Verified for the 2027 AP exam

AP Chemistry Study Guide & Review

Connect atomic and molecular models, reactions, kinetics, equilibrium and thermodynamics through multiple representations, quantitative calculations, experimental data and evidence-based scientific argument throughout the current AP Chemistry course.

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  1. 01Learn concepts
  2. 02Practise questions
  3. 03Review mistakes

How to study AP Chemistry

AP Chemistry is cumulative because a later calculation often depends on an earlier particle model. Use the nine-unit syllabus map to locate the exact Topic and its prerequisites. For each problem, connect the observable phenomenon to a particulate or molecular model, represent it with equations, diagrams or data, choose a mathematical relationship with units and explain whether the result supports the chemical claim.

Rebuild a weak model in Concept, retrieve relationships and conditions in Mastery and apply them in the Question Bank. After marking, classify the first failure as prerequisite, model, representation, stoichiometry, units, calculation, experimental method, data interpretation or argumentation. Repair that failure and answer a matched unfamiliar question without notes.

Practise chemistry across representations

Use current AP Chemistry Topics to combine particle models, symbolic work, mathematical routines, experiments, data and evidence-based conclusions in one repeatable process.

Structure and properties

Atomic structure, bonding, molecular geometry, intermolecular forces and measured properties

Move from spectral, structural or property evidence to a particle-level model, then represent that model symbolically. Compare competing explanations and make the selected structure or interaction account for the observed trend.

Practise structure

Substances, mixtures and reactions

Solutions, spectroscopy, stoichiometry, titration, net ionic equations and reaction evidence

Represent the particles and balanced process before calculating. Identify the limiting relationship, retain units and significant reasoning steps, then connect concentration, composition or yield back to the experimental observation.

Practise reactions

Kinetics and equilibrium

Rate laws, mechanisms, activation energy, reaction quotient and equilibrium constants

Separate rate from extent, use data to select the model and distinguish Q from K. Explain changes through collisions, mechanisms or equilibrium reasoning instead of relying on a memorized directional slogan.

Practise kinetics and equilibrium

Energy, acids and electrochemistry

Thermochemistry, acid-base systems, thermodynamics, cells and electrolysis

Define the system, preserve sign conventions and connect energy, equilibrium or potential to process direction. Check approximations and units, then explain the numerical result using particles, species and driving forces.

Practise energy and acids

Laboratory and FRQ reasoning

Variables, methods, graphs, uncertainty, error, calculations and evidence-based argument

Identify the question, variables and controls before processing data. Represent evidence clearly, distinguish random uncertainty from systematic error and write a conclusion no broader than the method and results can support.

Practise lab reasoning

Where to start

Start from one known chemistry Topic or use a diagnostic to reveal the earliest repeated model, quantitative, method or evidence failure.

Choose your starting point

  1. I know the weak Topic

    Open its exact Unit, identify the prerequisite model and list the representation, relationship and evidence the Topic requires.

    Browse all nine Units

  2. I do not know what is weak

    Use a mixed diagnostic and stop at the first repeated model, setup, unit, method or explanation error.

    Start a diagnostic

Choose the right starting point

  1. Model and represent

    Connect the observation to particles, structure or energy, then express it with an equation, diagram, graph or table.

    Review a Concept

  2. Retrieve and calculate

    Choose the relationship from chemical conditions, complete the setup with units and test whether the result is reasonable.

    Check Mastery

  3. Explain, evaluate and repair

    Use data and principles to justify the conclusion, evaluate the method and correct the first invalid reasoning step.

    Practise questions

Explore all nine AP Chemistry units

Navigate 91 Topics across the nine official effective-Fall-2024 Units. Use current College Board MCQ ranges to plan revision while tracing prerequisite models and quantitative relationships across the complete course.

9
syllabus groups
91
mapped topics

1 Atomic Structure and Properties

Open unit questions
1.1 Moles and Molar Mass1.2 Mass Spectra of Elements1.3 Elemental Composition of Pure Substances1.4 Composition of Mixtures1.5 Atomic Structure and Electron Configuration1.6 Photoelectron Spectroscopy1.7 Periodic Trends1.8 Valence Electrons and Ionic Compounds

2 Compound Structure and Properties

Open unit questions
2.1 Types of Chemical Bonds2.2 Intramolecular Force and Potential Energy2.3 Structure of Ionic Solids2.4 Structure of Metals and Alloys2.5 Lewis Diagrams2.6 Resonance and Formal Charge2.7 VSEPR and Hybridization

3 Properties of Substances and Mixtures

Open unit questions
3.1 Intermolecular and Interparticle Forces3.2 Properties of Solids3.3 Solids, Liquids, and Gases3.4 Ideal Gas Law3.5 Kinetic Molecular Theory3.6 Deviation from Ideal Gas Law3.7 Solutions and Mixtures3.8 Representations of Solutions3.9 Separation of Solutions and Mixtures3.10 Solubility3.11 Spectroscopy and the Electromagnetic Spectrum3.12 Properties of Photons3.13 Beer-Lambert Law

