Talk:Chemical formula

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[edit] Missing information

I'm missing mentioning of other (more advanced) ways of describing chemicals, such as IUPAC nomenclature, or visual representations, as for example Image:Flutamide.gif (how do you actually call these diagrams?). --Abdull 17:06, 6 December 2005 (UTC)

Those are usually called "structure diagrams". Itub 23:55, 2 January 2006 (UTC)


Ax2

  um.... i wanted to know how to a write a chemical formula for given elements correctly. i know about the ratio method but it doesnt work with non- metals and non - metals.

[edit] Question

What does a formula such as FeS2-x mean? Can this be included in the article?

See Non-stoichiometric compound. Yes, I think it should be mentioned in the article. Itub 16:07, 9 February 2006 (UTC)
Thanks ;)

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[edit] chemical compounds

Do the groups of chemical equations Ch3OCH3, Ca3(PO4)2,CO2,H2CO3 contain entirely of organic compounds?

No. DMacks 16:06, 4 May 2006 (UTC)

[edit] chemical/molecular/empirical formula

The article on Empirical Formula equates "chemical formula" with "empirical formula," and distinguishes "molecular formula"

The article on Chemical Formula equates "chemical formula" with "molecular formula" and distinguishes "empirical formula"

(There is no separate article on "Molecular Formula")

So who is right?

[edit] naming elements in formulae?

how are chemical formulae read in english? for example, water is [eich 2 oh], and what about iron - [fe] or [aien]?

Iron is just iron. for example, FeO is just iron two oxide. (It has to do with chemical nomenclature, also.) 75.5.10.153 23:08, 16 September 2007 (UTC)minidude09

[edit] Mystery Symbol

in a number of chemicle composition formulas, I've encountered a symbol before the equation that looks like the infinity symbol with half of the second loop sliced off, or an 'o' and a 'c' pushed together. I am wondering what exactly this symbol means in reference to the equation. I've not encountered it anywhere else before.

e.g- Goethite: 'oc' - Fe+3O(OH)

Sounds like the "proportional to" sign (∝). Maybe it's used to indicate a non-exact formula representation (correct chemical formula, but actual allotrope or mineral form not completely represented), but I'm only hypothesizing here. DMacks 02:43, 3 January 2007 (UTC)

[edit] Order

In which order are elements in the chamical formula ordered? --Artman40 12:32, 9 January 2007 (UTC)

There are many different conventions. One of them is the Hill system, which is basically alphabetical and which is useful when you have a long list of compounds that you want to sort (for an index, for example). In other cases people sometimes sort by electronegativity (for example, in salts and other binary compounds; it is more common to see NaCl than ClNa), and in others people write the formula in a way that suggests the structure of the compound (especially for small organic molecules, such as CH3OH). Itub 16:44, 9 January 2007 (UTC)
I think that there should be a section about that in the article. --Artman40 17:49, 10 January 2007 (UTC)

[edit] Other forms I see on the net...

I am uncertain how to read these formulas...

Thanks, CarpD 23:58, 23 October 2007 (UTC)

Brackets are customary to enclose a grouping which has an overall charge, as [B12H12]2-. Parentheses are customary to enclose a grouping which occurs more than once in the formula, as Fe(NO3)2. Also parentheses can be nested inside brackets, as [Co(NH3)6]3+

And @ means that the As is trapped inside the Ni12As20 cage, but not chemically bound to it. This notation became popular with the discovery of fullerene cages, which can trap atoms to form La@C60 for example.

These points could be included in the article. Dirac66 00:50, 24 October 2007 (UTC)

Thanks for the information. That helped a lot. But yeah, I think that would most definitely be in the article. Or, in this article, Structural formula? Thanks, Marasama (talk) 06:38, 22 November 2007 (UTC)

I have added both points to this article on 8 January 2008. Dirac66 (talk) 22:45, 13 January 2008 (UTC)

[edit] Homework help

determine some example of atoms in the followig formula nac1,

—Preceding unsigned comment added by 71.252.44.236 (talk)

This would be a question for Wikipedia:Reference desk/Science, but the Reference Desk wants students to do their own homework. -- Beland (talk) 16:17, 19 April 2008 (UTC)

[edit] R

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:Structural formula. -- Beland (talk) 16:14, 19 April 2008 (UTC)