Amazing teacher. Very manageable workload as long as you don't wait until the last minute to do homework assignments. You do have to pay for the textbook, since he uses Cengage. And 50% of our grade is based on homework and attendance, which are both very easy to get 100% on. Overall, a great teacher and I would definitely take him again if I could.

Deifel was incredibly welcoming, helpful, and an overall fun and engaging lecturer. The class is mostly based on participation - the majority of your grade comes from going to discussions, completing the homework (you have 10 attempts per question, and if you get the question wrong it shows you how to do it), and showing up to class (he tried to use iClicker but it didn't end up working out). The tests and midterms are over exactly what he says he will cover - you understand what you need to study. Deifel also offers tons of office hours where he explains so many concepts and helps answer specific questions from the homework. He truly cares about his students and wants to see them succeed. I highly recommend taking this class.

Dr. Deifel is one of the best teachers I've ever had, and he's made chemistry so much more enjoyable for me. Though the course isn't exactly easy, it's not too difficult to get an A in this class. He provides all the resources necessary for you to succeed. It's very clear how much he loves the subject and how much he loves teaching. 10/10 would take again.

Deifel is such an enthusiastic teacher. He brought so much energy to our 8 AM that I think he genuinely improved students’ moods. He really cares about his students, and it shows. 100% a teacher I bragged about to my friends. Attend his office hours; you won’t regret it.
The content can seem kind of overwhelming at first but he explains a lot, gives a lot of points for homework and participation, and his tests are absolutely fair and manageable.
I think the only complaint I heard was the homework program, but he hates it too so you end up bonding over it (don’t worry, it’s actually set up to get you a 100% on hw- it’s just annoying).
Anyways, I really liked him as a teacher and would love to have a class of his again. Definitely recommend.

Deifel is a a great professor. He's a little goofy but super helpful professor and has lots of office hours. He is genuinely rooting for everyone's success and really tries to make lectures engaging and fun. Even though it was an 8am, CHEM 20A is one of my favorite classes I had this quarter.

The content of the class was very difficult for me but in his review sessions, he goes over exactly what is going to be in the midterm and finals. Would highly recommend! He may be homeless(?) and divorced but he really loves chemistry.

Professor Deifel is easily one of the most caring professors at UCLA. He takes the time to learn each of his students' names, and he makes himself available even late during the night to help students. He is not only passionate about chemistry, but he is passionate about making sure that all of his students succeed. In terms of grading, Deifel made it very easy to earn an "A." Half of your grade is determined by homework (based on completion, not homework) and attending discussions. The other half is based on the final and two midterms, which are pretty reasonable in difficulty. Overall, I'd 100% recommend taking this class with Deifel!

Diefel is exceptionally enthusiastic and it is apparent that he is passionate about what he teaches and genuinely cares for all of the students. He's pretty humorous, which made his lectures engaging and enjoyable. I found the materials covered in this class to be pretty tough, but this has more to do with the nature of the subject, and Diefel does his best to make the best out of the experience. 50% of the grade comes from homework and attendance, and while the homework on the Owl can be convoluted and not always relevant, it is easy to get 100% on them. His midterms are fair and he always hold a review session before each. Overall, his class was one of the most enjoyable that I have taken in a long time and I would definitely recommend and gladly take again.

One of the best professors I've ever had. Very knowledgable in chemistry and has genuine care for all his students. Midterms are fair (not too hard, not too easy), and if you are ever struggling with a concept, Professor Deifel holds office hours throughout the week and is very responsive. He does an excellent job preparing students for the next class in the Chem 20 series. Would 100% recommend taking his class.

Professor Deifel makes chemistry at 8:00 AM not only bearable but actually enjoyable. Homework and participation account for like 50% of your grade, both of which are easy to get full credit on. The midterms are fair and he gives a detailed review session telling you exactly what to expect. He is always willing to hold office hours and is incredibly responsive to messages. Overall, you can tell that Professor Deifel is quite devoted to the field of chemistry and his students, making his Chem 20A worth taking.

Very engaging lectures and a great teacher. Has helpful reviews before the tests and lots of office hours for extra help. Cares about students learning and provides many resources. I don’t like chemistry much but found this to be one of my favorite classes.