shouldn't only one be used or list all common names for the chemical? For instance, the list has "silver flouride" (which I dabb'd to "silver(I) flouride"), but "silver(I) carbonate" instead of "silver carbonate". Either we should stick with one naming scheme, or list both when possible. Also, when the formula represents molecules with multiple forms, shouldn't all of those forms be listed? - UtherSRG (talk) 17:53, 20 April 2010 (UTC)    (Please reply on this page. I'll be watching it for a while.)[reply]

I agree on Silver(I) fluoride, as Silver(II) fluoride is an existable compound too, and as it links bleu, is in WEikipedia. On the other hand, old customs are hard to change. T.vanschaik (talk) 13:42, 19 June 2013 (UTC)[reply]

suggest merging with List_of_CAS_numbers_by_chemical_compound

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suggest merging with http://en.wikipedia.org/wiki/List_of_CAS_numbers_by_chemical_compound this and the other seems to be of simular content. some on that page are not on this page. eg, BiVO4 if i am in error provide a link between the two. if you want to go way further you can merge with (or provide a link to) http://en.wikipedia.org/wiki/List_of_inorganic_compounds and all its sister pages. there is a few too many lists on Wiki! Charlieb000 (talk) 23:08, 23 February 2012 (UTC)[reply]

The represent different chemical concepts, so I am not sure this is a good idea. What would the chemical formula of formalin be? --Egon Willighagen (talk) 07:44, 11 October 2020 (UTC)[reply]

sort by element

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i suggest a new page based on this (and my previous suggestion) where they are sorted by the elements they contain (it does exist but is not "complete" with these list items, so i leave this section here. http://en.wikipedia.org/wiki/Inorganic_compounds_by_element). then provide a link from the element page via "category: <element> compounds" this will be much more comprehensive than the current link which only shows compounds which have a page on wikipedia. a good alternative is one page (ONLY!) with a sortable wikitable, more info in above article's talk page. this ensures all elements are mentioned and user can select mode of viewing instead of the numerous tables we have already Charlieb000 (talk) 23:12, 23 February 2012 (UTC)[reply]

As most chemical compounds are categorized as a compound containing element, eg as Silver compounds and as Fluorides for Silver(II) fluoride, searching for compounds per element do not need a special additional ation. T.vanschaik (talk) 13:50, 19 June 2013 (UTC)[reply]

Organic compounds

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Please see discussion at Wikipedia_talk:WikiProject_Chemistry#List_of_organic_compounds about inclusion of organic compounds in this list. Biscuittin (talk) 12:34, 24 November 2014 (UTC)[reply]

The discussion is now archived at Wikipedia talk:WikiProject Chemistry/Archive 33#List of organic compounds.--Quest for Truth (talk) 20:52, 3 March 2016 (UTC)[reply]

Kudos

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To anyone who contributes to the never ending list

Rewriting order of elements in the compounds?

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For example, Lithium fluoride is listed as both LiF and FLi. Isn't it standard to list the cation first? I propose that we should remove all the listings that have the anion first and make sure they appear once with the cation first, or at least have the formula written out in the most common/consistent fashion (e.g. nitrosyl fluoride appears here once as FNO, but on its Wikipedia page it appears as NOF). Just a thought. Albatronix (talk) 00:57, 7 July 2018 (UTC)[reply]

Update: Actually in this example FNO may be more accurate because NOF makes it seem like the O is bonded to the F, which it isn't. Maybe it's okay... — Preceding unsigned comment added by Albatronix (talkcontribs) 01:01, 7 July 2018 (UTC)[reply]

I think sorting by cations (K+ in KCl, SIV in SF4, etc) or center atoms (S in CuSO4, etc) either is OK. --Leiem (talk) 05:41, 7 July 2018 (UTC)[reply]

Using extended sum formulas

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While different compounds with same sum formulas often have different ring, ring connecting bridge and side chain ramification counts extending the formulas with these 3 numbers would already drastically decrease the masses of compounds under same formulas to very few internal-permutation isomers so that categorization were vastly improved and sharpened. E.g. these 12 different structural isomers of C6H6 can be fully distinguished with those 3 additions extended behind C's count number:

C6, 2, 5, 1H6 Methyl-(2.2)Spiropentadiene CC1=CC12C=C2 2 cyclopropane rings (each –2) → 1+1, 2 ring internal double bonds + a spiro bond 2+2+1, 1 side chain
C6, 2, 7, 0H6 Bi(cyclopropene) C1=CC1C2C=C2 2+2+3 due to counting a non-fusing bond between rings as 3, a fusing methylen as 4, non-fusing methylen as 5 …
C6, 3, 4, 1H6 Fulvene, Methylenecyclopentadiene
C6, 3, 5, 0H6 (2.3)Spirohexadiene
C6, 4, 5, 0H6 Dehydrospirobicyclobutane C1=CC12C3C2C3
C6, 4, 6, 0H6 Benzene
C6, 5, 6, 0H6 Bicyclo[2.2.0 / 3.1.0]hexadiene (Dewar benzene) +1 from position 3 on → 2+2+1, 3+1+1
C6, 5, 8, 0H6 Bicyclo[2.1.1]hexadiene 2 internal double bonds + 1 fusing methylen → 2+2+4
C6, 6, 8, 0H6 1,1,2-Propellene, Tricyclo[2.1.1.01,4]hexene
C6, 7, 6, 0H6 Tricyclo[3.1.0.02,6]hexene, Benzvalene
C6, 8, 6, 0H6 Tetracyclo[3.1.0.01,4.02,4]hexane C12CC13C24C3C4 (4 trigons in a plane)
C6, 10, 6, 0H6 Prismane

