Where are guidelines about proper text formatting, suggested edits, and their review? Possibly there is nothing but “common sense”, but Ī̲ don’t hold in respect sites where users are encouraged to assess things they’re unwilling to read carefully, such as this.
No such specific guidelines exist on this site, though the community here tends to reject 'cosmetic' edits unless they are substantive and/or drastically increase the quality of the question/answer.
In the odd case where edits have been disagreed over and one or both parties are unsatisfied with the result they have brought the question here to ask the community their opinion, which generally resolves the problems.
If you want to discuss the specific edit you mentioned being rejected and ask for wider consensus or reasons why it might have been rejected, then I would suggest raising a question specifically about that edit on the meta, and posting the link as a comment on the question; something along the lines of "This question/answer is currently being discussed on meta <link>". Raising things in this way tends to be standard practice on this site.
There are no specific guidelines, but I'll give my opinion on cosmetic edits.
People use the close reason unclear what you're asking for certain reasons but to me a question can be unclear because of how badly formatted the question is.
Zero line breaks, superfluous whitespace, unnecessary phrases such as salutations or apologies (such as for perceived sub-par English speaking skills) or thanks, poor grammar/spelling, or any sort of dramatic flair such as "I need help!" and what not.
I will edit and I tend to accept edits that improve the question's appearance. However, I only do so when I know that it hasn't met any of the edit rejection reasons. If it "conflicts with the author's intent" or offers no improvement (or makes it worse) then I'll reject it, because that's a valid rejection reason for any sort of edit.
That being said...
In your example, you changed - to – everywhere, and made edits like LH2 to LH2. I'm not well versed in Chemistry rules, but I looked up liquid hydrogen and found that it can be LH2 or LH2.
To me, that's an unnecessary edit. It was also difficult to read what your edit was supposed to achieve, but when I looked at the actual post, it seemed rather readable to me. In your reason for editing, your comment was "typography (mostly removal of inappropriate italic)." In another edit of yours that I found, your edit comment was "rectified “\cos 60” rubbish, other fixes."
Words like inappropriate and rubbish seems to me to violate the Be Nice principle that the Stack Exchange networks tend to adhere to, and it offers up no information that would help someone understand what your edit was supposed to achieve.
If you truly feel like your edit is a strong improvement, I'd recommend that you use the comment to convey that improvement more if it's possible that it could be confusing to a reviewer. In the event of conflict or if you have a question about it, follow the advice @Mourdos provided in his answer.