Chemical Kinetics

• Introduction & Rate of Reaction

  • Definition of Chemical Kinetics
  • Rate of Reaction ($\Delta R / \Delta t$)
    • Average Rate
    • Instantaneous Rate ($dx/dt$)
  • Units of Rate of Reaction (mol L⁻¹ s⁻¹)
  • Factors Influencing Rate of Reaction
    • Concentration
    • Temperature
    • Catalyst
    • Nature of Reactants & Surface Area

• Rate Law and Order of Reaction

  • Rate Expression & Rate Constant ($k$)
  • Order of Reaction
    • Zero Order
    • First Order
    • Second Order
    • Pseudo First Order Reaction
  • Units of Rate Constant ($k$) for different orders
  • Molecularity of a Reaction
    • Difference between Order and Molecularity

• Integrated Rate Equations

  • Zero Order Reactions
    • Equation: $[R] = [R]_0 - kt$
    • Half-life ($t_{1/2} = [R]_0 / 2k$)
  • First Order Reactions
    • Equation: $k = \frac{2.303}{t} \log \frac{[R]_0}{[R]}$
    • Half-life ($t_{1/2} = 0.693 / k$)
  • Graphical Representation for Zero and First Order

• Temperature Dependence & Arrhenius Equation

  • Effect of Temperature on Reaction Rate
  • Temperature Coefficient ($k_{t+10} / k_t \approx 2 \text{ to } 3$)
  • Arrhenius Equation ($k = A e^{-E_a/RT}$)
    • Activation Energy ($E_a$)
    • Frequency Factor ($A$)
  • Logarithmic Form: $\log \frac{k_2}{k_1} = \frac{E_a}{2.303 R} \left( \frac{T_2 - T_1}{T_1 T_2} \right)$
  • Effect of Catalyst on Activation Energy

• Collision Theory of Chemical Reactions

  • Basic Postulates
    • Effective Collisions
    • Threshold Energy
  • Activation Energy ($E_a$)
  • Orientation Factor / Steric Factor ($P$)
  • Rate Equation: Rate $= P Z_{AB} e^{-E_a/RT}$