AP Chemistry- How to Prepare for the Most Challenging AP Subject By Azusa

Chemistry ranks among the most challenging AP topics as both a course and an exam. Let’s consider this following statistic: in 2020, just 10% of students taking the test earned a 5, while 18% earned a 4.

So what do you need to do in order to be a top scorer?

Keep reading below!

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The entire test is 3 hours and 15 minutes. It’s divided into the 2 sections, each with equal weight:

  • Multiple Choice (no calculator allowed): 1.5 hours, 60 4-choice questions
  • Free Response Questions (calculator allowed): 1.75 hours, 4 short-response and 3 long-response questions.


What’s tested? 

General “application” topics comprise Data Analysis and Representation, Experimental Design, and Problem Solving, but these are placed in the context of more subject-specific, or technical topics. These include (in presence from highest to lowest):

  • Intermolecular Forces and Properties 
  • Acids and Bases 
  • Atomic Structure and Properties, Molecular and Ionic Compounds, Chemical Reactions, Thermodynamics, Equilibrium, Kinetics


How should you prepare?

Be thorough!

The most important thing is to be prepared from the get-go. This means taking solid notes in class lectures and going through any textbook materials or problems sets in earnest. Since there is a lot of information to handle, you want to secure your foundations over the long-term. Also remember that much of chemistry is cumulative in the sense that one topic builds upon another. Achieve a firm grasp on concepts like Atomic Structure, Chemical Reactions (Stoichiometry!), and Molecular and Ionic compounds. And…familiarize yourself with formulas. Although you’ll get a sheet of formulas on the exam, it won’t be of a whole lot of use to you unless you know how to apply them correctly. 

Be proactive!

Just because you wrote up a great set of notes does not mean that you are all set for the exam. You will need to set aside extra time to review them and practice with additional materials (see “Resources” below), and take mock exams.

Depending on which administration period your school decides upon (see 2021 Test Dates below), you’ll want to give yourself 8-12 weeks to adequately cover each topic in depth. Make a study outline so you don’t feel like there’s a massive time crunch on your hands. Factor in times such as weekends to take weekly mock exams. 

Be detailed!

When you’re doing problem sets, get in the habit of showing your work. This will help you greatly on test day, especially in the free-response (FRQ) section. Here, AP graders can give partial credit even if your initial calculations are off, just so long as you show all the steps in your calculations. Here are some other tips to maximize your scores on this section:


  • Don’t skim the question: many FRQ’s have multiple parts. You don’t want to miss out by hastily reading and starting your work.


  • Don’t be vague: whether it’s a calculation or a lab design FRQ, your steps should be organized, logical, and relevant to the question being asked.


  • Don’t interchange terms casually: atoms are not the same thing as molecules and so on.


  • Don’t forget “sig figs”: significant figures can be a pain, but are very important in ensuring an appropriate level of accuracy and precision in your calculations.  


2021 Test Dates

Due to Covid-19, the AP testing timeline has changed somewhat from its normal course. There will be 3 administration periods for all AP exams across May and June:


  • Administration 1 (in school):  May 3–7, 10–12, 14, 17 


  • Administration 2 (digital, in school, or at home):  May 18–21, 24–28


  • Administration 2 (digital, in school, or at home):  June 1-4, 7-11 


Note that schools will decide upon the administration date–students cannot choose. While paper exams follow a local time zone and period as indicated by the school, digital exams start worldwide everywhere at exactly the same time, regardless of time zone.

photo from: College Board site.

Study Resources

There is nothing more comprehensive than the notes that you took in class, but you should always use a prep book. Not only will it help you organize a study plan, but it can also highlight important topics and provide extra practice material. 

If you want information right from the source, visit the College Board site. You can find dates, topics, free-response sample questions/commentary and some helpful exam tips. 


Recommended books

As for recommended books, here are a few that have gotten decent reviews from users. 

  • Excellent: McGraw-Hill 5 Steps to a 5 has 4 practice tests, covers the scope of the test accurately, and explains concepts clearly and understandably.


  • Great: Princeton Review AP Chemistry Prep also has 4 Practice tests. Content is well-organized and questions are consistent in style and difficulty with the exam itself. Some topics, however, are not covered enough in-depth. 


  • Good: Barron’s AP Chemistry has 6 practice tests, but some material is outside the scope of the exam itself. Users have also mentioned that practice questions don’t always reflect actual ones in terms of difficulty (they tend to be more difficult.


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