Reactions & Stoichiometry
Empirical and Molecular Formulas
How do you find an empirical formula?
Chemistry made simple
Chemistry, made clear.
Clear, visual explanations of the chemistry concepts students find hardest, with worked examples, flashcards and quizzes so you can check you really understand.
For high-school, college and university students, and the teachers who help them.
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- FoundationsMatter, measurement, units and the core vocabulary of chemistry.Coming soon
- Atomic Structure & PeriodicityWhat atoms are made of, how electrons are arranged, and the patterns of the periodic table.Coming soon
- Bonding & Molecular StructureHow atoms hold together, the shapes of molecules, and the forces between them.Coming soon
- Reactions & StoichiometryChemical formulas and equations, the mole, and calculating amounts in reactions.3 lessons
- States of Matter & GasesSolids, liquids and gases, and the relationships that describe gas behaviour.Coming soon
- SolutionsDissolving, concentration, and how solutions are prepared and described.Coming soon
- Acids & BasesAcids, bases, pH, neutralisation and buffers.Coming soon
- Thermochemistry & ThermodynamicsEnergy changes in chemistry and what makes reactions happen.Coming soon
- KineticsHow fast reactions go and what controls their rate.Coming soon
- EquilibriumReversible reactions and the balance they reach.Coming soon
- Redox & ElectrochemistryElectron transfer, oxidation states, cells and electrolysis.Coming soon
- Nuclear ChemistryChanges in the nucleus, radioactivity and their uses.Coming soon
- Organic ChemistryCarbon compounds — structures, names, functional groups and reactions.Coming soon
- Analytical ChemistryHow chemists measure and identify substances — titration, spectroscopy and chromatography.Coming soon
The Chemistry Clarity method
Every lesson follows the same clear path
Complex chemistry → simple explanation → visual understanding → practice → mastery.
What is it?
A plain-language definition, without unexplained jargon.
Why does it matter?
Where the idea shows up and why it is worth learning.
How does it work?
A clear, step-by-step explanation of the reasoning.
Visualise it
Diagrams, illustrations and analogies that make it click.
Worked example
Every step shown, so you can follow and repeat it.
Common mistake
What students often get wrong, and how to avoid it.
Remember this
The key takeaway in one or two lines.
Test yourself
Flashcards, practice questions and quizzes.
New
Latest lessons
Reactions & Stoichiometry
Formula Mass and Percent Composition
How do you calculate percent composition?
Reactions & Stoichiometry
The Mole Concept
What is a mole in chemistry?
Simple, but never careless
Simplifying chemistry is useful; getting it wrong is not. Every lesson is checked for accuracy, shows when it was last reviewed, and points out where a simplified explanation has limits.
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