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(C6H5)3PBr2 | |||
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I'm missing mentioning of other (more advanced) ways of describing chemicals, such as ], or visual representations, as for example ] (how do you actually call these diagrams?). --] 17:06, 6 December 2005 (UTC) | |||
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: Those are usually called "structure diagrams". ] 23:55, 2 January 2006 (UTC) | |||
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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. | |||
== Question == | |||
What does a formula such as FeS<sub>2-x</sub> mean? Can this be included in the article? | |||
:See ]. Yes, I think it should be mentioned in the article. ] 16:07, 9 February 2006 (UTC) | |||
:: Thanks ;) | |||
]Ô | |||
== chemical compounds == | |||
Do the groups of chemical equations Ch3OCH3, Ca3(PO4)2,CO2,H2CO3 contain entirely of organic compounds? | |||
:No. ] 16:06, 4 May 2006 (UTC) | |||
== chemical/molecular/empirical formula == | == chemical/molecular/empirical formula == | ||
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So who is right? | So who is right? | ||
== Electronegativity-based alternative to Hill system ordering == | |||
== naming elements in formulae? == | |||
how are chemical formulae read in english? for example, water is , and what about iron - or ? | |||
I studied chemistry, and I definitely learned the Hill system: First carbon, then hydrogen, then all other elements in alphabetical order. However, I was taught (and I often observe) a slightly different system. Like Hill, it begins with carbon then hydrogen. Unlike Hill, all other elements are in order of electronegativity, with fluorine last. This gives the familiar H2SO4, whereas Hill gives the far less common H2O4S. Misplaced Pages itself often favors this electronegativity-based system, as can be seen in halogenated compounds where Br and Cl appear at the very end, despite coming early in the alphabet. I think Hill is favored when electronegativity is not so obvious. On a related note, ionic compounds generally get the cation first, which obeys the electronegativity order but overrides the precedence of C and H, giving familiar ionic compounds like NaCl, NaOCl (which is not in Hill order), HCl (not Hill order because it lacks carbon but H precedes Cl), and NaHCO3 (sodium bicarbonate, showing that C loses primacy in an ionic compound). I don't know if there are names for these systems that use electronegativity to partially or fully override alphabetical order. They also seem less standardized than the Hill system, but quite common. ] (]) 11:03, 29 October 2023 (UTC) | |||
== Mystery Symbol== | |||
:Personally, I feel your point about naming cations first then anions in ionic compounds should be included in this article, however it is talked about here: https://en.wikipedia.org/IUPAC_nomenclature_of_inorganic_chemistry#Simple_ionic_compounds, maybe these two articles can be merged but I'm inexperienced with wikipedia so I dont know why it hasn't been merged already, maybe someone else can tell the reason. | |||
in a number of chemicle composition formulas, I've encountered a symbol before the equation | |||
:Your point with H<sub>2</sub>SO<sub>4</sub> is right according to me, here's a possible explanation as to why the name doesn't use hill system. First off why is H<sub>2</sub>SO<sub>4</sub> covalent? According to me people base it off of relative electronegativity values. If the relative electronegativity is small, compound is covalent. If the relative electronegativity is high, compound is ionic. Relative electronegativity is usually low if the atoms in the compound are non metals. In H<sub>2</sub>SO<sub>4</sub> all the atoms are non metals so H<sub>2</sub>SO<sub>4</sub> is covalent. I believe HCl is also covalent even though you said it is ionic because the atoms in HCl (hydrogen and chlorine) are nonmetals. It is easy to get confused on how to determine if a compound is ionic or covalent if you define ionic compounds to be compounds that exist as ions in a medium (cation and anion), you might think since HCl dissociates into H<sup>+</sup> and Cl<sup>-</sup> in water then HCl must be ionic, same can be said with H<sub>2</sub>SO<sub>4</sub> which dissociates into 2H<sup>+</sup> and SO4<sup>2-</sup>. This confusion might've led to the use of ionic naming of H<sub>2</sub>SO<sub>4</sub> and HCl, this is personally my view I don't have any sources to support this claim. Please do point out any mistakes I made. ] (]) 17:47, 27 October 2024 (UTC) | |||
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. | |||
== Hill order == | |||
e.g- Goethite: 'oc' - Fe<sup>+3</sup>O(OH) | |||
Following the rules of the Hill system, <code>BrClH<sub>2</sub>Si</code> should be sorted before <code>BrI</code>, because <code>Cl < I</code>. The priority of single-letter over two-letter symbols only applies to the same letter (<code>C < Cl</code>, <code>I < In</code>). This can be confirmed since Hill's sorts <code>CCuN … < ClCu … < KMnO<sub>4</sub></code>. ] (]) 19:00, 2 January 2024 (UTC) | |||
:Sounds like the "proportional to" sign (∝). Maybe it's used to indicate a non-exact formula representation (correct chemical formula, but actual ] or mineral form not completely represented), but I'm only hypothesizing here. ] 02:43, 3 January 2007 (UTC) | |||
:{{fixed}} Thanks for catching that! ] (]) 19:40, 2 January 2024 (UTC) | |||
== Semi-protected edit request on 26 July 2024 == | |||
==Order== | |||
In which order are elements in the chamical formula ordered? --] 12:32, 9 January 2007 (UTC) | |||
{{edit semi-protected|Chemical formula|answered=yes}} | |||
:There are many different conventions. One of them is the ], 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). ] 16:44, 9 January 2007 (UTC) | |||
] (]) 16:41, 26 July 2024 (UTC) | |||
Hbgk ugly didi tough occur used truth it junk icy tai do du eth tc ro us di hiii | |||
:] '''Not done:''' it's not clear what changes you want to be made. Please mention the specific changes in a ] and provide a ] if appropriate.<!-- Template:ESp --> ] <sup><small>]</small></sup> 16:42, 26 July 2024 (UTC) |
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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?
