CHAPTER 23: Reaction Kinetics

CHAPTER  23:  Reaction Kinetics

  • Orders of Reaction and Rate  Equations
  • Reaction Mechanisms
  • Catalysis

 

Learning outcomes:

  • explain and use the terms: rate equation, order of reaction, rate constant, half-life of a reaction, rate-determining step
  • construct and use rate equations of the form rate = k[A]m[B](limited to simple cases of single step reactions and of multistep processes with a rate-determining step, for which m and n are 0, 1 or 2), including:
    i) deducing the order of a reaction from concentration-time graphs, by the initial rates method and half-life methods
    ii) deducing, for zero- and first-order reactions, the order of reaction from concentration-time graphs.
    iii) verifying that a suggested reaction mechanism is consistent with the observed kinetics
    iv) predicting the order that would result from a given reaction mechanism (and vice versa).
  • calculating an initial rate using concentration [integrated forms of rate equations are not required]
  • (i) show understanding that the half-life of a first-order reaction is independent of concentration.
    (ii)  use the half-life of a first-order reaction in calculations.
  • calculate a rate constant, for example by using the initial rates or half-lifemethod
  • devise a suitable experimental technique for studying the rate of a reaction, from given information.
  • outline the different modes of action of homogeneous and heterogeneous catalysis, including:
    • the Haber process
    • the catalytic removal of oxides of nitrogen in the exhaust gases from car engines
    • the catalytic role of atmospheric oxides of nitrogen in the oxidation of atmospheric sulfur dioxide.
    • catalytic role of Fe³  in the  I/S2O8² reaction.