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Science

AP®︎/College Chemistry beta

Learn AP Chemistry using videos, articles, and AP-aligned practice. Review the fundamentals of atomic structure, intermolecular forces and bonding, chemical reactions, kinetics, thermodynamics, and equilibrium.

AP®︎/College Physics 2

An algebra-based, introductory college-level physics course that explores topics such as fluid statics and dynamics; thermodynamics with kinetic theory; PV diagrams and probability; electrostatics; electrical circuits with capacitors; magnetic fields; electromagnetism; physical and geometric optics; and a whole lot more.

Cosmology and astronomy

It's a great, big universe out there. In this section of Khan Academy, you'll learn about the brain-bending vastness of time and space. We go from plate tectonics here on Earth to entire galaxies and beyond.

Biology library

Welcome to the Biology library! Biology is the study of life. Here, you can browse videos, articles, and exercises by topic. We keep the library up-to-date, so you may find new or improved content here over time.

A brief introduction to biology

Biology, defined as the scientific study of life, is an incredibly broad and diverse field. In many ways, it's as kaleidoscopic and rich as living organisms themselves. Biologists study life at many scales, from cells to organisms to entire ecosystems. Begin your own biological journey here!
Start learning

A brief introduction to biology

Biology, defined as the scientific study of life, is an incredibly broad and diverse field. In many ways, it's as kaleidoscopic and rich as living organisms themselves. Biologists study life at many scales, from cells to organisms to entire ecosystems. Begin your own biological journey here!
Start learning

A brief introduction to physics

Physics is the study of the basic principles that govern the physical world around us. We'll start by looking at motion itself. Then, we'll learn about forces, momentum, energy, and other concepts in lots of different physical situations. To get the most out of physics, you'll need a solid understanding of algebra and a basic understanding of trigonometry.
Start learning

A brief introduction to physics

Physics is the study of the basic principles that govern the physical world around us. We'll start by looking at motion itself. Then, we'll learn about forces, momentum, energy, and other concepts in lots of different physical situations. To get the most out of physics, you'll need a solid understanding of algebra and a basic understanding of trigonometry.
Start learning

A brief introduction to chemistry

We will be covering the material in a first year introductory high school or college general chemistry course. This may be your first time taking chemistry, but chances are you know a lot of chemistry already from observing the world around you. We will learn how to explain phenomena by thinking in terms of the atoms that make up all matter, and how atoms interact. Basically, learning chemistry is like having telescopic vision!
Start learning

A brief introduction to chemistry

We will be covering the material in a first year introductory high school or college general chemistry course. This may be your first time taking chemistry, but chances are you know a lot of chemistry already from observing the world around you. We will learn how to explain phenomena by thinking in terms of the atoms that make up all matter, and how atoms interact. Basically, learning chemistry is like having telescopic vision!
Start learning