Reaction Rate Introduction

Chemical Reactions Reactants  Products Chemical Change Chemical Equation Reactants  Products

Reaction Rate What is reaction rate? How can we measure the rate of a reaction?

Collision Theory For a chemical reaction to occur: Reactants must collide Collision must have sufficient energy to cause a reaction Activation Energy Kinetic Energy of reactant particles ↔ Temperature Reactants must have correct orientation Discuss activation energy in terms of a match

Activation Energy and rate of reaction Larger Ea slows rate of reaction An activation barrier present for an exothermic reaction would explain the behavior of such reactions as H2 +O2 

What Factors Affect Reaction Rate? Brainstorm for variables Guide discussion on controlled and independent variables Focus on Temperature, mass reactants, volume water, state of tablet

Reaction for Lab 3NaHCO3(s) + H3C6H5O7(aq)  Sodium bicarbonate and citric acid sodium ions + citrate ions + water + carbon dioxide 3NaHCO3(s) + H3C6H5O7(aq)  3Na+(aq) + C6H5O7-3(aq) + 3H2O(l) + 3CO2(g)

How can we measure the rate of this reaction? 3NaHCO3(s) + H3C6H5O7(aq)  3Na+(aq) + C6H5O7-3(aq) + 3H2O(l) + 3CO2(g) Demo gas collection by water displacement

Total mass of container (g) Data Table Time (s) Total mass of container (g) Mass of CO2 (g)