AP Chemistry

The entire universe is built from a tiny Lego set, and we're going to show you how all the pieces snap together.

18 days — make them count.

Tuesday, May 5, 2026

Start Unit 1 — it's free →Explore the course ↓

46%Multiple Choice60q · 90 min · calculator

54%Free Response7q · 105 min · calculator

of students scored 4 or higher in 2025

168,833 test-takers

2,197 colleges grant credit

5 · 18%

4 · 29%

3 · 31%

2 · 16%

1 · 6%

3.4 avg

543 (passing)21

All of AP Chemistry is an argument about structure and energy.

Electron configuration determines how atoms bond, how molecules are shaped, and how substances behave. That's the structural half. Whether a reaction actually happens, and how fast, depends on thermodynamics and kinetics. That's the energy half. The course builds both arguments simultaneously, because neither is complete without the other.

Intermolecular forces and acids/bases dominate the exam — students who treat them as memorization units instead of structure-energy arguments lose the most points.

The AP exam places significant emphasis on Intermolecular Forces and Properties, as well as Acids and Bases, which together account for a substantial portion of the test's content.

How the course builds

Structure and Properties · Scale, Proportion, and Quantity · Transformations

Atomic Structure and PropertiesEstablishes the foundational understanding of electron configuration and atomic theory, which are crucial for understanding molecular interactions.

7–9% of exam

Molecular and Ionic Compound Structure and PropertiesExplores how atomic structure influences bonding and molecular geometry, linking atomic properties to molecular behavior.

7–9% of exam

Intermolecular Forces and PropertiesConnects molecular structure to macroscopic properties, emphasizing the role of intermolecular forces in physical properties and phase changes.

18–22% of exam

Chemical ReactionsIntroduces the concept of chemical change, linking molecular interactions to reaction types and stoichiometry.

7–9% of exam

KineticsExplores the rates of chemical reactions, providing insight into the dynamic nature of reactions and the factors affecting them.

7–9% of exam

ThermodynamicsExamines energy changes in reactions, focusing on enthalpy, entropy, and free energy, which are essential for understanding reaction feasibility.

7–9% of exam

★ Hardest unitEquilibriumExplains the balance of chemical reactions, integrating kinetics and thermodynamics to understand dynamic equilibrium.“Students often struggle with the abstract nature of dynamic equilibrium and the mathematical complexity of equilibrium constants.”

7–9% of exam

Acids and BasesFocuses on proton transfer reactions, applying equilibrium concepts to acid-base chemistry and pH calculations.

11–15% of exam

Applications of ThermodynamicsApplies thermodynamic principles to real-world scenarios, reinforcing the connection between energy changes and chemical processes.

7–9% of exam

Unit 7: Equilibrium is where most students hit a wall.

Students often struggle with the abstract nature of dynamic equilibrium and the mathematical complexity of equilibrium constants.

A solid understanding of both kinetics and thermodynamics is required, which can be challenging if earlier units were not fully mastered.

What You Need

Algebra IDimensional analysisScientific notation and significant figuresGraph and table interpretationBasic experimental design and error analysisGeometryIntroductory high school chemistry or equivalent lab scienceClaim-evidence-reasoning in science

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