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Chemistry is essentially the study of the behavior of electrons in atoms and molecules. By understanding what the electrons do in various circumstances, we can understand everything about how atoms come together to make molecules, how molecules come together to make materials, and how atoms, molecules and materials interact in reactions.

My friend at Harvard Medical School, a chemist, once told me, "Physics is well and good, but without chemistry, we'd all just be rubbing sticks and rocks together. Chemistry lets us make stuff."

By understanding chemistry, we understand stuff. We understand the details of biology - how cells work, how protein, DNA and RNA interact to form the basis of life on Earth. We understand our planet itself, how materials are made and how their properties can be altered, how pollutants affect the natural environment, and on and on. Everything is chemistry.

chemistry quote

The subjects in the menu above are expanded notes that I've given to my high-school chemistry students over the years as we've learned this amazing science together. One of the most compelling things about chemistry is that there's still so much to figure out. I'll try to point out what we don't know as we go along. Who knows ? Maybe you'll be the one to figure it out.


There are a couple of ways to navigate this site. Use the pull-down menus at the top of the page, or the site map below. Let me know about any dead links or topics you'd like to see added.

Chemistry table of contents

There are many ways to order the subjects when teaching chemistry. This is roughly how I do it, but I've tried to write the sections so that they pretty much stand alone. I'm always happy to hear suggestions about what else to include.

  1. Foundations
    1. Scientific notation
    2. The metric system
    3. Electrons
    4. Atoms
      1. The Rutherford experiment
    5. The periodic table
    6. Chemical notation
    7. Periodic trends
    8. Ions & ionic compounds
    9. Molecules
      1. Covalent bonding
      2. Lewis dot structures
      3. VSEPR (valence shell electron pair repulsion theory)
    10. Quantum theory
  2. Thermodynamics
    1. Heat
    2. Heat transfer (physics)
    3. Conservation of energy
    4. Enthalpy & Thermochemistry
    5. Entropy & Thermochemistry
    6. Colligative properties
    7. Free energy & spontaneity
      1. Gibbs free energy
      2. Helmholtz energy
      3. Chemical potential
    8. Reaction profiles, exothermic, endothermic
  3. Reactions
    1. Equations
    2. Reaction types
    3. Balancing
    4. Moles
    5. Stoichiometry
      1. Basic stoichiometry calculations
      2. Limiting reactant & expected yield
      3. More difficult stoichiometry calculations
      4. VIDEO   Video examples
    6. Oxidation numbers | Oxidation states
    7. Redox balancing
    8. Electrochemistry
      1. Electrochemical cells (batteries)
      2. Electrolysis and plating
      3. Fuel cells
  4. Equilibrium
    1. Concentration
    2. Solubility
    3. Hydrates
    4. Chemical equilibrium
      1. Le Châtelier's Principle
    5. Acids & bases
      1. Buffers
  5. Gases & the gas laws
    1. Pressure defined
    2. Gas laws
    3. Kinetic-molecular theory of gases
    4. The ideal gas law
    5. Non-ideal behavior
  6. Kinetics
    1. Chemical kinetics
    2. Chemical kinetics (calculus)
  7. Intermolecular forces
  8. Organic chemistry
    1. Introduction
    2. Functional groups and naming
  9. Water
  10. Biochemistry
    1. Molecules of life
    2. Proteins
    3. Nucleic acids
    4. Lipids
    5. Carbohydrates

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