What’s Tested on the MCAT: The Chemistry and Physics Section
The MCAT (Medical College Admission Test) is known for testing a wide range of subjects critical to medical school readiness. Among the four sections, the Chemical and Physical Foundations of Biological Systems section, often called the “Chem/Phys” or “CP” section, is particularly challenging. This section assesses your knowledge of chemistry, physics, and biochemistry concepts, as well as your ability to apply this knowledge in a medical context. In this article, we’ll break down what’s tested, the format of this section, key content areas, and how to prepare effectively.
What is Tested on the MCAT Chem/Phys Section?
The Chem/Phys section of the MCAT tests a combination of foundational scientific concepts and critical reasoning skills. It covers five major subject areas:
- General Chemistry
- Organic Chemistry
- Biochemistry
- Physics
- Biology
Each of these subjects plays a role in assessing your understanding of chemical and physical processes that underlie biological systems, as well as your ability to integrate and apply scientific principles to solve complex problems.
Test Format and Question Types
The Chem/Phys section is structured with a mix of passage-based questions and discrete questions:
- 44 Passage-Based Questions: These questions test your ability to interpret data, analyze experiments, and apply foundational knowledge within a scientific context.
- 15 Discrete Questions: These stand-alone questions assess specific content knowledge directly, without the need for contextual interpretation.
Understanding the format and practicing both question types will be key to mastering this section.
Additional reading: Understanding the Components of Your MCAT Score Report
Key Content Areas
General Chemistry
General chemistry concepts form the backbone of the Chem/Phys section. Expect questions on:
- Atomic Structure and Properties
- Chemical Reactions and Stoichiometry
- Thermodynamics and Thermochemistry
- Chemical Kinetics and Equilibrium
- Solutions and Solubility
- Acids and Bases
- Electrochemistry
These topics test your understanding of how chemical reactions occur, how energy is transferred, and how substances interact on a molecular level.
Organic Chemistry
Organic chemistry plays an important role, especially in understanding biologically relevant molecules and reactions. Topics include:
- Structure and Function of Organic Molecules
- Organic Reactions and Mechanisms
- Biologically Relevant Molecules
- Spectroscopy and Analysis
Mastering these concepts will help you interpret reaction mechanisms and analyze molecular interactions critical to biological systems.
Biochemistry
Biochemistry links chemical principles to biological processes. Key areas include:
- Protein Structure and Function
- Enzyme Structure and Kinetics
- Metabolic Pathways and Regulation
- Lipid and Carbohydrate Metabolism
- Nucleic Acids and Genetic Information Flow
Understanding these topics is crucial for interpreting biochemical pathways and their regulation in living organisms.
Physics
Physics concepts are applied to biological systems in the MCAT. Essential topics include:
- Mechanics: Motion, Forces, Energy, and Momentum
- Electricity and Magnetism
- Waves and Optics
- Fluids and Solids
- Thermodynamics in Physical Systems
These concepts test your ability to apply physical principles in biological contexts, such as fluid dynamics in blood circulation or electrical properties in neural transmission.
Biology
Though primarily focused on chemistry and physics, the section does touch on key biology topics:
- Cell Structure and Function
- Molecular Biology and Genetics
- Organ Systems and Homeostasis
These topics assess your understanding of how physical and chemical processes support biological functions.
Additional reading: What’s Tested on the MCAT: The Biology Section
Scientific Inquiry and Reasoning Skills
Success in the Chem/Phys section requires more than memorizing facts; it demands critical thinking skills. The AAMC outlines four key critical thinking abilities essential for success on the MCAT, referred to as Scientific Inquiry and Reasoning Skills SIRS. The exam tests your ability to:
- Apply scientific concepts and principles
- Use scientific reasoning and problem-solving
- Evaluate research design and execution
- Analyze data-based and statistical reasoning
These skills are essential for interpreting scientific literature, designing experiments, and solving complex problems in medical contexts. In addition, these skills are assessed throughout all the science-focused sections of the MCAT, which include the Chemical and Physical Foundations of Biological Systems, Biological and Biochemical Foundations of Living Systems, and Psychological, Social, and Biological Foundations of Behavior.
Additional reading: Why is the MCAT Difficult for Science Students?
Mathematical Concepts and Techniques
Math plays an important role in solving problems on the MCAT, particularly in the Chem/Phys section. You’ll need a strong grasp of:
- Understanding scales and calculating slopes
- Significant digits and numerical estimates
- Metric units and conversions
- Arithmetic calculations: ratios and percentages
- Algebra, exponentials, logarithms, and trigonometry
- Vector addition and subtraction
While calculus isn’t required, mastering these math skills is crucial for accurately answering quantitative questions. And you have to do all the basic math without a calculator.
Distribution of Questions
The distribution of questions by discipline gives you insight into what areas to prioritize in the Chem/Phys section:
- Biochemistry: 25%
- Introductory Biology: 5%
- General Chemistry: 30%
- Organic Chemistry: 15%
- Introductory Physics: 25%
This breakdown highlights the importance of chemistry and physics, but also the crucial role biochemistry plays in the section.
Study Strategies
To maximize your performance, here are some effective study strategies:
- Create an MCAT Study Schedule: Plan out your study sessions and stick to a consistent schedule.
- Focus Review on High-Yield Topics: Prioritize topics with the highest weight in the section.
- Utilize Active Learning Techniques: Engage with the material through practice questions, flashcards, and teaching others.
- Strengthen Problem-Solving Skills: Practice applying concepts to complex scenarios rather than just memorizing facts.
- Review and Adapt Study Plans: Regularly evaluate your progress and adjust your study strategy as needed.
Frequently Asked Questions
Do I need to know…
Q: Do I need to know how to take logs in my head?
A: Yes, but not with much precision. +/- 0.5 units is usually sufficient.
Q: Do I need to know common sin, cos, and tan values?
A: Yes: trig values of of 0, 30, 45, 60, and 90 degrees (and how the patterns beyond those values)
Q: Do I need to know all the equations?
Yes-ish. There are many fundamental equations that you need to know. Obscure equations would be provided for you.
Q: Do I need to know all the constants?
No-ish. Most constants will be given to you. The constants that you do need to have memorized can be found [link].
Q: How do I balance reviewing content with practicing questions?
A: Start with content review, then gradually increase practice questions as your understanding solidifies. Don’t worry about learning every detail in your content review. If you’re missing important ideas, your practice questions will bluntly inform you!
The Chemistry and Physics section of the MCAT can be daunting, but with the right preparation, it’s manageable. Focus on understanding foundational concepts, refining your reasoning skills, and honing your problem-solving techniques. Stay consistent, trust your study plan, and you’ll be well-prepared to tackle this challenging section of the MCAT.
