Chemical Kinetics

• Closer Look at Chemical Reaction Process

Slide 1

• Introduction to Chemical Kinetics
• Definition and scope of Chemical Kinetics
• Importance of studying Chemical Kinetics in understanding reaction rates

Slide 2

• Factors affecting the rate of a Chemical Reaction
• Nature of Reactants
• Concentration of Reactants
• Temperature
• Surface Area

Slide 3

• Collision Theory of Chemical Reactions
• Successful collision and activation energy
• Role of effective collisions in reaction rate
• Activation energy and reaction barriers

Slide 4

• Rate of Reaction: Average Rate
• Definition and calculation of average rate of reaction
• Units of rate of reaction
• Determination of reaction rate using changes in concentration

Slide 5

• Rate of Reaction: Instantaneous Rate
• Definition and calculation of instantaneous rate of reaction
• Determination of reaction rate using rate expression

Slide 6

• Integrated Rate Laws
• Zero-Order Reactions
• First-Order Reactions
• Second-Order Reactions

Slide 7

• Determination of Order of Reaction
• Graphical Method
• Method of Initial Rates

Slide 8

• Half-Life of Reactions
• Definition and calculation of half-life
• Relationship between half-life and reaction order

Slide 9

• Rate-Determining Step
• Definition and importance of rate-determining step
• Concept of elementary steps and rate laws

Slide 10

• Collision Theory and Reaction Mechanisms
• Concept of reaction mechanism
• Role of intermediates and catalysts
• Relationship between reaction mechanism and rate law

Slide 11

• Rate Laws and Rate Constants
  • Rate law expression and rate constant
    • k, the rate constant
  • Relationship between rate law and reaction order
• First-Order Reactions
  • Rate law expression for first-order reactions
    • Rate = k[A]
  • Half-life of first-order reactions
    • t1/2 = 0.693/k
• Second-Order Reactions
  • Rate law expression for second-order reactions
    • Rate = k[A]^2 or Rate = k[A][B]
  • Half-life of second-order reactions
    • t1/2 = 1/(k[A]0)
• Zero-Order Reactions
  • Rate law expression for zero-order reactions
    • Rate = k
  • Half-life of zero-order reactions
    • t1/2 = [A]0 / 2k

Slide 12

• Temperature and Rate Constant
  • Effect of temperature on reaction rate
    • Increasing temperature increases rate of reaction
  • Activation energy and Arrhenius equation
    • The role of activation energy in reaction rate
    • Arrhenius equation: k = A * e^(-Ea/RT)
      • k is the rate constant
      • A is the pre-exponential factor
      • Ea is the activation energy
      • R is the gas constant
      • T is the temperature in Kelvin

Slide 13

• Reaction Mechanisms
  • Multistep Reactions
  • Reaction intermediates and rate-determining step
  • Overall rate law and elementary steps
  • Rate expression for each step and overall rate expression
• Elementary Reactions
  • Definition and characteristics of elementary reactions
  • Unimolecular Reactions (A → products)
  • Bimolecular Reactions (A + B → products)
  • Termolecular Reactions (A + B + C → products)

Slide 14

• Catalysts and Reaction Rate
  • Definition and role of catalysts in chemical reactions
  • Catalysts and reaction mechanism
  • Heterogeneous catalysts and surface reactions
  • Enzymes and biological catalysts
• Factors Influencing Reaction Rate
  • Effect of concentration on reaction rate
  • Effect of temperature on reaction rate
  • Effect of catalyst on reaction rate

Slide 15

• Rate Laws and Equilibrium Constants
  • Relationship between rate constants and equilibrium constants
  • Equilibrium constant expression and reaction quotients
  • Relationship between forward and reverse rate constants
• Reversible Reactions and Equilibrium
  • Definition of reversible reactions
  • Forward and reverse reaction rates
  • Equilibrium position and dynamic equilibrium

Slide 16

• Le Chatelier’s Principle
  • Definition and statement of Le Chatelier’s Principle
  • Predicting the effect of changes on equilibrium position
  • Effect of temperature, pressure, and concentration changes
• Factors Affecting Equilibrium Constants
  • Effect of temperature on equilibrium constant
  • Effect of pressure and volume on equilibrium constant
  • Effect of changing concentrations on equilibrium constant

