REVIEW

Chemical Kinetics Objectives and skills

Elementary Reactions

• Define rate of reaction, rates of consumption of reactants, formation of products; relate these using stoichiometry.
• Rate Laws: differential and integrated forms
• Define the order of reaction overall, with respect to reaction species
• Experimental measurement methods
• Plots of experimental data in appropriate ways
• Determine the order of reaction from data
• Define and calculate half-life (and natural life time) of reaction
• Relate activation energy with temperature dependence of rate constant
• Examples: Radioactive decay, decomposition of N₂O₅; reactions approaching equilibrium, consecutive reactions.
• Consecutive Reactions

Complex or Composite Reactions

• Interpret the mechanism of a reaction
• Determine rate expressions from a proposed mechanism. [Conversely, propose a mechanism to explain an observed complex rate expression.]
• uni-molecular, bi-molecular, ter-molecular reaction steps
• coupled differential rate equations that result from a mechanism
• Numerical methods of solution for rate equations
• Approximate methods of solution: steady state approximation, equilibrium approximation
• Illustrations: Chain Reactions, Enzyme catalysis, Relaxation Methods
• Oscillating Reactions. Example: the Lotka mechanism

Problem Solving Methods

• Use initial rates from given initial concentrations to find the order of reaction with respect to reactants. A general approach uses logs of differential rate expression and resulting linear equations to solve for unknown orders.
• Linear least squares fitting (also called linear regression) allows you to
  determine order and rate constants of elementary reactions by plots of ln([X]) vs time (for first order), 1/[X] vs time (for second order), or other;
  to find Michaelis-Menten parameters from plots of 1/v vs 1/[S], or other.
• Complex rate expressions can often be integrated with MathCad's rkfixed function.