Rates of reaction
6.1.1 Define the term rate of reaction.
6.1.2 Describe suitable experimental procedures for measuring rates of reactions.
TOK: The empirical nature of the topic should be emphasized. Experimental results can support the theory but cannot prove it.
6.1.3 Analyse data from rate experiments.
Collision theory
6.2.1 Describe the kinetic theory in terms of the movement of particles whose average energy is proportional to temperature in Kelvin.
6.2.2 Define activation energy, Ea.
6.2.3 Describe the collision theory.
6.2.4 Predict and explain, using the collision theory, the qualitative effects of particle size, temperature, concentration and pressure on the rate of a reaction.
6.2.5 Sketch and explain qualitatively the Maxwell–Boltzman energy distribution curve for a fixed amount of gas at different temperatures and its consequences for changes in reaction rate.
6.2.6 Describe the effect of a catalyst on a chemical reaction.
6.2.7 Sketch and explain Maxwell– Boltzmann curves for reactions with and without catalysts.
Rate expression
16.1.1 Distinguish between the terms rate constant, overall order of reaction and order of reaction with respect to a particular reactant.
16.1.2 Deduce the rate expression for a reaction from experimental data.
16.1.3 Solve problems involving the rate expression.
16.1.4 Sketch, identify and analyse graphical representations for zero-, first- and second-order reactions.
Reaction mechanism
16.2.1 Explain that reactions can occur by
more than one step and that the slowest step determines the rate of reaction (rate-determining step).
16.2.2 Describe the relationship between reaction mechanism, order of reaction and rate-determining step.
TOK: Agreement between rate equation and a suggested mechanism only provides evidence to support a reaction mechanism. Disagreement disproves the mechanism.
Activation energy
16.3.1 Describe qualitatively the relationship between the rate constant (k) and temperature (T).
16.3.2 Determine activation energy (Ea) values from the Arrhenius equation by a graphical method.