Slide 17

• Solubility Equilibrium and Ksp
  • Definition of solubility equilibrium
  • Solubility product constant (Ksp)
    • Ksp expression and values
  • Common ion effect and precipitation reactions
• Acid-Base Equilibrium and Ka/Kb
  • Definition of acid-base equilibrium
  • Acid dissociation constant (Ka) and base dissociation constant (Kb)
    • Ka expression and values
    • Henderson-Hasselbalch equation

Slide 18

• pH and pOH
  • Definition and calculation of pH and pOH
  • Relationship between pH and pOH
  • Acidic, basic, and neutral solutions
• Buffer Solutions
  • Definition and characteristics of buffer solutions
  • Buffer capacity and buffer range
  • Henderson-Hasselbalch equation for buffer solutions

Slide 19

• Solubility and Complexation Equilibria
  • Solubility product constant (Ksp) and solubility
    • Calculating solubility from Ksp
    • Effect of pH on solubility
  • Complexation equilibrium and stability constant (Kf)
    • Formation constant (Kf) expression and values
    • Determining the formation of complex ions

Slide 20

• Redox Reactions and Electrochemical Cells
  • Oxidation and reduction reactions
    • Redox equations and half-reactions
  • Balancing redox reactions using the Half-Reaction Method
    • Steps for balancing redox reactions
    • Examples of balancing redox reactions
• Electrochemical Cells
  • Definition and components of electrochemical cells
  • Anode, cathode, and salt bridge
  • Cell potential, standard potential, and electrode potentials

Slide 21

• Rate Determination and Rate Laws
  • How to determine the rate law of a reaction
  • Use of initial rates and rate constants
  • Examples of rate determination using experimental data
• Rate Laws and Rate Equations
  • General form of rate equations
  • Use of rate constants
  • Relationship between concentrations and reaction rate
• Rate Laws and Stoichiometry
  • Effect of stoichiometry on rate laws
  • Determination of reaction order
  • Rate laws for complex reactions
• Rate Expression and Rate Constants
  • Rate expression as a function of reactant concentrations
  • Determining rate constants from experimental data
• Examples:
  • Determination of rate law for a reaction: A + B -> C
  • Calculation of rate constant from experimental data

Slide 22

• Reaction Mechanisms and Elementary Steps
  • Definition of reaction mechanisms
  • Elementary steps and overall reaction
  • Role of intermediates in reaction mechanisms
• Reaction Mechanism and Rate Determining Step
  • Rate determining step and overall reaction rate
  • Rate law expression for overall reaction
  • Examples of reaction mechanisms and rate determining steps
• Reaction Mechanism and Activation Energy
  • Relationship between reaction mechanism and activation energy
  • Energy profile diagram for a reaction
  • Role of transition states in reaction mechanism
• Examples:
  • Reaction mechanism of nitric oxide formation
  • Rate determining step in the combustion of methane

Slide 23

• Reaction Order and Rate Constants
  • Determination of reaction order from rate equation
  • Relationship between reaction order and rate constants
  • Examples of reaction order determination
• Rate Laws and Temperature
  • Effect of temperature on rate constants
  • Arrhenius equation and activation energy
  • Calculation of rate constants at different temperatures
• Collision Theory and Activation Energy
  • Basic principles of collision theory
  • Effect of activation energy on reaction rate
  • Relationship between activation energy and rate constant
• Examples:
  • Calculation of rate constant at different temperatures using Arrhenius equation
  • Determination of activation energy from experimental data

Slide 24

• Catalysts and Reaction Rates
  • Definition and role of catalysts in reactions
  • Types of catalysts: homogeneous and heterogeneous
  • Effect of catalyst on activation energy and reaction rate
• Factors Affecting Reaction Rates
  • Concentration of reactants
  • Temperature of the reaction
  • Presence of catalysts
  • Surface area of the reactants
• Catalytic and Non-catalytic Reactions
  • Comparison between catalytic and non-catalytic reactions
  • Examples of catalytic reactions in industry and everyday life
• Examples:
  • Effect of catalyst on reaction rate: decomposition of hydrogen peroxide
  • Influence of reactant concentration on reaction rate: iodine clock reaction

