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:
|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.