How to Answer AP® Chemistry Free-Response Questions (FRQs) | Examples and Tips

Pay Attention to What the Question Is Asking

Each task verb in an FRQ aligns with specific scoring guidelines, so it is important to focus on these key terms.

• Start by jotting down task verbs and instructions, then outline your response. As you complete each part, mark off the tasks to ensure you've fully addressed everything before moving on to the next question.
• For calculation-based questions, always show your work and round your answer only at the end. Remember to be mindful of significant figures and include properly abbreviated units when needed.

Next, we'll dive into common task verbs and examples of how they're used in FRQs, so you'll know exactly what to do when you encounter them.

Common Task Verbs and Their Meanings

Each FRQ on the AP Chemistry exam uses task verbs that ask you to do something specific. If you correctly complete each requirement that the task verbs ask, you will receive the maximum points possible for that question. Our AP Chem study guide gives detailed explanations of each task verb, so you're fully prepared to respond in the best way possible.

1. Calculate

You will apply mathematical steps such as basic algebra and formulas from the provided Equations and Formula sheet to arrive at a final calculated answer.

Example: Calculate the value of ΔH° for the reaction.

• For this type of question, show your work because it's usually worth a point in addition to the one you receive for arriving at the correct answer.
• Pay attention to significant figures and remember to round only at the end of the calculation.
• Include units with your answer when applicable.
• Use your approved calculator to perform mathematical calculations and ensure accuracy.
• Draw a box around your final answer so the reader can easily pick it out.

2. Describe

You will provide information about a particular process, topic, or experiment.

Example: Describe how you would prepare a 0.25 M solution of KCl(aq).

• Show that you understand the process, topic, or experiment by providing a concrete example after your description of the topic.
• If you're asked to describe the process of doing something in a lab, include the proper glassware you would use. For example, you would measure the volume of a liquid with a graduated cylinder, not a beaker or Erlenmeyer flask.

3. Determine

You will need to come to a decision or conclusion after evaluating specific information provided in the question. This is a test of your critical thinking skills. You could also be asked to perform a calculation with this task verb.

Example: Determine whether your answer to part (a) above supports the student's claim that the reaction is endothermic. Justify your answer.

• To earn maximum points, provide reasoning or evidence showing how you arrived at your determination.

4. Estimate

You will be required to estimate a specific value or parameter from given information such as a graph or Lewis structure. You may also need to apply content knowledge to the given information to correctly answer the question.

Example: Based on the titration curve, estimate the pK_a of the acid.

• If the value you are estimating has units associated with it, include them in your estimation.

5. Explain

You must provide information about why a particular thing happened or the motivations or reasons for its occurrence. You may also need to discuss how something happened.

Example: A student noticed that the pH of the solution barely changed when 0.1 M NaOH(aq) was added to a solution. Explain this observation.

• Use specific examples or data provided in the question.
• Demonstrate that you can make a specific concept understandable to another person.

6. Identify/Indicate/Circle

You will need to indicate or give information pertaining to a specific subject.

Example: Identify the cathode in the galvanic cell.

• The “identify” task verb could also be in the form of “circle,” where you must circle something from a given list.
• Ensure you are doing exactly what the question is asking. For example, if a question asks you to circle a compound, make sure you circle it instead of boxing it or marking it in another way.
• Answer only what is asked and provide reasoning if necessary.

7. Justify

You will provide evidence to show that a particular claim is true.

Example: Which acid is stronger, HNO₃(aq) or CH₃COOH(aq)? Justify your answer based on the particulate representation above.

• You may also be asked to provide reasoning to explain how your evidence supports, defends, or modifies the claim.
• This type of question generally requires using data provided in the FRQ.

8. Make a Claim

You will make an assertion based on evidence or knowledge.

Example: Make a claim about whether the reaction will be exothermic or endothermic.

• Ensure that your claim is clear and directly tied to the evidence presented in the question.

9. Predict/Make a Prediction

You will need to predict the causes or effects of a change in, or disruption to, one or more components in a relationship, pattern, process, or system.

Example: Predict the shift in equilibrium when additional O_₂ is added to the reaction vessel.

• Provide reasoning with your prediction to explain why the predicted change will occur.

10. Represent/ Draw/ Write an Equation/ Complete a Diagram

You will use appropriate graphs, symbols, words, and/or models to describe phenomena, characteristics, and/or relationships.

Example: Represent the neutralization reaction between NaOH and HCl by writing the balanced chemical equation.

• Make sure to include appropriate labels, states of matter, and ensure that the equation is balanced. For diagrams, be clear and add labels as needed.