User:Physchim62/Style guidelines

These guidelines have been put together by the WikiProject Chemicals to help editors improve the 1000 or so articles on Wikipedia which are about chemical compounds.

Title

There is a misconception among certain editors that the title of a chemical compound article must be the systematic name of the compound: this is not always the case.

General rule

From Wikipedia:Naming conventions:

"Generally, article naming should give priority to what the majority of English speakers would most easily recognize, with a reasonable minimum of ambiguity, while at the same time making linking to those articles easy and second nature."

IUPAC preferred name vs. Systematic name

IUPAC recommends ^[1] the use of non-systematic names for some organic compounds, and these recommendations should be followed in article titles. Examples:

Acetic acid	not	Ethanoic acid
Toluene	not	Methylbenzene
Lysine	not	2,6-Diaminohexanoic acid

Element names

Traditionally, the names of three elements have been spelt differently in US and British English. With the onset of computer searching of databases it became necessary to standardize these spellings as follows:^[2]

Aluminium	not	Aluminum
Sulfur	not	Sulphur
Caesium	not	Cesium

These international standard spellings should be used in all chemistry-related articles on English Wikipedia, even if they conflict with the other national spelling varieties used in the article.

Use of Stock nomenclature

Stock nomenclature for inorganic compounds is based on the indication of the oxidation number (as a roman numeral, in parentheses) of each of the major elements in the compound, e.g. iron(III) chloride. It is widely, if sometimes incorrectly, used on Wikipedia for the titles of articles about inorganic compounds. It is not obligatory, as there are other acceptable methods for naming these compounds, but it is often preferred as the most common non-ambiguous name for a substance. The following guidelines are based on current WikiBestPractice:

1. Only the cationic element (i.e. the element whose name appears unchanged in the compound name) is assigned its oxidation number. Except in rare cases (none at present), we do not assign the oxidation number in the anion: hence potassium permanganate not potassium manganate(VII), sodium hypochlorite not sodium chlorate(I).
2. There is no space between the end of the element name and the opening parenthesis: hence silver(I) fluoride not silver (I) fluoride. Note that this is an exception to the usual English style for parentheses.
3. It is not necessary to specify the oxidation number when there is no possibility of ambiguity in the compound title: hence sodium chloride not sodium(I) chloride.
4. Stock nomenclature should only be used for ionic compounds. Compounds with a substantial degree of covalancy should be named by stoichiometric nomenclature: hence titanium tetrachloride not titanium(IV) chloride.
5. Stock nomenclature should not be used for compounds with mixed or non-integral oxidation numbers: hence triiron tetraoxide not iron(II,III) oxide (in fact, this article is difficult to name and, as an exception, redirects to magnetite).

Drug-related articles

See also WikiProject Drugs
Where a compound has a WHO International Nonproprietary Name (INN), this should be used as the article title.

Prefixes

For technical reasons, it is not recommended to use non-numerical prefixes in article titles. This includes:

Positional identifiers	ortho-, meta-, para-, α-, β-, γ-
Stereochemical identifiers	cis-, trans-, (E)-, (Z)-
Chiral identifiers	(R)-, (S)-, D-, L-, (+)-, (−)-

Note that iso in such compounds as isopropanol is not only permitted but recommended. No hyphen is used in these cases.

When the chosen aticle title starts with a number, the first letter of the compound name should be capitalized: hence 1,1,1-Trichloroethane not 1,1,1-trichloroethane. A redirect from the uncapitalized version should be created to simplify linking from other articles. See also Capitalization below.

Redirects

From Wikipedia:Deletion policy: "Don't worry, redirects are cheap."

Redirects should be created for:

• Alternative names for the compound, including acronyms where appropriate;
• Alternative capitalizations, where there is a numerical prefix in the article title.

Article format

Infobox

Wikipedia:WikiProject Chemicals strongly recommends the use of chemical infoboxes for the following reasons:

• If basic (often numerical) data is included in the article text, the readability of the article is reduced.
• They reflect a certain consensus as to what data is appropriate for an encyclopedic article.
• They promote a common visual style among Wikipedia articles on a given subject area.
• They are well supported by the MediaWiki software (unlike HTML tables), and easily adapted (by individual editors) to the different needs of different articles.

Three chemboxes are currently available:

• {{chembox simple inorganic}} and {{chembox simple organic}} are good for short articles (stubs and slightly-more-than-stubs);
• {{chembox}} is more appropriate for full-length articles.

