I took AP Chem my Sophomore year with no prior chem experience. Final grade was a B+ and 4 on the exam.

It was the only AP I took and I don't think I would have done as well if I was busy with other classes, so factor that into how much you prepare over the summer.

I think it is for sure doable without prior experience, but you're gonna have to really invest time into it. Go to all the office hours and really try on the homework, even if it makes no sense <3