AP Chemistry · Exam guide
AP Chemistry Multiple-Choice Guide: 60 Questions in 90 Minutes
The multiple-choice section is half of the AP Chemistry score, with 60 questions in 90 minutes. Many are conceptual, and many give a graph, a table of data, or a particulate diagram. This guide gives a plan for the time and for choosing between options that look alike.
The format
- 60 multiple-choice questions in 90 minutes, then 7 free-response questions in 105 minutes. Each section is half of the exam score.
- A scientific or graphing calculator is allowed, and a periodic table and an equation sheet are provided.
- There is no penalty for a wrong answer, so answer every question.
Question types
| Type | What to do |
|---|---|
| Particle diagrams | Count the particles of each kind, and use conservation of atoms to decide which diagram is correct. |
| Data and graphs | Say what the trend is, then connect it to the chemistry: rate, equilibrium, or energy. |
| Concept explanation | Choose the option that names the reason, such as stronger attractions between particles, not only the result. |
| Calculation | Estimate first with round numbers, then choose the closest option. |
| Lab and error | Think about which step would change the measurement and in which direction. |
A worked example
Which has the higher boiling point, \(\mathrm{CH_3OCH_3}\) (dimethyl ether) or \(\mathrm{CH_3CH_2OH}\) (ethanol), and why?
| Option | Verdict and reason |
|---|---|
| A. Ethanol, because it forms hydrogen bonds between molecules | Correct. Ethanol has an O-H bond, so its molecules hydrogen bond. Dimethyl ether has none. |
| B. Dimethyl ether, because it has a larger molar mass | Wrong. The two have the same molar mass, since they are isomers. |
| C. Ethanol, because it has stronger covalent bonds | Wrong. Boiling does not break covalent bonds, only the attractions between molecules. |
| D. They are equal, because they have the same formula | Wrong. Different structures give different attractions. |
Pacing
- Aim for about 90 seconds per question. Mark and skip anything that needs more than two minutes.
- Do calculation questions last in each set if they look long. Many can be estimated.
- Leave about 5 minutes at the end to fill in every blank.
Common mistakes
- Choosing the answer with the most chemistry vocabulary instead of the one that explains the observation.
- Confusing breaking bonds with overcoming intermolecular attractions.
- Using the wrong sign for a quantity such as the enthalpy change.
- Skipping units in a calculation and ending up off by a power of ten.
Frequently asked questions
Is there a penalty for guessing?
No. Answer every question.
Can I use a calculator on the multiple-choice section?
Yes. A scientific or graphing calculator is allowed on the whole exam.
Are there reference sheets?
Yes. A periodic table and an equation sheet are provided.
How should I practice for particle diagram questions?
Draw them yourself for reactions and mixtures, and check that atoms are conserved.
Where can I find the official format?
Exam formats change a little from year to year, so check the current course and exam description on the College Board site before test day.
Keep practicing
Every lesson in the AP Chemistry course ends with practice problems and an Exam focus box that shows how the topic is tested, and every unit has a review with worked answers. These free lessons also build the skills the free-response section tests:
See the AP Chemistry course Free lessons and lesson list
More AP Chemistry guides (8)
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- AP Chemistry Equilibrium Question Explained: ICE Tables, Q Versus K and Le Chatelier
- AP Chemistry Acid-Base and Buffer Question Explained: pH, Ka and the Henderson-Hasselbalch Equation
- AP Chemistry Particle-Level Explanations: How to Explain Trends, Boiling Points and Bonding
- AP Chemistry Lab and Data Questions Explained: Graphs, Beer's Law and Sources of Error
- AP Chemistry Stoichiometry: Limiting Reactant and Percent Yield, Step by Step
- AP Chemistry Kinetics Question: Rate Laws from Initial Rates
- AP Chemistry Thermochemistry and Thermodynamics: Calorimetry and Gibbs Free Energy
AP is a registered trademark of the College Board, which is not affiliated with and does not endorse this site. This guide is our own explanation of the question types and scoring. For the official scoring guidelines, see the College Board.