Short answer: work backwards from past papers. CHEM191 exams are far more consistent year to year than students expect, and only a couple of concepts from each lecture actually turn up. Studying every slide equally is the most common way people waste the semester.
The thing nobody tells you in week one
People find CHEM191 intimidating because of the sheer volume of lecture content. Thirty-six lectures, dense slides, a textbook on top. It looks like an enormous amount to know.
But the exams have historically assessed the same core ideas, worded differently each year. Realistically only a handful of concepts per lecture are examinable in a multiple-choice format. Once you have worked through a few past papers you start to see the same skeleton reappear: an equilibrium calculation, a buffer or pH problem, a mechanism, a thermodynamics or redox question.
That does not mean skip lectures. It means the lectures are the input and the past papers tell you what the output looks like.
What to actually do
- Get past papers early, not in the last fortnight. Use them as a map of what matters, not just as a final rehearsal.
- Work the paper before you read the answers. Attempting it cold is where the learning happens. Reading a worked solution feels productive and teaches you much less.
- Mark which concepts repeat. If the same idea appears across three years of papers, that is your priority list.
- Understand, do not memorise. Because the wording changes each year, memorising a past answer does not transfer. Understanding why a reaction goes does.
Both exams are multiple-choice
The mid-semester test and the final are both multi-choice, which changes the skill you need. You are not writing out a derivation, you are recognising which of five plausible options is right, quickly, under time.
That is a trained skill and it is separate from knowing chemistry. The only way to build it is volume: enough questions that reading a stem and identifying what is being asked becomes automatic.
Where students lose easy marks
- Forgetting the lab assessment tests. They are worth a small percentage each, they are open book, and they are the cheapest marks in the paper. Missing one for no reason is a genuinely painful way to lose 2 percent.
- Only practising one problem type at a time. Doing a page of equilibrium problems teaches you to solve equilibrium problems when you already know that is what they are. The exam does not tell you. Mix the types.
- Leaving organic mechanisms until last. They reward practice more than almost anything else in the paper, and they are hard to cram.
The honest summary
CHEM191 is not conceptually brutal. It is a volume-and-format problem, and the students who do well are the ones who figured out early which concepts recur and then drilled them until the exam felt like another practice run.
The catch is that the course itself gives you very little practice material. That is exactly the gap we built CHEM191 practice questions to fill, worked lecture by lecture and free to start.
