General chemistry is a foundational prerequisite for virtually every health professions program and a significant component of the MCAT®, DAT®, OAT®, and PCAT®. The concepts you learn in general chemistry, from atomic structure to thermodynamics to equilibrium, reappear throughout organic chemistry, biochemistry, pharmacology, and clinical medicine. This guide covers the key topics, free study resources, and strategies for mastering a subject that many pre-health students find challenging.
Key Topics to Master
Atomic Structure and Periodicity: Electron configuration, orbital theory, periodic trends (electronegativity, ionization energy, atomic radius, electron affinity), and how electronic structure determines chemical behavior. Understanding periodicity helps you predict bonding patterns, reactivity, and the properties of elements commonly encountered in biochemistry and pharmacology.
Chemical Bonding: Ionic bonds, covalent bonds, metallic bonds, Lewis structures, VSEPR theory, molecular geometry, bond polarity, and intermolecular forces (hydrogen bonding, dipole-dipole, London dispersion). These concepts are essential for understanding molecular shape, which directly affects drug-receptor interactions and protein structure. Know how to predict molecular geometry and polarity from Lewis structures.
Stoichiometry and Solutions: Mole calculations, limiting reagents, percent yield, solution concentration (molarity, molality, percent composition, dilution), and colligative properties (boiling point elevation, freezing point depression, osmotic pressure). Colligative properties are clinically relevant for understanding IV fluid administration and osmotic disorders.
Thermodynamics and Thermochemistry: First and second laws of thermodynamics, enthalpy, entropy, Gibbs free energy, Hess’s law, bond energies, and calorimetry. Understand the relationship between Gibbs free energy change and reaction spontaneity. These concepts reappear extensively in biochemistry (metabolic pathway energetics, ATP hydrolysis, coupled reactions).
Chemical Kinetics: Reaction rates, rate laws, rate-determining steps, activation energy, catalysis, and the Arrhenius equation. Kinetics is directly relevant to enzyme kinetics in biochemistry (Michaelis-Menten kinetics, enzyme inhibition). Understanding how catalysts lower activation energy prepares you for studying enzyme function.
Chemical Equilibrium: Equilibrium constants (Keq, Kp, Ksp, Ka, Kb), Le Chatelier’s principle, ICE tables, and common ion effect. Equilibrium concepts are essential for understanding acid-base chemistry, buffer systems, solubility, and the Henderson-Hasselbalch equation, all of which have direct clinical applications (blood pH regulation, kidney function, drug solubility).
Acids, Bases, and Buffers: Bronsted-Lowry and Lewis acid-base definitions, pH calculations, strong vs. weak acids and bases, buffer systems, Henderson-Hasselbalch equation, and titration curves. Blood buffer systems (bicarbonate, phosphate, protein) are among the most clinically important applications of general chemistry. Acid-base physiology appears on every health professions licensing exam.
Electrochemistry: Oxidation-reduction reactions, galvanic cells, electrolytic cells, standard reduction potentials, and the Nernst equation. Electrochemistry concepts reappear in biochemistry (electron transport chain, oxidative phosphorylation) and in understanding biological redox reactions.
Gas Laws: Ideal gas law, Dalton’s law of partial pressures, Graham’s law of effusion, and real gas behavior. Partial pressures are directly relevant to respiratory physiology (alveolar gas exchange, oxygen and carbon dioxide transport). Understanding gas laws at a conceptual level is more important for the MCAT® than memorizing equations.
Free Study Resources
Khan Academy® (Free): Khan Academy® provides comprehensive general chemistry content covering all major topics with video lessons and practice exercises. The content aligns well with both coursework and standardized exam preparation. See our Khan Academy® guide.
OpenStax Chemistry (Free): OpenStax publishes a free college chemistry textbook that covers all standard general chemistry topics at a level appropriate for pre-health students. See our free textbooks page.