Electronegativity-based alternative to Hill system ordering
I studied chemistry, and I definitely learned the Hill system: First carbon, then hydrogen, then all other elements in alphabetical order. However, I was taught (and I often observe) a slightly different system. Like Hill, it begins with carbon then hydrogen. Unlike Hill, all other elements are in order of electronegativity, with fluorine last. This gives the familiar H2SO4, whereas Hill gives the far less common H2O4S. Misplaced Pages itself often favors this electronegativity-based system, as can be seen in halogenated compounds where Br and Cl appear at the very end, despite coming early in the alphabet. I think Hill is favored when electronegativity is not so obvious. On a related note, ionic compounds generally get the cation first, which obeys the electronegativity order but overrides the precedence of C and H, giving familiar ionic compounds like NaCl, NaOCl (which is not in Hill order), HCl (not Hill order because it lacks carbon but H precedes Cl), and NaHCO3 (sodium bicarbonate, showing that C loses primacy in an ionic compound). I don't know if there are names for these systems that use electronegativity to partially or fully override alphabetical order. They also seem less standardized than the Hill system, but quite common. 209.6.225.254 (talk) 11:03, 29 October 2023 (UTC)
- Personally, I feel your point about naming cations first then anions in ionic compounds should be included in this article, however it is talked about here: https://en.wikipedia.org/IUPAC_nomenclature_of_inorganic_chemistry#Simple_ionic_compounds, maybe these two articles can be merged but I'm inexperienced with wikipedia so I dont know why it hasn't been merged already, maybe someone else can tell the reason.
- Your point with H2SO4 is right according to me, here's a possible explanation as to why the name doesn't use hill system. First off why is H2SO4 covalent? According to me people base it off of relative electronegativity values. If the relative electronegativity is small, compound is covalent. If the relative electronegativity is high, compound is ionic. Relative electronegativity is usually low if the atoms in the compound are non metals. In H2SO4 all the atoms are non metals so H2SO4 is covalent. I believe HCl is also covalent even though you said it is ionic because the atoms in HCl (hydrogen and chlorine) are nonmetals. It is easy to get confused on how to determine if a compound is ionic or covalent if you define ionic compounds to be compounds that exist as ions in a medium (cation and anion), you might think since HCl dissociates into H and Cl in water then HCl must be ionic, same can be said with H2SO4 which dissociates into 2H and SO4. This confusion might've led to the use of ionic naming of H2SO4 and HCl, this is personally my view I don't have any sources to support this claim. Please do point out any mistakes I made. EnderLender (talk) 17:47, 27 October 2024 (UTC)
Hill order
Following the rules of the Hill system, BrClH2Si
should be sorted before BrI
, because Cl < I
. The priority of single-letter over two-letter symbols only applies to the same letter (C < Cl
, I < In
). This can be confirmed since Hill's original publication sorts CCuN … < ClCu … < KMnO4
. Aerilius (talk) 19:00, 2 January 2024 (UTC)
- Fixed Thanks for catching that! DMacks (talk) 19:40, 2 January 2024 (UTC)
Semi-protected edit request on 26 July 2024
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45.124.6.19 (talk) 16:41, 26 July 2024 (UTC)
Hbgk ugly didi tough occur used truth it junk icy tai do du eth tc ro us di hiii
- Not done: it's not clear what changes you want to be made. Please mention the specific changes in a "change X to Y" format and provide a reliable source if appropriate. Heart 16:42, 26 July 2024 (UTC)