AP Chemistry · Exam Format
AP Chemistry Exam Format & Section Breakdown
A complete walk-through of the AP Chemistry exam, drawn from the College Board AP Course and Exam Description: total timing, per-section breakdown, official unit weightings, and the FRQ types you will see on test day.
Section breakdown and timing
| Section | Items | Time | Weight |
|---|---|---|---|
| Section I — Multiple Choice | 60 questions | 90 minutes | 50% of score |
| Section II — Free Response | 7 questions (3 long, 4 short) | 105 minutes | 50% of score |
Total exam length: 3 hours 15 minutes.
The AP Chemistry exam runs 3 hours 15 minutes end to end and is split into the following sections:
- Section I — Multiple Choice — 60 questions, 90 minutes, 50% of score.
- Section II — Free Response — 7 questions (3 long, 4 short), 105 minutes, 50% of score.
The College Board publishes the full Course and Exam Description (CED) for AP Chemistry on AP Central, including the official unit weightings reproduced below, sample multiple-choice items, and at least one full set of released free-response questions with scoring guidelines. ExamEdge US treats that CED as the source of truth for what is testable; every unit guide on this site corresponds to a unit in the official framework, and every FRQ walkthrough on this site mirrors the structure of a real released question.
Understanding the section breakdown is itself a score-lift technique. Many students who report "I knew the content but ran out of time" did not budget per-question time before walking in. Use the per-question time implied by the table above as a hard pacing limit during practice — for example, if Section II of AP Chemistry gives you 90 minutes for 6 free-response questions, your average is 15 minutes per FRQ, and any FRQ that you have not at least sketched in 15 minutes should be skipped to the next so that you maximize point capture across all six.
The unit weightings below indicate the percentage of multiple-choice questions drawn from each unit in a typical release. Two practical implications: first, no unit is small enough to skip — even a 5–7% unit will contribute a measurable number of multiple-choice points. Second, the highest-weight unit on the exam deserves at least one full study session per week from week 2 onward, because a 17–20% unit will materially move your final score in either direction.
For each section above, the College Board publishes targeted skills (in AP Biology these are called Science Practices; in AP US History they are Historical Reasoning Skills; in AP Chemistry they are Science Practices). The skills do not change between exam years, so a student who masters the skill list will be able to answer next year's questions even though the specific stimuli will differ.
Official unit weightings
The percentages below come from the College Board AP Course and Exam Description for AP Chemistry. They indicate the share of multiple-choice questions drawn from each unit on a typical exam release.
| Unit | Exam weight |
|---|---|
| Unit 1: Atomic Structure and Properties | 7–9% |
| Unit 2: Compound Structure and Properties | 7–9% |
| Unit 3: Properties of Substances and Mixtures | 10–12% |
| Unit 4: Chemical Reactions | 7–9% |
| Unit 5: Kinetics | 7–9% |
| Unit 6: Thermodynamics | 7–9% |
| Unit 7: Equilibrium | 10–12% |
| Unit 8: Acids and Bases | 11–15% |
| Unit 9: Applications of Thermodynamics | 7–9% |
Free-response question types
Every AP Chemistry FRQ falls into one of the published types below. ExamEdge US has a full annotated walkthrough for each one — open any link to see a representative prompt, the College Board-style scoring rubric, a sample student response, and grader commentary on where the points are typically won and lost.
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FRQ 1: Long FRQ — Experimental Design and Analysis
Long FRQ — Experimental Design and Analysis — Annotated walkthrough of an AP Chemistry Long FRQ — Experimental Design and Analysis free-response question, with prompt, scoring rubric, sample student response, and grader commentary.
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FRQ 2: Long FRQ — Quantitative / Algorithmic Problem Solving
Long FRQ — Quantitative / Algorithmic Problem Solving — Annotated walkthrough of an AP Chemistry Long FRQ — Quantitative / Algorithmic Problem Solving free-response question, with prompt, scoring rubric, sample student response, and grader commentary.
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FRQ 3: Long FRQ — Representations and Models
Long FRQ — Representations and Models — Annotated walkthrough of an AP Chemistry Long FRQ — Representations and Models free-response question, with prompt, scoring rubric, sample student response, and grader commentary.
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FRQ 4: Short FRQ — Conceptual Application
Short FRQ — Conceptual Application — Annotated walkthrough of an AP Chemistry Short FRQ — Conceptual Application free-response question, with prompt, scoring rubric, sample student response, and grader commentary.
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FRQ 5: Short FRQ — Calculation Justification
Short FRQ — Calculation Justification — Annotated walkthrough of an AP Chemistry Short FRQ — Calculation Justification free-response question, with prompt, scoring rubric, sample student response, and grader commentary.
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FRQ 6: Short FRQ — Particulate-Level Reasoning
Short FRQ — Particulate-Level Reasoning — Annotated walkthrough of an AP Chemistry Short FRQ — Particulate-Level Reasoning free-response question, with prompt, scoring rubric, sample student response, and grader commentary.