Anki Flashcard Decks (Free): Community-created chemistry decks cover key constants, equations, periodic trends, and reaction types. See our spaced repetition guide.
Study Strategies
Practice Problems Daily: General chemistry is a problem-solving course. Reading the textbook without doing problems is like reading about swimming without getting in the water. Do 10 to 20 practice problems per study session, covering a mix of topics. Focus on understanding the setup and reasoning, not just getting the right answer.
Connect to Biology and Medicine: Whenever you learn a chemistry concept, ask how it applies to biology or medicine. Buffers connect to blood pH. Equilibrium connects to enzyme kinetics. Electrochemistry connects to cellular respiration. These connections make the chemistry more meaningful and improve retention. See our biochemistry guide for how these topics integrate.
Master the Math: General chemistry requires comfort with algebra, logarithms, scientific notation, and unit conversions. If math is a weakness, invest time early in the semester to build these skills. Math anxiety in chemistry is often actually algebra anxiety, and it is addressable with targeted practice.
For exam-specific preparation, see our guides for the MCAT®, DAT®, and OAT®.
Nuclear Chemistry: Radioactive decay types (alpha, beta, gamma, positron emission, electron capture), half-life calculations, nuclear fission, and nuclear fusion. Nuclear chemistry is relevant to understanding medical imaging (PET scans, SPECT scans), radiation therapy, and radiation safety. Know how to calculate remaining activity after multiple half-lives.
Common Pitfalls in General Chemistry: Many students struggle with unit conversions, significant figures, and setting up ICE tables correctly. Practice these mechanical skills until they are automatic so you can focus your cognitive energy on the conceptual aspects of problems. Another common pitfall is confusing thermodynamic favorability (spontaneity) with kinetic speed; a reaction can be thermodynamically favorable but kinetically slow, and vice versa. Catalysts affect kinetics but not thermodynamics.
How General Chemistry Connects to Clinical Medicine: IV fluid administration involves understanding solution concentration, osmolality, and colligative properties. Blood gas interpretation requires understanding acid-base equilibrium and the Henderson-Hasselbalch equation. Renal physiology involves solubility product constants and saturation. Pharmacokinetics uses first-order kinetics and half-life calculations. Every major area of general chemistry has direct clinical applications, which is why this course remains a universal prerequisite for health professions programs.
Using Practice Exams: After completing each unit in your general chemistry course, take a timed practice exam to simulate test conditions. Analyze your errors to determine whether they are conceptual (you do not understand the material), procedural (you understand the concept but make errors in setup or calculation), or time-related (you run out of time). Each error type requires a different study correction. See our test-taking strategies guide for more on error analysis.
Effective Use of Practice Problems: General chemistry requires daily problem-solving practice. After studying each concept, solve at least 15 to 20 problems of varying difficulty. Start with straightforward calculation problems to confirm you understand the mechanics, then move to conceptual questions that ask you to predict outcomes, explain trends, or apply principles to unfamiliar scenarios. The MCAT® heavily favors conceptual application over straightforward calculation, so make sure your practice includes both types. Keep an error log where you record each problem you got wrong, the correct approach, and the concept you missed. Review this log weekly using spaced repetition principles.
Building a Formula Sheet: Create your own formula sheet organized by topic. For each equation, write a brief description of what it calculates, when to use it, and what each variable represents. Building the sheet yourself (rather than using a pre-made one) forces you to engage actively with the material. Use this sheet during practice and gradually wean yourself off it as you internalize the equations. By exam time, you should be able to recall the key equations from memory, but the act of building the sheet helps you get there.
References
Khan Academy. “Chemistry.” Khan Academy, 2025. https://www.khanacademy.org/science/chemistry. Accessed March 2026.
OpenStax. “Chemistry 2e.” Rice University, 2025. https://openstax.org/details/books/chemistry-2e. Accessed March 2026.
AAMC. “MCAT Content Outline.” AAMC, 2025. https://students-residents.aamc.org/mcat-exam. Accessed March 2026.