Work through the list without notes. If you cannot do a statement, follow its link, then come back. Guide = study guide; Practice = practice questions.
Understanding
- I can say when the slow step’s rate law is the final answer and when it is not. (Guide: “When the slow step is not the first step”; Practice Q7)
- I can explain why an intermediate must not appear in the rate law of a reaction. (Guide; Practice Q1, Q7)
- I can explain, in terms of particles, why a fast reversible first step stays close to equilibrium while a later step is slow. (Guide: “The idea”; Practice Q7)
- I can explain why steps after the slow step do not affect the rate law. (Guide: “The pre-equilibrium recipe”; Practice Q7)
Skills
- I can write the forward and reverse rates of a fast step and set them equal to find the intermediate’s concentration, with the forward constant on top. (Guide: “The algebra in three lines”; Practice Q2)
- I can derive a rate law with a pre-equilibrium, showing the slow step, the equilibrium expression and the substitution. (Guide: Worked example 1; Practice Q1, Q4)
- I can derive a half-order rate law when a molecule splits in the fast step. (Guide: Worked example 2; Practice Q3)
- I can combine step constants into an overall rate constant and give its units. (Guide: Worked example 2; Practice Q4)
- I can calculate a rate, and the intermediate’s concentration, from step rate constants and reactant concentrations. (Practice Q4)
- I can show how a catalyst can appear in a rate law through a fast first step. (Practice Q6)
Reasoning
- I can find orders from initial-rate data and decide which proposed mechanisms are consistent with them. (Practice Q5)
- I can explain why a matching rate law supports a mechanism without proving it. (Guide: Worked example 1; Practice Q5)
All ticked? Move on to Topic 5.10, Multistep Reaction Energy Profile, or return to the course roadmap.