By chem 2, you mean the second part of general chem? If so, then I can offer some advice:
What I mainly did for this course was do practice problems, practice problems, and more practice problems. This might just be common sense, but don't do the practice problems just for the sake of doing them. Think about what your doing and why your doing it. After a while, I felt that I did the problems just to do them, and that doesn't help at all.
Also, I found that flash cards helped, but flash cards are not really specific to chem 2 because I find that writing things down helps me remember things in any subject.