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 ($<br>rate = \frac{\Delta C}{\Delta T}$).

Reaction Rate Calculation

• Expressed commonly in M/s.

• Based on initial (i) and final (f) concentrations ($\text{Rate} = \frac{C<em>f - C</em>i}{T<em>f - T</em>i}$).

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