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Chemistry definitions, clearly explained.
{{TERMS}} chemistry terms and definitions in one place, written for students, teachers, and the endlessly curious. Build your chemistry vocabulary the clear way: answer first, then the detail, an example, key facts, and the questions people actually ask.
Chemistry terminology by branch
Every term is filed under the branch of chemistry it belongs to, so you can wander a subject or jump straight to a definition.
General Chemistry
The core ideas the rest of chemistry builds on. Start here for atoms, elements, compounds, the mole, and how chemical formulas work.
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{{T:physical-chemistry}} termsPhysical Chemistry
The why behind chemical change. How energy, heat, reaction speed, and equilibrium decide what reactions do.
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{{T:analytical-chemistry}} termsAnalytical Chemistry
How chemists find out what a sample is made of, and how much. Titration, spectroscopy, chromatography, and the tools that measure it.
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{{T:inorganic-chemistry}} termsInorganic Chemistry
The chemistry of metals, minerals, and everything not built on carbon chains. Acids and bases, salts, and periodic-table trends.
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{{T:organic-chemistry}} termsOrganic Chemistry
The chemistry of carbon. Hydrocarbons, functional groups, and the reactions that make fuels, plastics, and living things.
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{{T:biochemistry}} termsBiochemistry
The chemistry inside living things. Proteins, enzymes, carbohydrates, fats, and DNA, and the reactions that keep cells running.
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Chemistry terms to know first
The chemistry terms students, teachers, and professionals look up most, each one clearly and accurately defined.
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Chemistry calculators
Interactive tools for the calculations that come up most in class and in the lab. Each one shows its working, explains the formula, and walks through an example.
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