vi Contents 3 STRUCTURE AND STEREOCHEMISTRY OF ALKANES 87 3-1 Classification of Hydrocarbons (Review)87 32 Molecular Formulas of Alkanes 88 Nomenclature of Alkanes 89 Summary:Rules for Naming Alkanes 94 3-4 Physical Properties of Alkanes 95 Uses and Sources of Alkanes 97 Reactions of Alkanes 99 Structure and Co Cgnormationsof ormations of Alkanes 100 Alkanes 106 3 8s107 2.12 nin Cy 3-13 ofyeoang 314 Conformations of Mono substituted Cyclohexanes 117 3-15 Conformations of Disubstituted Cvclohexanes 120 Problem-Solving Strategy:Recognizing Cis and Trans Isomers 122 3-16 Bicyclic Molecules 123 Essential lerms 125 Study Problems 129 4 THE STUDY OF CHEMICAL REACTIONS 132 4-1 Introduction 132 4-2 Chlorination of Methane 132 4-3 The Free-Radical Chain Reaction 134 Key Mechanism 4-1:Free-Radical Halogenation 136 4-4 Equilibrium Constants and Free Energy 138 Enthalpy and Entropy 140 4-6 Bond-Dissociation Enthalpies 142 Enthalpy Changes in Chlorination 143 Kinetics and the Rate Equation 145 4-9 Activation Energy and the Temperature Dependence of Rates 147 419 40 tep r epend logenation 150 414 tulate 157 4-15 61 4-16 162 Summary Reactive ms168 Study Proble ns170 3 STRUCTURE AND STEREOCHEMISTRY OF ALKANES 87 3-1 Classification of Hydrocarbons (Review) 87 3-2 Molecular Formulas of Alkanes 88 3-3 Nomenclature of Alkanes 89 Summary: Rules for Naming Alkanes 94 3-4 Physical Properties of Alkanes 95 3-5 Uses and Sources of Alkanes 97 3-6 Reactions of Alkanes 99 3-7 Structure and Conformations of Alkanes 100 3-8 Conformations of Butane 104 3-9 Conformations of Higher Alkanes 106 3-10 Cycloalkanes 107 3-11 Cis-trans Isomerism in Cycloalkanes 109 3-12 Stabilities of Cycloalkanes; Ring Strain 109 3-13 Cyclohexane Conformations 113 Problem-Solving Strategy: Drawing Chair Conformations 116 3-14 Conformations of Monosubstituted Cyclohexanes 117 3-15 Conformations of Disubstituted Cyclohexanes 120 Problem-Solving Strategy: Recognizing Cis and Trans Isomers 122 3-16 Bicyclic Molecules 123 Essential Terms 125 Study Problems 129 4 THE STUDY OF CHEMICAL REACTIONS 132 4-1 Introduction 132 4-2 Chlorination of Methane 132 4-3 The Free-Radical Chain Reaction 134 Key Mechanism 4-1: Free-Radical Halogenation 136 4-4 Equilibrium Constants and Free Energy 138 4-5 Enthalpy and Entropy 140 4-6 Bond-Dissociation Enthalpies 142 4-7 Enthalpy Changes in Chlorination 143 4-8 Kinetics and the Rate Equation 145 4-9 Activation Energy and the Temperature Dependence of Rates 147 4-10 Transition States 148 4-11 Rates of Multistep Reactions 149 4-12 Temperature Dependence of Halogenation 150 4-13 Selectivity in Halogenation 151 4-14 The Hammond Postulate 157 4-15 Radical Inhibitors 161 4-16 Reactive Intermediates 162 Summary: Reactive Intermediates 168 Essential Terms 168 Study Problems 170 vi Contents