Suppose I've discovered something that I think will be useful for others. But I don't have a question, I just want to share it. Can I post that on Chemistry Stack Exchange? Do I have to do it in a "question-and-answer" format, even if I never had an actual question?

The specific thing I found was that there are several "pH value calculator" widgets available online, and virtually all of them (8 out of 9) give the wrong answer when calculating the pH of an $\ce{H2SO4}$ solution. This is because they all assume that sulfuric acid donates only the first proton, but they don't take into account that it's a polyprotic acid and that some of the molecules donate a second proton as well. So they tend to give higher than correct pH values (that is, underestimate the number of protons in solution).

Here are the ones I found. For all of them, if you attempt to calculate the pH of an $\ce{H2SO4}$ solution at $\pu{0.001 M}$, they give the answer as $3$, although the answer from reference is $2.75$:

and, drum roll, the only one that got it right:

  • $\begingroup$ You can use meta for this but I think it will be off topic on the main site. $\endgroup$ May 28, 2018 at 23:51
  • $\begingroup$ I don't understand how it's on topic for meta but off topic for the main site, at least based on the descriptions of the sites that appear in the sidebar when you're posting a question. Meta is supposed to be about Chemistry Stack Exchange; this wouldn't be a post about Chemistry Stack Exchange, it's just a post about chemistry. $\endgroup$
    – Bennett
    May 29, 2018 at 0:17
  • 7
    $\begingroup$ Nah, this isn't a meta thing. If you want to merely share it with an audience, you can do it in chat. The SE chats' transcripts are kept around forever, but it's a much smaller audience than the potential viewers of a question. You could try fitting it into a question that you yourself answer, but there's little possibility to do that in this case. $\endgroup$
    – M.A.R.
    May 29, 2018 at 0:30
  • $\begingroup$ @M.A.R.ಠ_ಠ ok thanks. That does seem like a limitation in the system -- people come to the site for useful information, and sometimes that's in the form of a question & answer, but sometimes it's also in the form of just an informative post, so it's unfortunate if there's no built-in way to just make an "informative post." But, again, that's something I should suggest on Meta Stack Exchange... $\endgroup$
    – Bennett
    May 29, 2018 at 18:38
  • 1
    $\begingroup$ SE was never meant to cover all the useful information about a subject. Instead, they aimed to specialize at a specific type of information exchange (no chit-chat etc. -- Imagine a couple of busy and professional programmers and one runs into a question about a line of code). We can either be good at collecting all kinds of information, or great at collecting a specific subset. SE chose the latter, and there are other mediums for other types. $\endgroup$
    – M.A.R.
    May 29, 2018 at 21:48
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    $\begingroup$ S.E adds a bottomline before you post a question -- "Answer your own question – share your knowledge, Q&A-style" $\endgroup$ Jun 16, 2018 at 19:23
  • $\begingroup$ @Rahul I saw that, and that's one of the possibilities I asked about, but M.A.R. said above for some reason that "there's little possibility to do that in this case" so I figured someone with more experience on the site would know better. $\endgroup$
    – Bennett
    Jun 17, 2018 at 6:19

1 Answer 1


That is essentially what self-answers are for.

The Stack Exchange model allows you to immediately add an answer to your question and post those two together. This is the preferred way to pass on knowledge.

However, Stack Exchange remains a Q&A site, so all such knowledge passers must fit the question-and-answer model.

If you want an example, please see my self-answered question on point groups on the main site.


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