Free-response practice
Chemistry free-response questions
Free-response questions (FRQs) are the part of the AP® Chemistry exam where you write your own answers. Here they're grouped the way the exam uses them. Write your answer, then score it yourself with the rubric and a model answer, or sign in for free AI scoring.
16 questions · 2 types
Long free-response question
A multipart question, often built around a lab setup or a data table, that mixes several topics. You calculate, explain and justify your answers across many lettered parts.
On the exam: 3 questions (Questions 1–3), part of the 1-hour-45-minute free-response section; calculator allowed. Plan on about 23 minutes for one.
Units 1, 2 and 3
Identifying an unknown liquid
10 points · about 23 minutes · calculator allowed
Units 4 and 8
Titrating an unknown weak acid
10 points · about 23 minutes · calculator allowed
Unit 5
Rate law and mechanism for NO and H₂
10 points · about 23 minutes · calculator allowed
Units 6 and 9
Dissolving ammonium nitrate
10 points · about 23 minutes · calculator allowed
Units 2 and 7
The PCl₅ decomposition equilibrium
10 points · about 23 minutes · calculator allowed
Units 4 and 9
A nickel–silver galvanic cell
10 points · about 23 minutes · calculator allowed
Units 3 and 7
Measuring the Ksp of silver chromate
10 points · about 23 minutes · calculator allowed
Short free-response question
A shorter multipart question that sticks to one or two topics. Each part usually asks for one calculation, claim or explanation.
On the exam: 4 questions (Questions 4–7), part of the 1-hour-45-minute free-response section; calculator allowed. Plan on about 9 minutes for one.
Unit 1
Reading a photoelectron spectrum
4 points · about 9 minutes · calculator allowed
Unit 1
Gallium: mass spectrum and composition
4 points · about 9 minutes · calculator allowed
Unit 2
Resonance in the cyanate ion
4 points · about 9 minutes · calculator allowed
Unit 3
A mixture of helium and argon
4 points · about 9 minutes · calculator allowed
Unit 4
Precipitating lead(II) iodide
4 points · about 9 minutes · calculator allowed
Unit 5
Decomposition of hydrogen peroxide
4 points · about 9 minutes · calculator allowed
Unit 6
Adding hydrogen to ethene
4 points · about 9 minutes · calculator allowed
Unit 8
Designing a pH 7.40 buffer
4 points · about 9 minutes · calculator allowed
Unit 9
Hydrogen and oxygen: favorable but slow
4 points · about 9 minutes · calculator allowed