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Physical chemistry

Seven lessons on why reactions happen, how far and how fast: heat and enthalpy, Hess’s law, entropy and Gibbs energy, equilibrium constants and Le Chatelier, rate laws, half-lives and the Arrhenius equation, and vapor pressure and Raoult’s law, which is where distillation starts.

Part of the Chemical engineer path.

Take first: General chemistry.

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How it works

Each lesson is a short read with worked examples, then a few practice questions. Some ask you to work out a number (grams, moles, kelvin, kilowatts), some have you pick an answer, and some have you tap steps into the right order. Keep a calculator handy; the question says how to round. You can try again as often as you like; after two misses there’s a button to show the answer. Where a lesson has one, the Particle Lab experiment lets you watch the idea happen with atoms and molecules.

What do I need to know first?

General chemistry helps. The first lesson recaps moles, kelvin and the gas constant, and the logs and powers of ten the formulas use. A calculator with ln and eˣ keys helps.

The other chemistry and chemical engineering courses

Where is my progress saved? In this browser, like the rest of the site. Nothing to sign up for.

For learning only. It isn’t lab safety training, an accredited qualification or engineering advice: real lab work and plant design follow your organization’s safety procedures, the safety data sheets and the codes that apply where you are. Worked numbers use rounded values and simple models, so check real designs against proper data.