Survival guide to general chemistry

Preface............................................................................................................................................xvii
Authors ............................................................................................................................................xix

Chapter 1 Unit Conversion and Density: An Introduction to Problem-Solving Methods ............1
I General Techniques for Performing Unit Conversions .....................................1
II General Procedures for Solving Density Problems ...........................................3
Process for Density Problems ............................................................................3
III General Examples for Density with Unit Conversions ......................................3
IV Practice Problems ..............................................................................................6
V Answers to Practice Problems ...........................................................................7

Chapter 2 Atomic Particles, Isotopes, and Ions: An Initial Look at Atomic Structure .............. 11
I General Concepts ............................................................................................ 11
II Atomic Symbols and Isotopes ......................................................................... 13
Isotopes: Atoms with the Same Value of Z But with a Different Value for A .....14
III Atomic Symbols and Ion Symbols .................................................................. 15
Additional Practice Examples ......................................................................... 16
IV Practice Problems ............................................................................................ 17
V Answers to Practice Problems ......................................................................... 17

Chapter 3 Working with Atomic Mass and Nuclear Mass ......................................................... 19
I General Concepts ............................................................................................ 19
II Potential Energy, Kinetic Energy, and Forces ................................................. 19
III Energy, Mass Loss, and the Strong Nuclear Force ..........................................20
IV Calculating Mass Using the Atomic Mass Unit ..............................................22
V Calculating the Approximate Mass of an Atom in amu, kg, or g ...................23
Process for Calculating Atomic Masses ..........................................................23
VI Average Atomic Mass for an Element .............................................................25
VII Practice Problems ............................................................................................26
VIII Answers to Practice Problems .........................................................................27

Chapter 4 Procedures for Writing Formulas and Naming Compounds ..................................... 31
I General Concepts ............................................................................................ 31
II Elemental Ions for Ionic Compounds .............................................................. 32
III Writing Formulas for Binary Ionic Compounds ............................................. 33
IV Naming Binary Ionic Compounds ..................................................................36
Procedure for Naming a Binary Ionic Compound ...........................................36
Additional Concepts ........................................................................................37
Additional Practice Examples .........................................................................38
V Writing Formulas for Ionic Compounds with Polyatomic Ions ......................39
Procedure for Writing Formulas for Ionic Compounds with
Polyatomic Ions ........................................................................................39
VI Naming Ionic Compounds with Polyatomic Ions ............................................40
Procedure for Naming Ionic Compounds Containing Polyatomic Ions .......... 41
VII Naming Binary Covalent Compounds ............................................................ 41
Covalent System for Naming Binary Covalent Compounds ........................... 42
VIII Additional Combination Practice Examples ................................................... 43
IX Practice Problems ............................................................................................46
X Answers to Practice Problems .........................................................................46

Chapter 5 An Introduction to Moles and Molar Mass ................................................................49
I General Concepts ............................................................................................49
Counting Numbers ...........................................................................................49
II Mass/Mole/Atom Conversions for Elements ................................................... 51
Procedure for Solving Mole Problems (Elements) .......................................... 51
III Mass/Mole/Molecule Conversions for Compounds ........................................ 53
Procedure for Solving Mole Problems (Compounds) .....................................54
IV Concepts for Using Ratios in Formulas ........................................................... 55
V Mass Percent of an Element in a Compound ...................................................58
VI Practice Problems ............................................................................................60
VII Answers to Practice Problems ......................................................................... 61

Chapter 6 Procedures for Calculating Empirical and Molecular Formulas ...............................69
I General Concept ..............................................................................................69
Concepts of Empirical or Molecular Formulas ...............................................69
II Procedure for Calculation of Simplest (Empirical) Formula of
Any Compound ...........................................................................................69
III Determination of the Simplest Formula from Element Mass Percent ............. 71
IV Determination of the True Molecular Formula for Molecules ........................72
Determining and Using the Multiple ...............................................................72
Procedure for Finding the Simplest Formula and True Molecular Formula........73
V Experimental Determination of Compound Formulas ....................................73
VI Practice Problems ............................................................................................ 76
VII Answers to Practice Problems .........................................................................77

Chapter 7 Writing Chemical Equations ......................................................................................83
I General Concepts ............................................................................................83
Conservation Laws ..........................................................................................83
II Writing Balanced Equations ............................................................................83
Process for Writing Balanced Equations from Descriptions ...........................84
III Practice Problems ............................................................................................86
IV Answers to Practice Problems .........................................................................86

