If we look at the questions on the Chemistry site, what would a physical chemistry FAQ look like? Because the site tries to avoid duplicates, frequently asked does not mean frequently posted. Ideally, someone asking a frequent question would find a good answer on StackExchange without having to post it. I wondered if views of a question or the question score (or some combination) would be a good proxy for frequently asked (but not posted) questions.

Here is the SEDE query I used:

-- Find "popular" questions with a given tag
SELECT Posts.Id as [Id], Posts.Tags as [Tags], Posts.Score, Posts.ViewCount, Posts.CreationDate, Posts.Title
FROM  Posts
    INNER JOIN PostTags ON Posts.Id          = PostTags.PostId
    INNER JOIN Tags     ON PostTags.TagId    = Tags.id
WHERE Tags.TagName      = '##TagName##'
      AND Posts.AnswerCount > 0
      AND Posts.PostTypeId  = 1                -- PostTypeId = 1 -> Question
      AND Posts.CommunityOwnedDate is null
      AND Posts.ClosedDate         is null
      AND Posts.ViewCount > 1000
      AND Posts.Score > 2
      AND (Posts.ViewCount/100000.0 * Posts.Score * Posts.Score > 1.0)
ORDER by Posts.ViewCount      DESC;

The last line in the "WHERE" statement is an attempt to include questions with exceptionally high view count, or exceptionally high score while rejecting questions that are on the lower end of both of these criteria.

Here are some of the top questions in physical chemistry according to these two criteria, ordered by the combined score and view criterion:

Score ViewCount Title
181 166238 Can an atom have more than 8 valence electrons? If not, why is 8 the limit?
59 578831 Positive or Negative Anode/Cathode in Electrolytic/Galvanic Cell
35 1194707 What are the maximum number of electrons in each shell?
54 376105 Why is it important to use a salt bridge in a voltaic cell? Can a wire be used?
120 29012 Why is absolute zero unattainable?
34 177635 What would be the effect of the addition of an inert gas to a reaction at equilibrium?
26 246602 Why do branched chain compounds have lower boiling points than the corresponding
33 136091 What are angular and radial nodes?
32 57200 Why are solids and liquids not included in the equilibrium constant? What about in a reaction rate calculation?
30 54972 What is the unit of pH?

I suspect most of these questions come up when students take their first year of chemistry, so they probably don't reflect frequently asked questions while taking a physical chemistry course.

  • $\begingroup$ What makes you consider the aspect of "not frequently posted" at all? How is this relevant? Is it not good enough to equate the popularity of a post based on views and votes with how much people are looking up that question? $\endgroup$
    – Buck Thorn Mod
    Jan 12 at 18:42
  • $\begingroup$ @BuckThorn Sorry, my writing was probably unclear. I'm just saying that in other contexts, frequently asked makes sense (like in the class room), whereas on StackExchange, frequently viewed or high scores make sense. $\endgroup$
    – Karsten Mod
    Jan 12 at 18:59
  • $\begingroup$ Yes, the views count would be the equivalent of how often something is "asked", although it often fails when questions are subtle or complex and search engines just pick the most similar and popular post (delivering more views to that unhelpful post). Popularity breeds popularity. There are surely perfectly useless posts that have gotten tons of views. Usefulness and views need not match for one particular individual search, but obviously a post that gets more views has a better chance of helping people. $\endgroup$
    – Buck Thorn Mod
    Jan 12 at 19:11
  • $\begingroup$ The posts in your list are surely an accurate reflection of what is being searched for. It could include some students in pchem in a fix to understand or needing to review basic concepts. In any case, it's a good idea to make sure that the most viewed posts are of high quality. Your question is a good reminder of that. Post quality including formatting and spelling is something former mod Melanie among others have emphasized as important to attract views. $\endgroup$
    – Buck Thorn Mod
    Jan 12 at 19:13

1 Answer 1


Curiously, Stack Exchange's own search utility produces a different ranking:

enter image description here

It's not clear what is meant by "most frequent" but evidently it isn't the number of views.


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .