try to take an objective look at how many hours per week and how well you are actually studying; most people think they are studying alot but really aren't. With chemistry and pretty much all of my studying I did 40 mins studying(zero distractions), 10 min phone break. Gen chem is all about understanding/manipulating formulas and exposure to problems. There is only a handful of ways they can ask problems per topic. watch videos to understand topics then 40-50 minimum practice problems per topic for exams the week before an exam. don't look up problems until you got an answer and if you're wrong know why and add more practice problems. This is all you need and how I got A's in chem and tutor students to get A's.