Chapter 8 Techniques for Performing Stoichiometric Calculations ...........................................89
I General Concepts ............................................................................................89
II General Process for Stoichiometric Calculations Based on Balanced
Equations ....................................................................................................90
Diagram Form.................................................................................................. 91
Viewing Each Step ...........................................................................................92
III Percent Yield .....................................................................................................93
IV Limiting Reagent ..............................................................................................94
V Calculation of All Products and Reactants in a Limiting Reagent Problem ....96
VI Practice Problems ...........................................................................................100
VII Answers to Practice Problems ........................................................................ 102
Chapter 9 Precipitation and Acid/Base Aqueous Reactions: Concepts and Methods to
Design Complete Balanced Equations ..................................................................... 109
I General Concepts ............................................................................................ 109
II Solubility Equations and Aqueous Solution Formats ..................................... 109
Solution Formation Equations ........................................................................ 110
Formula Format .............................................................................................. 110
Ionic Format .................................................................................................... 111
Equation Formats for Complete Aqueous Solution Reactions ....................... 111
Formula Format Equation ............................................................................... 111
Total Ionic Format Equation ........................................................................... 111
Net Ionic Equation .......................................................................................... 112
III Precipitation Reactions ................................................................................... 113
Determining Ionic Compound Solubility ....................................................... 113
General Solubility Guideline Rules ................................................................ 114
Examples from the Previous Reactions .......................................................... 114
Predicting Products for Precipitation Reactions and Writing Equations ........ 114
Process for Completing and Writing Precipitation Reaction Equations ......... 114
IV Acid/Base Reactions: General Concepts ........................................................ 118
Properties of Acids .......................................................................................... 119
Properties of Bases..........................................................................................120
V Aqueous Acid/Base Reactions ........................................................................ 121
Acid Ionization Reaction and Acid Strength .................................................. 121
Aqueous Base Reactions ................................................................................. 122
Completing Acid/Base Reactions and Equations ........................................... 122
Examination of Reaction Requirements ......................................................... 123
A Specific Process for Completing and Writing Acid/Base
Reaction Equations ....................................................................................124
VI Practice Problems ........................................................................................... 127
VII Answers to Practice Problems ........................................................................ 128
Chapter 10 Oxidation Numbers: A First Look at Redox Reactions ........................................... 131
I General Concepts ............................................................................................ 131
II Oxidation Numbers ......................................................................................... 133
General Rules for Oxidation Numbers ........................................................... 133
III Process for the Analysis of Redox Reactions Using Oxidation Numbers ....... 135
IV Practice Problems ........................................................................................... 138
V Answers to Practice Problems ........................................................................ 138

Chapter 11 Solution Concentration, Molarity, and Solution Stoichiometry ............................... 141
I General Concepts ............................................................................................ 141
II Concentration Calculations Based on Molarity .............................................. 142
General Procedure for Solving Molarity Problems ........................................ 142
III Solution Stoichiometry .................................................................................. 145
Process for Solution Stoichiometry ............................................................... 145
IV Practice Problems .......................................................................................... 148
V Answers to Practice Problems ....................................................................... 149

Chapter 12 Light, Matter, and Spectroscopy .............................................................................. 153
I General Properties of Light ........................................................................... 153
Wave Properties ............................................................................................. 153
The Wave Nature of Light ............................................................................. 153
II Energy and the Quantum Theory of Light .................................................... 154
Energy and Light Calculations ...................................................................... 155
III Electrons and Atoms ..................................................................................... 156
IV Energy States, Light Interaction, and Electron Transitions ........................... 157
V Spectroscopy Calculations ............................................................................ 157
VI Spectra Calculations Using [E (Final Level) − E (Initial Level)] .................. 159
VII Practice Problems .......................................................................................... 161
VIII Answers to Practice Problems ....................................................................... 162

Chapter 13 Atomic Orbitals and the Electronic Structure of the Atom ..................................... 167
I Quantum Theory and Electron Orbitals ........................................................ 167
Orbital Architecture and Electron Spin ......................................................... 169
II Determining Electron Configurations of Elements ....................................... 170
Rules for Ground State Electron Configurations ........................................... 171
Closed Shells and the Noble Gas Electron Configuration ............................. 173
III Electron Configurations and Organization of the Periodic Table ................. 175
Process to Read the Electron Configuration Directly from the
Periodic Table ........................................................................................... 176
Valence Shell Electrons ................................................................................. 177
IV Ionization Energy and Electron Configuration Relationship ........................ 178
V Determination of Electron Configuration for Ions ........................................ 180
Electron Configuration for Negative Ions ...................................................... 180
Electron Configuration for Most Fixed-Charge Positive Ions ....................... 181
Ion Formation for Metals in Groups 4A and 5A ........................................... 182
Ion Formation for Transition Metals (B Groups) .......................................... 182
VI Practice Problems .......................................................................................... 183
VII Answers to Practice Problems ....................................................................... 183

