AP Chemistry past papers and free-response questions
College Board publishes the AP Chemistry free-response questions every year, with scoring guidelines, sample student responses and a chief reader report. This page collects every year it currently makes public, 2023 to 2026, to preview, open or download. The exam has 7 free-response questions in 1 hour 45 minutes: 3 long questions worth 10 points and 4 short questions worth 4 points.
On this page
AP Chemistry free-response questions by year
Each file opens from College Board's official site. Preview shows it here, Open in new tab gives you the full screen, and Download saves a copy to print.
2026
- Free-response questionsPreviewOpen in new tabDownload
- Scoring guidelinesPreviewOpen in new tabDownload
- Sample responses and chief reader reportCollege Board usually adds these in the autumn after the exam
2025
- Free-response questionsPreviewOpen in new tabDownload
- Scoring guidelinesPreviewOpen in new tabDownload
- Chief reader reportPreviewOpen in new tabDownload
- Scoring statisticsPreviewOpen in new tabDownload
- Score distributionsPreviewOpen in new tabDownload
- Sample student responsesQ1Q2Q3Q4Q5Q6Q7
2024
- Free-response questionsPreviewOpen in new tabDownload
- Scoring guidelinesPreviewOpen in new tabDownload
- Chief reader reportPreviewOpen in new tabDownload
- Scoring statisticsPreviewOpen in new tabDownload
- Score distributionsPreviewOpen in new tabDownload
- Sample student responsesQ1Q2Q3Q4Q5Q6Q7
2023
- Free-response questionsPreviewOpen in new tabDownload
- Scoring guidelinesPreviewOpen in new tabDownload
- Chief reader reportPreviewOpen in new tabDownload
- Scoring statisticsPreviewOpen in new tabDownload
- Score distributionsPreviewOpen in new tabDownload
- Sample student responsesQ1Q2Q3Q4Q5Q6Q7
Source: AP Chemistry past exam questions on AP Central. All papers are © College Board.
What each AP Chemistry free-response question tests
Use this index to find past questions on the topics you need to practise. The descriptions are our own summaries.
2026
| Q1 | Calorimetry with KCl: electron configuration, ionic radius and enthalpy |
|---|---|
| Q2 | Chromate and dichromate ions: Lewis diagrams and bonding |
| Q3 | Nitrous acid: weak acid equilibrium and pH |
| Q4 | Decomposition of P₄: gas-phase equilibrium and Kp |
| Q5 | CBrClF₂: bond polarity and molecular geometry |
| Q6 | Spectrophotometry with a calibration curve: Beer's law |
| Q7 | Sodium reacting with oxygen: enthalpies of formation |
2025
| Q1 | Mass spectrum of magnesium: isotopes and average atomic mass |
|---|---|
| Q2 | Combustion analysis of ascorbic acid: empirical formula |
| Q3 | White phosphorus: Lewis structure and bonding |
| Q4 | Methanol and formaldehyde mixture: hybridisation and intermolecular forces |
| Q5 | Two compounds: VSEPR geometry and boiling points |
| Q6 | Zinc and aluminium galvanic cell: electrochemistry |
| Q7 | Glycolate ion: acid-base behaviour and Lewis diagrams |
2024
| Q1 | Lactic acid and sodium hydroxide: acid-base titration |
|---|---|
| Q2 | Maleic acid and sodium bicarbonate: stoichiometry |
| Q3 | Tarnish on sterling silver: composition and redox |
| Q4 | Specific heat capacity of a metal: calorimetry |
| Q5 | Hydrogen and iodine forming HI: equilibrium |
| Q6 | Decomposition of NO₂: reaction rates and rate law |
| Q7 | Making a salt solution for chromatography: molarity |
2023
| Q1 | Manganese compounds: electron configuration and oxidation states |
|---|---|
| Q2 | Gaseous AlCl₃: bond enthalpy and thermochemistry |
| Q3 | Calcium carbonate with hydrochloric acid: net ionic equation and gas stoichiometry |
| Q4 | Methylamine buffer: preparation and pH |
| Q5 | HCl gas and solution: ideal gas law and acids |
| Q6 | HBr and HF liquids: intermolecular forces |
| Q7 | Strontium hydroxide: Ksp and solubility |
AP Chemistry exam format
| Section | Questions | Time | Score |
|---|---|---|---|
| Section I: multiple choice | 60 questions | 1 hour 30 minutes | 50% |
| Section II: free response | 7 questions: 3 long (10 points each) and 4 short (4 points each) | 1 hour 45 minutes | 50% |
The exam is hybrid digital: multiple-choice answers go into the Bluebook app, and free-response answers are handwritten in a paper booklet. A calculator is allowed, and reference information including the equations and periodic table is provided. The free-response format has been the same in every year on this page.
