TLDR: The class is a ton of work, but if you're planning on a career or major in science, it's completely worth it. You'll learn general chemistry principles like in 20B, albeit with a bit deeper understanding, and parallel to that you'll become literate at reading current scientific research. Also, if you want to do research as an undergrad, Paul is your guy and WILL hook you up with a position.

Compared to Chem 20B, this class is about 3-4 times as much work. In addition to the weekly homework assignment (problems from the textbook), Paul assigns weekly "creative problems," where we create and solve problems related to the current course material, and we have 5-6 literature assignments, which have us write reports on research articles published within the past year. In addition to a final exam you'll be assigned a lengthy final project, where you detail some current research area with a 5-10 page paper, presentation, and poster. And lastly, Paul assigns an "auxiliary assignment" each quarter, which are about the same amount of work as a syllabus assignment (but you can do multiple for extra credit). Sometimes it could be pretty nauseating doing the sheer amount of work that is assigned, but it is possible to do it if you don't procrastinate.

The class teaches the general chemistry principles that 20B does. Stuff like molecular bonding, electrochemistry, nuclear chemistry etc. But Paul puts special emphasis on adding in research-oriented content in his lectures. By that I mean he often teaches you about the experimental setups necessary to discover all the principles we learn about. This includes all the different types of mass spectrometry available, the different types of ways to "fingerprint" an atom/molecule, and flow cytometry. He cares that you learn more about the guiding principles and how to derive specific points of knowledge rather than memorize them (Like being able to tell him how to find an atomic radius rather than memorizing it for a couple atoms).

One con of the class is just how much background knowledge Paul assumes everyone has. Sure there's the tryhards who did research in high school, but fo someone coming out of AP Chem or Chem20A/AH, the first couple weeks it is VERY tough to follow along with Paul as he dives into anecdotes about his colleagues' research.

All in all, the class is extremely daunting if you don't have a very solid foundation in chemistry or don't plan on majoring in biology/biochem. However, it is definitely possible to adjust to Paul's pacing, and after a week or two you'll get a much better grasp at what the hell he's talking about. By the end (with enough effort), you can consider yourself relatively scientifically literate. If that's a goal of yours, this class is definitely worth the time, but I would recommend making sure all your other classes are easy.

MK. This is gonna be a long one.

This class is kinda wild and I'm still not sure if I should've taken it. I feel like it should probably be an 8 unit class or called Chem 20BHW or something because I literally wrote more in this class than in any other humanities class that I've taken here so far.

There are tons of pros of taking this class. First and foremost, if you want to get into a lab and are not really sure how- Paul will get you into one probably guaranteed. When you're sending out inquiries you can cc him and he'll vouch for your ability which can help. However, it's not completely necessary since I didn't cc him and still got into one of my top choice labs, so I'm kinda wondering if the rest of the class was worth it. Again though, if you're worried about it he will definitely help you be more knowledgeable about the research all the faculty does and will help you narrow down, so it's worth it in that regard.

You learn a lot but it's more intuition and scientific methods rather than actual chemistry as I studied very little and relied heavily on my AP Chem knowledge to do well in the class. The tests weren't too bad and are actually not too big of a part of the grade. When I looked up his syllabus I thought this would be great as I choke pretty frequently on tests and am really good at doing psets etc., but legit be warned. If you're taking a large amount of units like I did + lab this class will actually drown you.

Let's start with the cons. The thing I probably detested the most about this class is that the homework (book problems) had very little to do with the course overall. You did them after reading the chapter and probably never saw them again. There were so many small things and complicated problems that I had to churn out but then never saw discussed in the class or test so it kind of encouraged not actually learning those skills. Aside from the book problems, every 1.5 weeks you'll have a "literature assignment" that requires you to read a paper and then summarize it. This takes SO long. Please do not underestimate trying to basically read a foreign language for your first assignments bc it's so hard. Legit try to find shorter articles and it will help you even if it's less interesting. This will however definitely help you start reading papers which is a necessary skill but it takes a huge amount of time. This reading papers slowly builds into your poster project and paper which requires even more papers to be read and takes one of your saturdays later in the quarter to go and present in front of your peers. I pulled multiple all-nighters for this as I also had other classes that I had to be focusing on which really sucked. It was a delightful experience overall but so much work. Finally, the pacing is awful because after this poster presentation which had a homework assignment literally due a few days after as well as a midterm. That was quite fun and I bombed the second one but still ended up getting an A. I think you prob shouldn't worry about your grade as much as your health in this class :(

Overall, just know when he says it's 3x the work it really is. You'll learn a lot about chemistry but not with too much of a focus on 20B material and rather it's real-world applications. Stay safe :)

Paul is definitely a GREAT professor for Chem 20BH!
First of all, I believe all of you who are viewing this page must have noticed the difference between Paul's rating for Chem 20B and Chem 20BH. This arises from the different nature of these two: If you just want to learn some chemistry and pass 20B(H) as easily as possible, stay away from Paul's class; if you want to really learn SCIENCE, including chemistry and involving all aspects of science (research skills, analytic skills, etc.), you can hardly find a better professor than Paul.
Second, I acknowledge that the workload is heavy, but it is well manageable. In the quarter I took this Paul's class (winter quarter of my first year ---- as most of you who will take this course will most probably take at this time of the year), I took 5 courses including 2 maths and a cluster and I survived. Other comments have talked about what to expect, and they are all precise. However, if you are very academic, you will definitely handle all this.
Last but not least, Paul is pretty chill. Just think about how many 60-year-old professor would like their students to call them by their first name instead of Prof. X or Dr. X. His class is extremely interesting, where Paul would occasionally tell jokes and personal experience. And again, if you are a very science guy and want to get into a lab, Paul is extremely helpful. He knows who to turn to regarding every aspect of chemistry or materials science if he can't answer himself.
The only minor problem with this course is that the exams are very comprehensive. As other comments have said, many of the materials are complementary, which results in a heavy workload. It will be great if you command them all, but since most of us can't, you should be wise at telling the most important points from others (as I did). Other than that, Paul's course is very amazing.

