Chemical Reactions and Factors Affecting Rates - CHM 1046

Learning Outcomes

  • Define chemical reaction rate.

  • Determine relative reaction rates from a balanced equation.

  • Calculate reaction rates from experimental data.

  • Analyze graphs to determine reactants/products, reaction rates, and rate changes.

  • Identify parameters influencing reaction rates.

Chemical Kinetics

  • Study of chemical reaction rates (how fast reactions occur).

  • Reaction rate: Change in concentration of reactant or product per unit time (
    rate = \frac{\Delta C}{\Delta T}).

Reaction Rate Calculation

  • Expressed commonly in M/s.

  • Based on initial (i) and final (f) concentrations (\text{Rate} = \frac{Cf - Ci}{Tf - Ti}).

Stoichiometry in Reaction Rates

  • Relative reaction rates depend on stoichiometry of the balanced equation.

  • General form: aA + bB \longrightarrow cC + dD.

  • Rate expressions for reactants/products include negative signs to reflect loss/gain.

Factors Affecting Reaction Rates

  • Nature of reactants: Different properties (e.g., Fe vs. Na).

  • State of reactants: (e.g., powders react faster than larger pieces).

  • Temperature: Higher temperature generally increases reaction rates.

  • Catalysts: Substances that increase reaction rates without being consumed.

  • C