Chemistry Naming: C First in CO2? H2O OH2?

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Discussion Overview

The discussion revolves around the naming conventions of chemical compounds, specifically why certain elements are placed first in formulas like CO2 and H2O. Participants explore the underlying principles that dictate these conventions, including electronegativity and periodic trends.

Discussion Character

  • Conceptual clarification
  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant questions why carbon is placed first in CO2 instead of oxygen, suggesting a lack of clarity in naming conventions.
  • Another participant speculates that chemical formulas may follow an alphabetical order, though they are unsure of the language influence.
  • A different participant proposes that the naming convention is based on the "core atom," defined by the lowest electronegativity, using CO2 as an example.
  • Another contribution mentions a periodic trend where more metallic elements are placed first, citing examples like NaCl and HCl, while acknowledging exceptions like CH4.
  • One participant expresses a desire for input from a chemist to clarify the theories discussed.
  • A participant states that the electropositive constituent should be placed first in binary compounds, referencing a specific sequence of elements that follows established practice.
  • Another participant notes that while simple molecules follow these rules, more complex organic compounds have a complicated hierarchy for naming, which can involve assigning points to atoms for configuration determination.

Areas of Agreement / Disagreement

Participants present multiple competing views on the naming conventions, with no consensus reached regarding the primary factors that determine the order of elements in chemical formulas.

Contextual Notes

There are unresolved aspects regarding the influence of electronegativity versus periodic trends, and the complexity of naming conventions in organic chemistry is acknowledged but not fully explored.

Who May Find This Useful

This discussion may be of interest to students of chemistry, educators, and anyone curious about chemical nomenclature and the principles behind it.

mrzero
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Hi I have a lame question about the naming of chemicals . If we get a combination of 2 chemicals like CO2 why is the C in the first place ? Why isn’t CO2 named O2C ? H2O is another example why not OH2 ? what determines the proper naming of chemicals thanks for the futer answers.
 
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I'm not a chemist but just thinking about all of the chemical formulas I'm familiar with it seems like they're in alphabetical order.

The alphabet of which language, I couldn't tell you. I would've thought Latin or Greek or something like that.
 
I believe that the convention of simple molecules such as CO2 and H2O are based on the "core atom" or the one with the lowest electro negativity.

eg in CO2 the electronegativity of C is = 2.5
O is = 3.5
 
It's a periodic Trend for the more metallic element to be placed first.

Or, the further to the left it is.

It's always NaCl

HCL

FrF

Whatever, that is a the basic rule, there are one or two exceptions such at Methan CH4, but that is simply because there are 4 hydrogens, but as a simple rule it seems to work well.
 
O bump

I never asked a chemist this question maybe one will eventually come here. We have some theories here maybe somebody explain it and be a teacher or phd or professor or something ?
 
The electropositive constituent (cation) should always be placed first. In the case of binary compounds between nonmetals, the constituent that should be placed first is the one which appears earlier in the sequence: Rn, Xe, Kr, B, Si, C, Sb, As, P, N, H, Te, Se, S, At, I, Br, Cl, O, F. The latter is in accordance with established practice.
 
What chemisttree said holds for most all simple molecules you could write a formula for. As they get more complicated, especially with organic ones, there's an extensive hierarchy of what goes first, how atoms are grouped together, and what name the compound has by IUPAC standards.

Which can get *really* complicated once you get deep into organic molecules, to the point where you have a method where you assign points to each atom in a molecule to decide whether the molecule has a 'clockwise' or 'anti-clockwise' configuration...
 

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