Rates of Reaction

The resources in this list cover rates of reaction, how they can be measured, and what factors affect the rate of a chemical reaction.

Students need to understand how the rate of a chemical reaction can be measured in terms of the rate of production of a product or the rate of consumption of a reactant. Students also need to be able to describe simple methods of measuring mass loss if a gaseous product is allowed to escape, volume of gas produced , change in colour, change in pH, or change in turbidity if a precipitate is produced.

Students should be able to produce graphs of amount of species (as mass, volume or some relative quantity) against time and understand that the gradient to the curve at any point in time represents the rate of reaction at that time.

Higher tier students need to be able to use concentration as the measure of amount of species and calculate the numerical value of the gradient at a point on the curve.

Students need to be able to identify factors that affect the rate of a chemical reaction and to predict and explain the effect of changing a factor using collision theory.

Students should represent reactions and reaction profiles and clearly identify the activation energy and enthalpy change, and be able to sketch a suggested profile for a catalysed reaction on the uncatalysed profile to show the difference.

Whilst this list provides a source of information and ideas for experimental work, it is important to note that recommendations can date very quickly. Do NOT follow suggestions which conflict with current advice from CLEAPSS, SSERC or other recent safety guides. eLibrary users are responsible for ensuring that any activity, including practical work, which they carry out is consistent with current regulations related to Health and Safety and that they carry an appropriate risk assessment. Further information is provided in our Health and Safety guidance