This has really been troubling me for quite a long time now. I don't have the relevant literature to confirm whether writing "hydrogens" is correct or "hydrogen atoms" is (for the same matter, "oxygens" vs "oxygen atoms", etc.).

According to me, "hydrogen" refers to the element hydrogen. Thus, "hydrogens" refers to elements of hydrogen OR element hydrogens, which makes no sense to me. In this context, "hydrogen atoms" does indeed make sense, as it refers to atoms of the element hydrogen.

Which one of them is the correct description?

An interesting statistic: 641 distinct posts on Chem.SE mention "hydrogens", vs 515 distinct posts mentioning "hydrogen atoms".

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    $\begingroup$ I really think both are fine and most likely clear from context. $\endgroup$ Commented Feb 27, 2018 at 12:54
  • $\begingroup$ @Martin-γƒžγƒΌγƒγƒ³ Yes, me too! :) Though the "hydrogens" does feel weird to me sometimes. $\endgroup$ Commented Feb 27, 2018 at 13:08
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    $\begingroup$ Every chemistry professor I've encountered, with whom this conversation has arisen, has preferred "hydrogen atoms." $\endgroup$
    – Zhe
    Commented Feb 27, 2018 at 13:47
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    $\begingroup$ There may be a split between written and spoken usage. When speaking we often use shortcuts (dropping the 'atoms') that we might not when writing, particularly in formal contexts. $\endgroup$
    – Jon Custer
    Commented Feb 27, 2018 at 15:39
  • $\begingroup$ @Zhe I had one particular professor who strongly rejected "hydrogen atoms" or using "atoms" in general, when talking about a molecule, because they are no longer atoms so h{is..er} argument. $\endgroup$ Commented Mar 1, 2018 at 5:33

1 Answer 1


I would say this is just a case of formal vs. informal speech. I teach chemistry for a living and I would never write "hydrogens" or "carbons" but I can guarantee you that I have said "hydgrogens" and "carbons" many times while referring Lewis structures or concepts related to NMR, etc. in class or office hours. While it may look a little ugly on the written page, it's unambiguous and quickly communicates the intended meaning.


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