A lot of people have recommended Chad's videos for the Gen Chem. I tried them out since I was feeling fuzzy on the gchem section too and now I feel like gchem is one of my strengths. They have really helped me a lot!
Gen chem was my worst subject as well i used kaplan and chads videos to understand the concepts then did kaplan subject tests and destroyer those are the best resources and then u get an idea of knowing just how many different problems there are and you should be fine best of luck to everyone!
I made a 24 in GC, but I tutored it at a CC for 4 years. I took the DAT twice, one time I made a 16 (LOL) and the second I made my 24. That tells you how random the test is, because I didn't study any more for the second one.
What I suggest: Make yourself an outline of all the GC subject matter. Go through and study the stuff you DO NOT know the most (80% of the time). Use the other 20% to review the stuff you have pretty good control of.