as a chem grad, I'll second Dk-blue_Falcon's professor recommendations. just two things to add:
1. Tina Johnson is a good professor for any class in the series, period. She also teaches 6C occasionally.
2. If you can't score Kummel for 6B, go with Crowell. I never took any notes in his class, but all his exam questions have been repeated for so long that his practice exams are the exact same thing as the real ones. My TA used his old exams to prep us during discussion section, it helped immensely
