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Material and energy balances

Seven lessons on accounting for every kilogram and kilojoule in a process, the first skill of a chemical engineer: units and flow rates, balances on mixers, evaporators and distillation columns, recycle, bypass and purge, reacting systems, combustion and excess air, and energy balances with steam heating and heats of reaction.

Part of the Chemical engineer path.

Take first: General chemistry, Physical 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?

The chemistry courses help, General chemistry most of all. The first lesson recaps the moles, equations and heat the rest uses. A calculator is enough; there's no calculus.

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.