AP Chemistry review: exam format, the 9 units, and how to study
The AP Chemistry exam is a 3-hour-15-minute test of 60 multiple-choice questions and 7 free-response questions, with a reference packet and periodic table provided throughout. This guide covers that format, all nine units, how the exam is scored, and a study plan built to earn a 5.
What’s on the AP Chemistry exam
The AP Chemistry exam splits evenly into two sections. Section I is 60 multiple-choice questions in 90 minutes, worth 50%, and you take it without a calculator — it mixes discrete questions with sets built on lab data, graphs, and particulate-level models. Section II is the free response: 7 questions in 105 minutes, also 50%, made up of 3 long questions worth 10 points each and 4 short questions worth 4 points each, and here a calculator is allowed.
For both sections you are given the official reference packet of equations and constants and a periodic table, so the exam tests whether you can choose and apply the right relationship, not whether you memorized it. The whole thing runs 3 hours and 15 minutes, and it is a hybrid format: the multiple choice is in the Bluebook app while the free response is handwritten on paper.
The 9 units of AP Chemistry
AP Chemistry is organized into nine units. Intermolecular forces is by far the heaviest, and acids and bases is the next most tested — together they shape a large share of the exam.
How AP Chemistry is scored
Your multiple-choice and free-response points combine into one composite score, which the College Board scales to a 1–5 each year. Be realistic about the bar: AP Chemistry is one of the lower-scoring AP exams, with a recent pass rate around 54% and a mean score below 3, so steady practice matters more here than on easier exams.
To turn a practice raw score into a predicted 1–5, use our AP Chemistry score calculator.
How to study for AP Chemistry
Because the equations are provided, the points come from reasoning — knowing which relationship applies, what each variable means, and how to justify it in writing. Build your review around understanding, and learn the reference packet so you can find a formula instantly.
Then practice the free response heavily, since it is half the exam and rewards clear justification. Work past questions against the rubric with our AP Chemistry FRQ guide, drill one unit at a time using the Progress Check walkthroughs, and keep our equation sheet and cheat sheet close for fast review.
When is the AP Chemistry exam, and how long is it
AP Chemistry is given once a year during the College Board’s May testing window, and the exam takes 3 hours and 15 minutes. The exact date and start time are set each year, so confirm the current schedule on the official AP calendar with your coordinator before you plan around it.
Frequently asked questions
Quick answers, written by humans.
How many questions are on the AP Chemistry exam?
There are 60 multiple-choice questions and 7 free-response questions — three long and four short — split into two equally weighted sections.
How long is the AP Chemistry exam?
Three hours and 15 minutes: 90 minutes for the multiple choice and 105 minutes for the seven free-response questions.
Is a calculator allowed on the AP Chemistry exam?
Only on the free-response section. The multiple-choice section is done without a calculator, though the reference packet and periodic table are provided for both.
How many units are on AP Chemistry?
Nine, from atomic structure to electrochemistry. Intermolecular forces (Unit 3) is the heaviest at 18–22%, with acids and bases close behind.
Is AP Chemistry hard?
It is one of the more demanding AP exams — recent pass rates have sat around 54%, with a mean score below 3. Our honest difficulty breakdown goes deeper.
Is the AP Chemistry exam digital?
It is a hybrid: the multiple-choice section runs in the Bluebook app, while the free-response answers are handwritten in a paper booklet.