Slide 25

• Rate Laws, Equilibrium Constants, and Le Chatelier’s Principle
  • Relationship between rate constants and equilibrium constants
  • Equilibrium position and reaction rates
  • Le Chatelier’s Principle and its application to reaction rates
• Reversible Reactions and Equilibrium
  • Definitions of reversible reactions and equilibrium
  • Forward and reverse reaction rates at equilibrium
  • Calculation of equilibrium constant from reaction rates
• Solubility Equilibrium and Ksp
  • Definition of solubility equilibrium
  • Solubility product constant (Ksp) and its calculation
  • Common ion effect on solubility equilibrium
• Examples:
  • Calculation of equilibrium constant from reaction rates
  • Determination of solubility product constant for a salt

Slide 26

• Acid-Base Equilibrium and Ka/Kb
  • Acid dissociation constant (Ka) and base dissociation constant (Kb)
  • Calculation of Ka/Kb from acid/base concentrations
  • Relationship between Ka and acid strength, and between Kb and base strength
• pH and pOH
  • Definition and calculation of pH and pOH
  • Relationship between pH, pOH, and concentration of H+ and OH- ions
  • Acidity and basicity of solutions based on pH values
• Buffer Solutions
  • Definition and characteristics of buffer solutions
  • Buffer capacity and buffer range
  • Henderson-Hasselbalch equation for buffer solutions
• Examples:
  • Calculation of pH and pOH of acidic and basic solutions
  • Preparation of buffer solutions and determination of their pH

Slide 27

• Solubility and Complexation Equilibria
  • Solubility product constant (Ksp) and its calculation
  • Calculation of solubility from Ksp values
  • Effect of pH on solubility equilibrium
• Complexation Equilibrium and Stability Constant
  • Formation of complex ions and equilibrium constant (Kf)
  • Calculation of formation constant from reactant concentrations
  • Determination of the formation of complex ions in a reaction
• Redox Reactions and Electrochemical Cells
  • Oxidation and reduction reactions
  • Balancing redox reactions using the Half-Reaction Method
  • Electrochemical cells and cell potentials
• Examples:
  • Calculation of solubility from Ksp values
  • Balancing redox reactions using the Half-Reaction Method

Slide 28

• Factors Affecting Equilibrium Constants
  • Effect of temperature on equilibrium constant
  • Effect of changing concentrations on equilibrium constant
  • Effect of pressure and volume changes on equilibrium constant
• Solubility Equilibrium and Common Ion Effect
  • Definition of solubility equilibrium
  • Common ion effect on solubility of salts
  • Calculation of solubility considering the common ion effect
• Le Chatelier’s Principle
  • Definition and statement of Le Chatelier’s Principle
  • Predicting the effect of changes on equilibrium position
  • Examples of applying Le Chatelier’s Principle
• Examples:
  • Calculation of equilibrium constant considering temperature changes
  • Application of Le Chatelier’s Principle to predict equilibrium shift

Slide 29

• Redox Reactions and Half-Cell Potentials
  • Definition of half-cell potentials and standard potentials
  • Calculation and determination of half-cell potentials
  • Electrochemical series and predicting redox reactions
• Oxidation-Reduction Titrations
  • Definition and process of oxidation-reduction titrations
  • Examples of oxidation-reduction titrations
  • Calculation of unknown concentration using redox titration data
• Electromotive Force (EMF) and Nernst Equation
  • Definition of electromotive force (EMF)
  • Nernst equation and its application to calculate cell potential
  • Relationship between cell potential and Gibbs free energy change
• Examples:
  • Determination of half-cell potentials and predicting redox reactions
  • Calculation of cell potential and Gibbs free energy change using Nernst equation

Slide 30

• Biochemical Reactions and Enzymes
  • Definition and types of biochemical reactions
  • Role of enzymes as biological catalysts
  • Enzyme-substrate complex and enzyme specificity
• Factors Affecting Biochemical Reactions
  • Effect of temperature and pH on enzymatic activity
  • Enzyme inhibitors and their impact on reaction rate
  • Use of enzyme kinetics to study biochemical reactions
• Examples:
  • Enzyme-catalyzed reactions in metabolism
  • Influence of temperature and pH on enzymatic activity