How to use past free-response questions
- Start with the newest papers. They match the current exam most closely.
- Do one question at a time, timed. Use the timings in the exam format above, with no notes open.
- Mark yourself strictly with the scoring guidelines, point by point, before reading anything else.
- Compare with the sample responses to see exactly what earned or lost each point.
- Read the chief reader report for the mistakes most students made that year, and keep a list of your own.
- Go back to weak topics using the topic index, then redo the question a week later.
Tips specific to AP Chemistry:
- Show the full calculation with units and significant figures. Each step can earn a point even if the final answer is wrong.
- Explain with particles: when asked why, describe the interactions between particles, not just a rule such as 'like dissolves like'.
- For equilibrium and acids, write the expression (K or Ka) before substituting numbers.
- Time yourself: about 23 minutes for each long question and 9 minutes for each short question leaves time to check.
Free AP Chemistry practice questions
Ten original multiple-choice questions written by our tutors in the style of the exam. Choose an answer to see if you are right and why.
Answered 0 of 10 · 0 correct
1. How many moles are in 18.0 g of water (molar mass 18.0 g/mol)?
Show answer
B. n = m/M = 18.0/18.0 = 1.00 mol.
2. What is the pH of 0.010 M HCl(aq)?
Show answer
B. HCl is a strong acid, so [H⁺] = 0.010 M and pH = −log(0.010) = 2.
3. Which substance has the highest boiling point?
Show answer
D. Water molecules form hydrogen bonds, the strongest intermolecular forces in this list.
4. What is the molecular geometry of NH₃?
Show answer
B. Three bonding pairs and one lone pair around N give a trigonal pyramidal shape.
5. What volume does 1.00 mol of an ideal gas occupy at 273 K and 1.00 atm?
Show answer
B. V = nRT/P = (1.00)(0.08206)(273)/1.00 ≈ 22.4 L.
6. For N₂(g) + 3H₂(g) ⇌ 2NH₃(g), ΔH < 0. What happens to K when the temperature is increased?
Show answer
B. The forward reaction is exothermic, so raising the temperature favours the reverse reaction and K decreases.
7. What is the oxidation number of Mn in KMnO₄?
Show answer
D. K is +1 and each O is −2: +1 + Mn + 4(−2) = 0, so Mn = +7.
8. A first-order reaction has rate constant k = 0.0693 s⁻¹. What is its half-life?
Show answer
C. For first order, t½ = ln 2/k = 0.693/0.0693 = 10.0 s.
9. A buffer contains equal moles of a weak acid HA and its conjugate base A⁻. What is the pH?
Show answer
B. By the Henderson-Hasselbalch equation, pH = pKa + log([A⁻]/[HA]) = pKa + log 1 = pKa.
10. 4 mol of H₂ react with 1 mol of O₂: 2H₂ + O₂ → 2H₂O. How many moles of water form?
Show answer
B. 1 mol O₂ needs only 2 mol H₂, so O₂ is limiting and makes 2 mol of water.
Frequently asked questions
Are AP Chemistry past papers free?
Yes. College Board publishes the AP Chemistry free-response questions, scoring guidelines and sample responses free on AP Central. This page links to those official files so you can preview, open or download them.
Why are there no older AP Chemistry papers before 2023?
College Board currently makes the most recent years public on AP Central and removed older years from public access. Teachers can find many older released questions in AP Classroom.
Can I get full AP Chemistry past exams with the multiple-choice section?
College Board does not publish full past multiple-choice sections publicly; complete practice exams are released to teachers through AP Classroom. The free-response questions, which are half of your score, are public, and this page has 10 original multiple-choice questions to practise with.
How is the AP Chemistry free-response section scored?
The 3 long questions are worth 10 points each and the 4 short questions 4 points each, 46 points in total.