Chapter 18.1 Rates of Reaction

Learning Objectives Understand what a reaction rates are a measure of Know the main tenets (points) of collision theory Be able to identify the factors that affect reaction rates Be able to interpret reaction diagrams

Chemical Kinetics  Chemical kinetics is the study of reactions rates  A reaction rate is the change in concentration of a reactant/product per unit time (Concentration is molarity)

Collision Theory Three conditions must be met … 1- Atoms/ions/molecules must collide 2- They must collide with enough energy 3- Must hit each other in a proper orientation

Collision Theory

collision theory orientation collision theory video game analogy

Factors Affecting Reaction Rates  Reaction rates are affected by: –Temperature –Concentration –Particle Size –Catalysts/Inhibitors

Factors Affecting Reaction Rates  Lets summarize: –Temperature (higher temperature makes rate faster) –Concentration (higher molarity makes rate faster) –Particle Size (smaller particles makes rate faster) –Catalysts/Inhibitors

Energy Diagram-Endothermic

Energy Diagram-Exothermic

Effect of Catalyst