At a glance
- 2027 exam
- Thursday, May 6, 2027, afternoon session
- Length
- 3 hours 15 minutes
- Format
- 60 multiple choice + 7 free response
- Delivery
- Hybrid: Bluebook + handwritten free response
- Fee outside US/Canada
- $129 per exam (2026-27)
AP Chemistry exam format
| Section | Questions | Time | Weight |
|---|---|---|---|
| Section I: multiple choice | 60 (single questions and sets on shared data) | 1 hour 30 minutes | 50% |
| Section II: long free response | 3 (10 points each) | 1 hour 45 minutes for all seven | 50% for all seven |
| Section II: short free response | 4 (4 points each) |
Source: AP Central exam page, checked 6 October 2026. An approved calculator is permitted, and a periodic table and equations sheet are provided in Bluebook and on paper.
The nine units and their multiple-choice weighting
| Unit | Multiple-choice weighting |
|---|---|
| 1. Atomic Structure and Properties | 7 to 9% |
| 2. Compound Structure and Properties | 7 to 9% |
| 3. Properties of Substances and Mixtures | 18 to 22% |
| 4. Chemical Reactions | 7 to 9% |
| 5. Kinetics | 7 to 9% |
| 6. Thermochemistry | 7 to 9% |
| 7. Equilibrium | 7 to 9% |
| 8. Acids and Bases | 11 to 15% |
| 9. Thermodynamics and Electrochemistry | 7 to 9% |
Unit 3 (intermolecular forces, gases, solutions and spectroscopy) carries the most weight. The free-response section samples all units.
Where students lose points
Calculation errors are the obvious loss: dimensional analysis set up the wrong way, moles of the wrong species, a missing coefficient from the balanced equation, or an ICE table with the wrong change values. These are fixable with a consistent written method.
The less obvious loss is in explanations. AP Chemistry free-response questions often ask students to justify a claim at the particle level: why one substance has a higher boiling point, why the first ionization energy of one element is larger, why a buffer resists a pH change. Readers want the specific interaction named (for example London dispersion forces versus hydrogen bonding) and connected to the observation. 'It has stronger bonds' usually scores nothing, partly because it confuses intermolecular forces with covalent bonds.
Equilibrium and acids and bases are where many strong students lose confidence: deciding when to use Ka, Kb or the Henderson-Hasselbalch equation, and reading titration curves. Students also need to be fast without a calculator in some multiple-choice items, since many answers come from estimation and reasoning rather than full calculation.
How one-to-one AP Chemistry lessons help
A tutor who teaches AP Chemistry sets up one written method for each type of calculation (stoichiometry, gas laws, equilibrium, titrations, electrochemistry) and has your child use it every time until it is automatic. Explanations are practiced as short written answers, marked against released scoring guidelines, and rewritten until they name the right particle-level idea.
Lessons follow the school's order of units through the year, and from March switch to timed free-response practice, where the seven questions in 105 minutes demand good pacing as well as knowledge.
When to start
AP Chemistry builds tightly: kinetics, equilibrium, acids and bases and electrochemistry all assume stoichiometry and bonding are secure. If the first two units in the fall feel shaky, that is the time to start, because the later units will not get easier on their own. Students who took high school chemistry a year or more ago often benefit from a few review lessons in the summer or early September.
Common questions
When is the AP Chemistry exam in 2027?
Thursday, May 6, 2027, in the afternoon session. Confirm the local start time with your school's AP coordinator.
Is a calculator allowed on the AP Chemistry exam?
Yes, an approved calculator is permitted. A periodic table and a sheet of equations and constants are provided.
Does my child need honors chemistry before AP Chemistry?
College Board recommends a first high school chemistry course and Algebra 2 beforehand. The math is mostly algebra, logarithms for pH, and unit conversion.
Why is AP Chemistry considered so hard?
It combines heavy calculation with precise particle-level explanation, and later units depend on earlier ones. Gaps from the fall tend to show up in the spring.
How much do AP Chemistry lessons cost with LiveTutor?
$15 a lesson, the same rate for every subject, on a weekly plan of 1 to 5 lessons a week billed monthly. The first lesson is a free trial.
Sources
Dates and figures on this page come from these official and published sources. Always confirm deadlines on the official page before acting on them.