AQA and OCR A · Year 13 physical chemistry
Rate equation question generator
Generate fresh initial-rates tables, determine individual reaction orders, write the rate equation, and calculate the rate constant with the correct units.
Initial-rates questions
Build the rate equation from experimental data
Every table follows one rate law. At higher levels, more than one concentration changes between experiments, so you must account for a known order before finding the next one.
Finding orders from initial rates
Use ratios between experiments to determine the power of each concentration term. A zero-order reactant does not affect the rate, a first-order reactant changes the rate by the same factor as its concentration, and a second-order reactant changes the rate by the square of that factor.
Challenge and master questions change more than one concentration at once. Find one order first, account for its effect on the rate, then use the remaining change to find the next order.
AQA and OCR A coverage
AQA and OCR A both cover initial rates, rate equations, overall order, rate constants and units. Half-life evidence appears only in the OCR A mode of the Order Detective.
Rate Equation Order Detective
Deduce orders from concentration changes, graph descriptions, units of k and OCR-only half-life clues.
Open the detective game → Related calculationArrhenius equation practice
Calculate activation energy or a rate constant using logarithmic forms of the Arrhenius equation.
Practise Arrhenius → Visual modelBoltzmann distribution
Explore how temperature and catalysts change the fraction of particles able to react.
Open the simulator →