Principles of Chemical Science by MIT

About this course

Chemistry can feel like a collection of rules to memorize, but it becomes far more useful when you see the principles connecting everything from materials and energy to biology and the environment. This free online course helps you develop that core understanding, so you can explain chemical behavior instead of guessing it. You will learn to think like a chemist: interpret models, relate microscopic structure to macroscopic properties, and use quantitative reasoning to predict what happens in real systems.

You begin by building a solid foundation in atomic structure and the wave-particle ideas that underpin modern chemistry. From there, the course makes the leap from single-electron pictures to multielectron atoms and periodic trends, helping you understand why elements behave the way they do and how electron configuration drives reactivity. As the ideas deepen, you connect structure to bonding through Lewis structures, formal charge, resonance, VSEPR shapes, and the complementary viewpoints of valence bond theory, hybridization, and molecular orbital theory.

With structure in place, you move into the energetic and directional nature of chemical change. You will use thermodynamics to reason about enthalpy, entropy, and Gibbs free energy, making sense of why reactions release or absorb heat and what really determines spontaneity. You then apply the same logic to chemical equilibrium, learning how systems respond to stress and how tools like Le Châtelier’s principle guide predictions in industrial and everyday contexts.

Acid-base chemistry and solubility build practical intuition for solutions, buffers, salt effects, and titrations, turning pH from a confusing number into a meaningful chemical signal. Redox and electrochemistry connect electron transfer to batteries and biological oxidation, while transition-metal chemistry and crystal field theory explain magnetism and color in coordination complexes. Finally, kinetics and mechanisms show you what controls reaction speed, how temperature shifts rates, and why catalysts matter. Throughout, integrated exercises reinforce each idea so you can practice reasoning under test-like conditions and carry the concepts into your next class, lab, or career goal.