Also e.g. the C6H10O4 would provide much more distinguish and recognition:

So this would give much more compound information quickly and a great gain for every sum formula compound glossary? --LKreissig (talk) 23:08, 21 April 2019 (UTC)[reply]

Formulas or Formulae?

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The proper plural form of formula should be formulae...? I'm Caker18! I edit Wikipedia sparingly. (talk) 05:27, 11 November 2019 (UTC)[reply]

Lists are largely redundant, I fail to understand why these are separate pages. Reywas92Talk 23:09, 1 February 2020 (UTC)[reply]

I just merged the unnecessary duplicate Inorganic compounds by element to List of inorganic compounds but now I fail to understand why this duplicate is necessary either. No need to filter out the organic compounds that mostly start with C anyway. (List of organic compounds was redirected here five years ago). Not sure if there's really anything in either case here to merge, but they've grown independently which is why you shouldn't be making duplicate articles in the first place... Reywas92Talk 23:16, 1 February 2020 (UTC)[reply]

Oppose - We should not mix organic and inorganic compounds. The organic compounds are already listed in 20 articles named List of compounds with carbon number 1 to 100. And listing the compounds after the formula isn't a good idea. If its done alphabetically it should CH and the rest of the letters alphabetic. Christian75 (talk) 20:51, 7 February 2020 (UTC)[reply]
Ummmm Glossary of chemical formulae already mixes organic and inorganic compounds... My point is that List of inorganic compounds is redundant to the glossary. What does "And listing the compounds after the formula isn't a good idea" mean? That's what all of these pages do; the glossary is a sortable list by either formula or name. Ugh this is why I do WP:BOLD merges, these pages are just duplicates of each other, just big and a lot of work. Reywas92Talk 21:22, 7 February 2020 (UTC)[reply]
No. Glossary of chemical formulae lists the formula by their chemical formula. List of inorganic compounds lists the comopund ordered by their central atom, e.g. HIO3 is in the former listed under H and in the latter under I. IMHO, you can redirect Glossary of chemical formulae wherever you want. Christian75 (talk) 01:17, 8 February 2020 (UTC)[reply]
Strongly Oppose I don't like you proposal.Huzaifa abedeen (talk) 04:24, 4 December 2020 (UTC)[reply]

Wrong formulas

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Some formulas listed here are wrong. For instance, that of goethite, written as "FeO2H" - is completely wrong. It does not show the role of H in this compound. Goethite is an example of oxyhydroxide - a well-known group of minerals. The correct formula is FeO(OH). The formula listed here is even wrong as compared to formulas written using well-known in chemistry alphabetical order, which would give HFeO2. Eudialytos (talk) 13:17, 15 November 2020 (UTC)[reply]

@Eudialytos: I'm sure that no-one will complain if you fix them; go ahead and BOLDly fix them. Klbrain (talk) 10:43, 9 January 2021 (UTC)[reply]

To be fair, these formulae are not wrong per se, just following different conventions. We could use empirical formulae, the Hill system or something else. The system used in this article seems to put the metal or main element first, hence FeO2H. This makes sense for an alphabetic list where you want all the iron compounds listed together under Fe. If you used HFeO2, it would unreasonably emphasise hydrogen over iron. What's harder to understand is sometimes grouping up hydroxides, e.g. Al(OH)3, and sometimes not, e.g. FeO2H. FeO(OH) might be seen as inconsistent with, for example, sodium hydroxide that is written NaOH rather than Na(OH). Another option is FeOOH, although that could imply iron(I) hydroperoxide, i.e. [Fe+][O-O-H], to some readers (even though most chemists would recognise that as an unlikely formulation. Personally I think FeO(OH) is best but this is not a completely clear-cut case. --Ben (talk) 14:33, 9 January 2021 (UTC)[reply]

Superheavy elements

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Can someone help me update this list? I've noticed a lot of superheavy elements missing. UB Blacephalon (talk) 03:33, 18 January 2021 (UTC)[reply]

Adding a new rule

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Can we make the list blue link only? Like the description says, "there is no complete list of chemical compounds since by nature." Shouldn't we only add notable compounds to this list. The best way for us to do that would be to only add chemicals with pages. If not, we could fill this list with millions non-notable molecules.Herravondure (talk) 03:04, 8 June 2022 (UTC)[reply]