UW–Madison CHEM 343: Organic Chemistry I
CHEM 343 is UW–Madison's first organic chemistry course — structure and bonding, stereochemistry, substitution and elimination reactions, and the beginnings of synthesis — the legendary premed gateway, taken by huge cohorts headed for health professions and chemistry-adjacent majors.
Fennie is independent and not affiliated with University of Wisconsin–Madison. This is an unofficial study guide.
Build my CHEM 343 study planWhat makes it hard
Orgo's reputation comes from a study-strategy trap: it looks like a memorization course but grades like a reasoning course. Exams present unfamiliar molecules and ask you to predict behavior from mechanisms, so flashcarding reactions without understanding electron flow collapses at exactly the moment students feel most prepared. Stereochemistry's 3D reasoning is the other early filter.
What you'll cover
- • Structure, bonding, and resonance
- • Acids and bases in organic chemistry
- • Stereochemistry
- • Substitution reactions (SN1/SN2)
- • Elimination reactions (E1/E2)
- • Intro to synthesis and mechanisms
The CHEM 343 study guide
How to study for UW–Madison CHEM 343, step by step.
- 1
Learn mechanisms, not reaction flashcards
CHEM 343 exams present molecules you haven't seen and ask what happens. Electron-pushing arrows — why the reaction goes — are the transferable skill; memorized product lists are not.
- 2
Build 3D intuition with models early
Stereochemistry filters students in the first half. Use a model kit (or build the visualization habit deliberately) until chirality, conformations, and Newman projections are things you see, not rules you recite.
- 3
Master the SN1/SN2/E1/E2 decision as one framework
Substrate, nucleophile, base, solvent — the four-way competition is the course's centerpiece and a guaranteed exam fixture. Practice deciding the pathway and justifying it on varied examples.
- 4
Draw every practice problem by hand
Orgo is a drawn language: structures, arrows, intermediates. Reading solutions builds recognition; producing the drawings builds the skill exams grade.
- 5
Keep acid-base reasoning sharp
pKa logic decides nucleophile and base behavior all semester. A weekly refresher on acid-base trends quietly improves every mechanism you write.
- 6
Train the reasoning with Fennie
Upload your CHEM 343 materials and Fennie's Daily Plan spaces mechanism practice across the semester with review synced to exams, plus quizzes from your actual course content that test prediction, not just recall. Free to start.
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How Fennie helps with CHEM 343
Fennie's Daily Plans space CHEM 343's mechanism practice the way the course demands — spaced reps across weeks, exam-synced review, stereochemistry given early runway. Chat through why a reaction goes SN2 instead of E2 until the electron-flow reasoning is yours, because predicting unfamiliar reactions is exactly what the exams test.
FAQ
Is CHEM 343 at UW–Madison hard?
It's the classic premed filter, but the difficulty is strategic, not innate: students who memorize reactions collapse on exams that test mechanistic reasoning on unfamiliar molecules. Students who learn electron pushing and practice prediction consistently do well.
How should I study for organic chemistry?
Draw mechanisms by hand daily, learn why each reaction proceeds (electron flow, stability, sterics), and practice predicting outcomes on molecules you haven't seen. Build 3D stereochemistry intuition early with models — it's the first filter and it doesn't yield to flashcards.
What's the hardest part of CHEM 343?
The SN1/SN2/E1/E2 competition by most accounts — deciding which pathway wins given substrate, nucleophile, base, and solvent — with stereochemistry close behind. Both reward framework-level understanding practiced across many varied examples.
Pass CHEM 343 with a plan, not a cram
Upload your CHEM 343 materials and Fennie generates a Daily Plan paced to your deadline — plus chat, flashcards, and quizzes built from the actual course content.
Get started freeMore UW–Madison courses
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CHEM 104 — General Chemistry II
CHEM 104 completes UW–Madison's general chemistry sequence: kinetics, equilibrium, acids and bases, thermodynamics, and electrochemistry, with lab continuing throughout. It's the direct gateway to organic chemistry for premed and science students.