Chem 1A Ch14

  1. Chemical Kinetics
    The study of the speeds (or rates) of chemical reactions.
  2. Rate of reaction
    The rate of reaction for a given chemical change is the speed with which the reactants disappear and the products form.
  3. What are the five principal factors that influence reaction rates?
    • 1. Chemical nature of the reactants themselves.
    • 2. Ability of the reactants to come in contact with each other.
    • 3. Concentrations of the reactants.
    • 4. Temperature.
    • 5. Availability of rate-accelerating agents called catalysts.
  4. Homogeneous reactions
    Reactions in which all of the reactantsare in the same phase (liquide, solid, gas).
  5. Heterogeneous reactions
    Reactions where the reactants are in different phases (liquide, solid, gas).
  6. Catalyst
    Substances that increase the rates of chemical reactions without being used up.
  7. Rate
    Change in quantity per unit time.
  8. Rate with respect to X
    • = (conc. of X at time tf - conc. of X at time ti) / (tf - ti)
    • = [Delta (conc. of X)] / (Delta t)
  9. Molarity as a rate
    mol / L*s
  10. Rate of reaction
    • Rate = - (Delta [substance]) / (Delta t)
    • note: negitive for reactants, not for products.
  11. Instantaneous rate
    • The slope at that point in time in which either the reactants are being consumed or the product is being created. The value is using the slope formula of
    • (Y1 - Y2) / (X1 - X2)
  12. rate law
    • rate = k [A]m [B]n
    • note: k is called the rate constant.
  13. order of the reaction
    An exponent in the rate law with respect to the corresponding reactant.
  14. First - order reaction
    • rate = k [A]
    • ln ([A]o / [A]t) = kt
    • [A]t = [A]o e -kt
Card Set
Chem 1A Ch14
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