4 Chemical Reactions

Open unit questions
4.1 Introduction for Reactions4.2 Net Ionic Equations4.3 Representations of Reactions4.4 Physical and Chemical Changes4.5 Stoichiometry4.6 Introduction to Titration4.7 Types of Chemical Reactions4.8 Introduction to Acid-Base Reactions4.9 Oxidation-Reduction (Redox) Reactions

5 Kinetics

Open unit questions
5.1 Reaction Rates5.2 Introduction to Rate Law5.3 Concentration Changes Over Time5.4 Elementary Reactions5.5 Collision Model5.6 Reaction Energy Profile5.7 Introduction to Reaction Mechanisms5.8 Reaction Mechanism and Rate Law5.9 Pre-Equilibrium Approximation5.10 Multistep Reaction Energy Profile5.11 Catalysis

6 Thermochemistry

Open unit questions
6.1 Endothermic and Exothermic Processes6.2 Energy Diagrams6.3 Heat Transfer and Thermal Equilibrium6.4 Heat Capacity and Calorimetry6.5 Energy of Phase Changes6.6 Introduction to Enthalpy of Reaction6.7 Bond Enthalpies6.8 Enthalpy of Formation6.9 Hess’s Law

7 Equilibrium

Open unit questions
7.1 Introduction to Equilibrium7.2 Direction of Reversible Reactions7.3 Reaction Quotient and Equilibrium Constant7.4 Calculating the Equilibrium Constant7.5 Magnitude of the Equilibrium Constant7.6 Properties of the Equilibrium Constant7.7 Calculating Equilibrium Concentrations7.8 Representations of Equilibrium7.9 Introduction to Le Châtelier’s Principle7.10 Reaction Quotient and Le Châtelier’s Principle7.11 Introduction to Solubility Equilibria7.12 Common-Ion Effect

8 Acids and Bases

Open unit questions
8.1 Introduction to Acids and Bases8.2 pH and pOH of Strong Acids and Bases8.3 Weak Acid and Base Equilibria8.4 Acid-Base Reactions and Buffers8.5 Acid-Base Titrations8.6 Molecular Structure of Acids and Bases8.7 pH and pKa8.8 Properties of Buffers8.9 Henderson-Hasselbalch Equation8.10 Buffer Capacity8.11 pH and Solubility

9 Thermodynamics and Electrochemistry

Open unit questions
9.1 Introduction to Entropy9.2 Absolute Entropy and Entropy Change9.3 Gibbs Free Energy and Thermodynamic Favorability9.4 Thermodynamic and Kinetic Control9.5 Free Energy and Equilibrium9.6 Free Energy of Dissolution9.7 Coupled Reactions9.8 Galvanic (Voltaic) and Electrolytic Cells9.9 Cell Potential and Free Energy9.10 Cell Potential Under Nonstandard Conditions9.11 Electrolysis and Faraday’s Law

AP Chemistry exam format for 2027

The verified 2027 hybrid exam has 60 Bluebook multiple-choice questions in 90 minutes and seven free-response prompts in 105 minutes, viewed digitally and answered by hand.

Paper / componentQuestionsTime% of grade
Section I: Multiple Choice60 questionsDiscrete and stimulus-based sets are completed in Bluebook; permitted calculators and official reference information are available.How to prepare: Practise timed mixed retrieval, model and data interpretation, dimensional discipline and strategic rather than automatic calculator use.1 hour 30 minutes50%
Section II: Free Response7 questions: 3 long and 4 short46 pointsPrompts are viewed in Bluebook and handwritten responses assess all six Science Practices; calculators and official reference information are available.How to prepare: Practise complete setups, units, particle representations, experimental and data reasoning and concise evidence-based explanations by hand.1 hour 45 minutes50%

SourceCollege Board · AP Chemistry ExamAP Chemistry · May 2027 exam

AP Chemistry questions

College Board provides AP Chemistry reference information in print and in Bluebook. Until the exact 2027 booklet is posted, its official page directs students to the periodic table and Equations and Constants reference in the current CED, labeled effective 2025.

An authorized course devotes at least 25% of instructional time to hands-on inquiry, includes at least 16 labs with at least 6 guided-inquiry investigations, and requires students to record and present evidence in written, visual or oral forms.

Later equilibrium, acid-base, thermodynamic and electrochemical work depends on earlier particle models, bonding, reactions, stoichiometry and energy reasoning. When a later answer fails, identify and repair the earliest prerequisite rather than repeatedly practising only the final Unit label.

Yes. College Board permits scientific or graphing calculators on both sections, and Bluebook provides built-in Desmos scientific and graphing options. A four-function calculator is allowed but not recommended; check the live policy for approved handheld models before exam day.