If you're seeing this message, it means we're having trouble loading external resources for Khan Academy.

If you're behind a web filter, please make sure that the domains *.kastatic.org and *.kasandbox.org are unblocked.


Videos on chemistry (roughly covering a first-year high school or college course).
Community Questions

Atoms, Molecules, and Ions

Atomic structure, Atomic numbers, Atomic Mass, Moles, Ions (eventually), Compounds (eventually)

Chemical Reactions and Stoichiometry

We are now going to delve into the heart of chemistry. We learn ways of representing chemical molecules and how molecules react. To do this, we'll even think about "how many" of a molecule we have using a quantity called a "mole".

Electronic Structure of Atoms

Bohr model, Absorption, Emission Spectrum, Quantum numbers, Electron Configurations

The Periodic Table

Classification of elements, Atomic radii, Ionic radii, Ionization energy, Electron Affinity

Chemical Bonds

Ionic Bonds, Metallic Bonds, Covalent Bonds, Electronegativity, Molecular Geometry

Gases and Kinetic Molecular Theory

Gas Laws (eventually), Ideal Gas Equation, Dalton's Law (eventually), Kinetic Molecular Theory (eventually)

States of Matter and Intermolecular Forces

Intermolecular Forces, Liquids, Solids, Phase Changes

Chemical Equilibrium

Equilibrium Constant, Heterogeneous Equilibria, Le Chatelier's Principle

Acids and Bases

Definitions, pH, Strong and Weak Acids and Bases, Acid-Base Equilibrium, Salt Solutions

Acid-Base Equilibria and Solubility Equilibria

Common-ion effect, Buffer solutions, Titrations, Solubility Equilibria

Redox Reactions and Electrochemistry

Oxidation states (numbers), Oxidation-Reduction (Redox) reactions, Galvanic/Voltaic Cells, Electrolytic Cells


Reaction Rates, Rate Laws, The Arrhenius Equation, Catalysts

Nuclear Chemistry

Nuclear reactions, Nuclear stability, Radioactive Decay