To include a chembox in an article:

1. Edit the article to include {{subst:chembox}} (or {{subst:chembox simple inorganic}} or {{subst:chembox simple organic}}, as appropriate) as the first line of the article source code.
2. Save your edit with the Edit summary "Chembox added".
3. Re-edit the article to fill in the spaces in the infobox, and to make whatever other changes are necessary for the particular compound.

For formatting reasons, the code for the infobox should be at the very beginning of the source code.

Safety

The hazards associated with a chemical compound are an integral part of the description of that compound.

Two main rules:

• The description of hazards should avoid speculation. This is partly an extension of Wikipedia NPOV policy, but not entirely. There is no need to include a section which merely states "all chemical compounds should be treated with the utmost precaution": such a section tells the reader nothing. If there are no known (or reasonably suspected) hazards, there is nothing for Wikipedia to say.
• The description of hazards should avoid hyperbole. The role of Wikipedia is to give balanced and accurate information, to allow its readers to reach their own conclusions.

Descriptions of hazards should, as far as possible, be based on published, peer-reviewed sources (which should, of course, be cited at the appropriate point in the article). A list of resources for chemical safety information is given in the external links section of these guidelines.

References

See: Wikipedia:Footnote3, Wikipedia:Cite your sources

Other topics

Chemical structures and reaction schemes

From Wikipedia talk:WikiProject Chemicals:
This is the procedure I currently use for my images:

ChemDraw molecule editor settings:

• Line width: 0.107 cm
• Bond length: 2.566 cm
• Font: Arial 45 pt
• Save as: TIFF black/white bitmap.

Image processing (Photoshop or Irfan view):

• Add canvas of 75 pixels to all four sides (Photoshop: Image:Canvas Size, relative, 150 pixels width, 150 pixels height)
• Save as a PNG black/white bitmap.

Wikimedia Commons:

• Upload under http://commons.wikimedia.org/wiki/Special:Upload (bookmark address)
• Paste the summary template from below.
• Add the substance's article link to en.wikipedia, the user name, and the date.

Linking:

• As if it were uploaded to en.wikipedia.
• Add the horizontal image size "|200px|" (no frame) or "|thumb|200px|" (frame) to the image link:

[[Image:Ethylene glycol chemical structure.png|thumb|150px|Chemical structure of ethylene glycol]]

Wikimedia Commons summary template:

---

* Description: Chemical structure of [[w:|]].

* Author, date of creation: selfmade by [[w:User_talk:|]], 11 April 2005.

* Source: -

* Copyright: [[w:GNU Free Documentation License|GNU Free Documentation License]]. (GFDL)

* Comments: high-resolution b/w PNG; ChemDraw / Photoshop.

{{GFDL}}

[[Category:Chemical structures]]

---

Cacycle 15:11, 11 Apr 2005 (UTC)

References

1. ^ Panico, R.; & Powell, W. H. (Eds.) (1994). A Guide to IUPAC Nomenclature of Organic Compounds 1993. Oxford: Blackwell Science. ISBN 0-6320-3488-2.{{cite book}}: CS1 maint: multiple names: authors list (link)
2. ^ Leigh, G. J. (Ed.) (1990). Nomenclature of Inorganic Chemistry. Recommendations 1990. Oxford: Blackwell Science. ISBN 0-6320-2494-1.

External links

Nomenclature

• IUPAC Provisional Recommendations for the Nomenclature of Inorganic Chemistry (2004)
• IUPAC Nomenclature of Organic Chemistry (online version of the "Blue Book")
• IUPAC Recommendations on Organic & Biochemical Nomenclature, Symbols, Terminology, etc. (includes IUBMB Recommendations for biochemistry)

Properties

• WebElements
• NIST Standard Reference Database

Safety information

• International Chemical Safety Cards
• Concise International Chemical Assessment Documents
• IARC Monographs Database
• OSHA (US)
• OSHA Permissible Exposure Limits site
• NIOSH Pocket Guide to Chemical Hazards
• NIOSH IDLH site
• EPA AEGL (US)
• CDC Emergency Preparedness & Response (US)
• NTP Report on Carcinogens (11th Edn.)
• European Chemicals Bureau
• HSE (UK)
• CSST (Canada)
• NICNAS Reports (Australia)
• Institut national de recherche et de sécurité (France) (in French)

Suppliers

• Sigma-Aldrich Co.