A line tells a story
Connect an equation, a table and a graph—and explain what changes and what stays fixed.
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16 lesson found. This published collection is growing and is not a complete syllabus. Browse all registered public topics.
The particles do not melt
Explain a change of state using what we observe, what particles do and the symbols we write.
Open the complete free lessonDifferent pieces, the same fraction
Explain equivalence using equal-sized parts of the same whole, compare fractions and recognise fractions greater than one.
Open the complete free lessonPercent of what? Find the base first
Connect fractions, decimals and percentages, find a percentage of a quantity and distinguish an increase from the final amount.
Open the complete free lessonSolve an equation without losing the balance
Translate a word sentence into an equation, preserve equality through inverse operations and verify a solution.
Open the complete free lessonA ratio compares parts; a fraction names a whole
Distinguish part-to-part and part-to-whole comparisons, share a total in a ratio and connect the result to a percentage.
Open the complete free lessonTwo equations, one common solution
Use elimination and substitution to find a pair that satisfies two equations and verify both conditions.
Open the complete free lessonIndices describe structure, not shortcuts
Derive index laws from repeated factors and interpret zero, negative and fractional powers with their domain restrictions.
Open the complete free lessonRead a quadratic through its roots
Derive the sum and product of roots from factor expansion, form a quadratic and use root relationships in a transfer problem.
Open the complete free lessonTwo percentage changes do not simply cancel
Model successive percentage changes with multipliers, distinguish simple and repeated growth and verify the base at every step.
Open the complete free lessonCount particles without changing the element
Use atomic and mass numbers to count protons, neutrons and electrons, and explain why making an ion does not change element identity.
Open the complete free lessonCharged particles need a path to conduct
Distinguish ion formation from ionic bonding, use charge balance to write a formula and explain solid versus molten conductivity.
Open the complete free lessonBalance atoms, preserve the substances
Balance an equation by changing coefficients, count every atom and distinguish an amount ratio from a mass ratio.
Open the complete free lessonThe mole connects a balance to particles
Calculate a compound's molar mass, convert between grams and moles with units and distinguish amount from a particle count.
Open the complete free lessonNeutralisation: follow the reacting ions
Represent a dilute strong-acid/strong-base neutralisation, identify spectator ions and calculate reacting amounts with correct volume units.
Open the complete free lessonA chromatogram is evidence, not a barcode
Calculate dimensionless Rf values from a common baseline and judge what a chromatogram can and cannot establish.
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