Learn chemistry
Short lessons that explain a concept from the start, then let you practise it — you try first, and the tool tells you what's wrong rather than handing over the answer. Plus quick reference for the periodic table and the constants you'll need.
Every reaction, listed
All 289 reactions in the sandbox with their balanced equations and reaction type — searchable and filterable by category, plus the special mechanisms and the deliberate no-reaction cases.
referenceThe mole & molar mass
What a mole actually is, relative atomic mass, and how to calculate molar mass — worked examples for H₂O, CaCO₃ and Ca(NO₃)₂, then practice questions you check yourself.
lesson + practiceBalancing chemical equations
Why atoms must balance, the step-by-step method with a worked example, then 130+ equations to balance yourself — the tool tells you which elements are still off and by how much.
lesson + practiceAtomic models
Dalton, Thomson, Rutherford (the gold-foil experiment), Bohr and the quantum model — each with its theory, the experiment behind it, an animated diagram, and why it changed.
explainerMemorize the periodic table
Mnemonic sentences for the elements in order — one per period and one per group. Tap any word to open that element, and hide the symbols to test yourself.
mnemonicsChemistry constants
Avogadro's number, the gas constant R (in every unit), the Faraday constant, molar volume at STP and SATP, and more — with a note on where each one is used.
referenceInteractive periodic table
All 118 elements, recoloured by category, block, state, radioactivity or origin. Click any element for its data and a rotating Bohr diagram.
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