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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. Wikipedia 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. [[Special:Contributions/209.6.225.254|209.6.225.254]] ([[User talk: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/wiki/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 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. [[User:EnderLender|EnderLender]] ([[User talk:EnderLender|talk]]) 17:47, 27 October 2024 (UTC)

== Hill order ==

Following the rules of the Hill system, <code>BrClH<sub>2</sub>Si</code> should be sorted before <code>BrI</code>, because <code>Cl &#x3C; I</code>. The priority of single-letter over two-letter symbols only applies to the same letter (<code>C &#x3C; Cl</code>, <code>I &#x3C; In</code>). This can be confirmed since Hill's [https://zenodo.org/records/1428916 original publication] sorts <code>CCuN … &#x3C; ClCu … &#x3C; KMnO<sub>4</sub></code>. [[User:Aerilius|Aerilius]] ([[User talk:Aerilius|talk]]) 19:00, 2 January 2024 (UTC)
:{{fixed}} Thanks for catching that! [[User:DMacks|DMacks]] ([[User talk:DMacks|talk]]) 19:40, 2 January 2024 (UTC)

== Semi-protected edit request on 26 July 2024 ==

{{edit semi-protected|Chemical formula|answered=yes}}
 [[Special:Contributions/45.124.6.19|45.124.6.19]] ([[User talk: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
:[[File:Red question icon with gradient background.svg|20px|link=|alt=]] '''Not done:''' it's not clear what changes you want to be made. Please mention the specific changes in a [[WP:EDITXY|"change X to Y" format]] and provide a [[Wikipedia:Reliable sources|reliable source]] if appropriate.<!-- Template:ESp --> [[User:HeartGlow30797|'''<span style="color:red; text-shadow:#ffdf00 0.0em 0.0em 2.0em">Heart</span>''']] <sup><small>[[User talk:HeartGlow30797|''(talk)'']]</small></sup> 16:42, 26 July 2024 (UTC)