This class was genuinely enjoyable. I loved learning about the broader concepts and applications of chemistry, and it really helped me grow in how I think as a scientist.

That said, you cannot afford to fall behind. The workload requires constant attention, and attendance Monday through Friday makes time management challenging—especially if you’re taking other classes. It’s demanding, but also very rewarding.

Paul grades fairly (if not somewhat leniently), so I wouldn’t stress too much about your grade as long as you stay engaged and find some interest in the material. Exams (midterms and final) focus on applying concepts rather than throwing unexpected curveballs, and they’re open note—which helps a lot. I printed everything, though I ended up using very little of it during the exams. Overall, a challenging but fulfilling class—enjoy it!

Although almost every review has already stated this, this class is an extreme amount of work and isn't something to be taken lightly. When I originally heard of the amount of work in this class, I thought that I would be fine and wouldn't need to worry about it. However, this class will be a lot of work no matter what despite what the grade distribution might show. There's a lot of homework and classwork to be done in this class and there was more work than my other three classes combined. However, the way this class is structured makes it so as long as you put forth your best effort and a little more, you won't have to worry about your grade which is nice. Midterms and finals aren't worth a large portion of your grade and are forgiving due to the group phase. Also, midterms and finals are online and open internet/note but there's a reason why it is that way. The midterms and finals are extremely difficult and you need to do research to work through them a lot of the time so good luck. In my opinion it does help you as a researcher since it forces you to think critically and uses your resources. It's worth noting that this class overall is more like a research class since the professor really wants everyone to be in a lab after taking the class and he will help you. Because of this, you can see that in the homework assigned and the way the tests are structured. For homework, other than the textbook problems, there are scientific paper review assignments and a final project where you do research which is why this class feels more like a research than a general chemistry class. Although I highly struggled in this class, I managed to end with an A and do not regret taking this class at all.

Chem 20BH is a significant amount of work; on top of doing the weekly textbook assignments, there are also scientific literature assignments every other week and a LARGE research project that creeps a lot faster than you'd expect. That said, I feel like I learned a lot and Paul and the TA/LAs are all very very helpful and all want to help you succeed. Office hours are a huge help (attending at least one is mandatory for participation), and a great way to get into research. If you're aiming to get connected with professors, this class is definitely worth it because Paul will go out of his way to help you out with that. The grading scale is weighted less towards the tests, but there is a lot of extra credit available so as long as you do all the work, your grade should be very favorable.

This is the best class at UCLA. It is hard (honors), but well worth it. Paul takes students and turns them into scientists with labs, connections, and experience. After this class, you have a guaranteed lab, you'll be reading scientific articles, and you'll be attending seminars, meeting all the top scientists and professors at UCLA. Paul is very engaging in class, and often tells stories from his millions of miles of traveling and his interactions with hundreds of Nobel prize laureates

Many reviews have already captured the amount of work required for Chem 20BH. If you look at the distribution of grades, you will be able to see that, given the proper amount of effort, it is quite easy to get an A. Paul WILL reward you for trying hard, showing up to office hours (he makes a point of ensuring everyone goes), and putting effort into this class. By the end, you aren't really concerned about your grade, and it's more the skills in research and intuition that you've gained that matter.

This class is an experience that is very much worth it for people interested in going into research as a career, looking to gain advice on joining research labs, grad school, etc. It is an experience more than anything else. I would not exactly describe this class as enjoyable, but looking back I would definitively take it again; he pushes a "foreign language immersion" philosophy and in turn expects a lot from his students, including putting in tons of extra time outside of class to go to office hours, seminars, etc. beyond the arduous amount of assignments he gives. Ultimately, you could probably get by without too much pain if you just show up and put half-effort into the assignments, but then you're losing the whole point of the class. You SHOULD be kind of a try-hard in this class because then you'll get the most out of it. But, as a result, the class takes so much of your time and the "4-unit" thing is essentially irrelevant because Chem 20BH was the ONLY class I was ever truly focused on over Winter quarter, despite taking 20 units of credit.

I said multiple times over the quarter that Chem 20BH was ruining my life, that I wanted to switch majors, that I hated Chemistry, and I wasn't exactly lying; but perhaps the catharsis at the end when you turn in your final exam and feel the weight of Chem 20BH lift off your shoulders makes you realize that the class is worth it in the end.

Only take Chem 20BH if you are committed to the experience, to letting Winter Quarter be defined by this class. You have to be committed from Day 1 to the workload. But if you take the class, you will learn to love it, make meaningful relationships with Paul and your peers, and recite LAnOx and GRedCat an unhealthy amount of times. And, in the end... it's kind of an easy A.

This is a great class, I definitely recommend taking it instead of CHEM 20B if you can get it. It may be more work i'm not sure but the projects make it more interesting/applicable. I didn't find the class super stressful.

Paul is a pretty awesome professor for this class specifically, which he cares a lot about. He's also really active in helping students to get research positions. He's really enthusiastic about chemistry and he encourages his students to attend different seminars and other events frequently. You get extra credit on exams for describing research labs you've looked into and seminars you've watched. There's a lot of work (final research paper, like 3 different homework assignments due each week, doing a video presentation, etc) but overall I would totally recommend the class if you're willing to put in the work (and if the regular 20B professors that quarter are bad). Paul's tests are fair and he accepts different answers if your argument makes sense (ie: what type of spectroscopy would you use to find x thing about this molecule).