Chemical Catalysis Overview

Chemical Catalysis

• Chemical catalysis is a process that increases the rate of a chemical reaction without being consumed in the reaction itself.
• Catalysts work by providing an alternative reaction pathway with a lower activation energy.
• Catalysts are unchanged at the end of the reaction.
• Temperature and pressure are other factors that affect reaction rate. However, catalysts are more efficient.

Contents

• Introduction to chemical catalysts
• Properties of catalysts
• Mechanisms of Catalysis
• Catalysts and reversible reactions
• Catalyst activity, selectivity, and autocatalysis
• Homogeneous Catalysis
• Acid-base catalysis (1-Specific Acid Catalysis, 2-Specific Base Catalysis, 3-Mechanism of Acid-Base Catalysis, 4-Examples of Acid-Base Catalysis)
• Enzyme Catalysis

Catalyst Types and Applications

• Catalysts can be classified based on their physical state (gas, liquid, solid).
• Catalysts can be classified based on the substances they are made from (inorganic or organic).
• Homogeneous catalysts are in the same phase as the reactants, while heterogeneous catalysts are in a different phase.
• Catalysts are crucial in various industries, including chemical manufacturing, automobiles, pharmaceuticals, and even the human body (enzymes).

Definition of Catalyst

• A catalyst is a substance that increases the rate of a chemical reaction without being consumed.
• Catalysts influence the reaction rate, not the equilibrium position.
• Catalysts provide an alternative reaction pathway with a lower activation energy.

Example Reactions with Catalysts

• Propane + Catalyst → Benzene + Catalyst
• Food + Enzymes → Small Molecules + Enzymes (e.g., proteins, fats, simple sugars)

Types of Catalysts & Catalytic Reactions

• Catalysts can be classified by their physical state (gas, liquid, or solid).
• Catalysts can be further classified by the substances they are made of (inorganic or organic).
• Classification of catalysts based on their method of action (e.g., homogeneous and heterogeneous catalysis).

Catalyst Classification

• Homogeneous catalysts: both catalyst and reactants share the same phase (e.g., gas or liquid).
• Heterogeneous catalysts: reactants and catalysts are in different phases (e.g., solid, gas, liquid).

Catalyst Action

• Mechanisms of catalysts' action (e.g., forming complexes with reactants/products).
• Impact of catalysts on reaction activation energy.
• How catalysts result in desired or undesired reactions at given conditions.

Catalyst Properties

• Catalysts are needed in small amounts.
• Catalysts generally show specificity to a certain reaction.
• Catalysts may undergo physical changes during the reaction process (like from crystalline to amorphous).
• Catalysts do not affect the equilibrium position of a reversible reaction.

Activation Energies

• Activation energy values of various reactions with and without catalysts (e.g. 2HI → H₂ + I₂ and 2NH₃ → N₂ + 3H₂)
• Reaction Rate equation for catalyzed and uncatalyzed reactions

Explore the fascinating world of chemical catalysis with this quiz. Learn about the properties, mechanisms, and types of catalysts, including homogeneous and enzyme catalysis. Test your understanding of how catalysts enhance reaction rates without being consumed.