Chapter 14 Alternate Methods for Visualizing and Constructing: Lewis Structures of
Covalent Molecules .................................................................................................. 185
I Introduction to Interpretation of Lewis Structures ........................................ 185
II Common Bonding Behavior for Non-Metals in Covalent Molecules ........... 186
General Concept of Normal Bonding in Covalent Molecules ....................... 186
Normal Neutral Bonding Rules ..................................................................... 187
Summary of Normal Neutral Bond Numbers for H, Be, B, C, N, O, F ........ 188
Summary of Normal Neutral Bond Numbers for Elements in Rows 3–5 ..... 190
III Constructing Lewis Structures for Covalent Molecules from H and the
Row-2 Elements: Bonding That Follows Normal Neutral Bonding Rules ..... 190
Lewis Structure Concepts ............................................................................... 190
Process for Molecules Containing H, Be, B, C, N, O, F ................................ 191
IV Constructing Lewis Structures for Covalent Molecules Using Elements
from Rows 3–5: Bonding Patterns That Follow Normal Neutral
Bonding Rules ............................................................................................ 195
V Constructing Molecules That Require Exceptions to Normal Neutral
Bonding Rules ............................................................................................ 198
Bonding Patterns through Exception Rules .................................................... 199
Exception Rule #1 .............................................................................200
Exception Rule #2 .............................................................................200
Exception Rule #3 .............................................................................200
Working with Exception Rule #1 ....................................................................200
Lewis Structures for Polyatomic Ions ............................................................. 201
Using Exception Rule #3 ................................................................................203
Other Uses for Exception Rules .....................................................................204
Resonance Structures ......................................................................................204
VI Practice Problems ...........................................................................................205
VII Answers to Practice Problems ........................................................................206

Chapter 15 Additional Techniques for Designing and Representing Structures of
Large Molecules .......................................................................................................209
I Techniques for Understanding and Designing Isomers of
Large Molecules .................................................................................209
General Rule #1 for the Number of Multiple Bonds (or Rings) .....................209
II Using Condensed Structural Formulas ........................................................... 213
Guidelines for Converting a Full Structure to a Condensed
Structural Formula ..................................................................................... 213
Guidelines for Expanding Condensed Formulas: Reconstructing the
Complete Molecule .................................................................................... 216
III Concept of Ring Structures and Line Drawings ............................................. 217
Structural Notation: Guidelines for Producing Line Drawings ...................... 218
Converting Line Drawings to Structural Formulas ......................................... 219
IV Practice Problems ........................................................................................... 219
V Answers to Practice Problems ........................................................................220

Chapter 16 Determining and Drawing Molecular Geometry and Polarity ................................223
I Concepts of Molecular Geometry...................................................................223
Types of Geometry Analysis for Central Atoms .............................................223
Counting Electron Regions .............................................................................223
Summary of E.R. Count ..................................................................................224
II Process for Complete Determination of Molecular Geometry and Polarity ..... 224
Descriptions of Geometric Figures for 2 to 4 Electron Regions .....................225
Descriptions of Geometric Figures for 5 and 6 Electron Regions ..................225
III Atom Geometry Determination from Electron Region Geometry ...............228
Additional Atom Geometries Derived from Trigonal Planar
and Tetrahedral .......................................................................................229
Additional Atom Geometries Derived from Trigonal Bipyramidal
and Octahedral ..........................................................................................230
IV Molecular Polarity ......................................................................................... 233
V Practice Problems ..........................................................................................238
VI Answers to Practice Problems .......................................................................238

Chapter 17 Summary Analysis of Central Atom Bonding, Hybridization, and Geometry ........243
I Concept of Sigma Bonds and Pi Bonds .........................................................243
II Concept of Hybridization ..............................................................................244
Electron Configuration and Hybridization of Carbon in CH4 .......................245
III Summary Tables ............................................................................................248
IV Practice Problems ..........................................................................................250
V Answers to Practice Problems ....................................................................... 251

Chapter 18 Concepts of Potential Energy, Enthalpy, and Bond Energy Calculations ................ 253
I Concept of Energy ......................................................................................... 253
II Chemical Bond Energetics ............................................................................254
Bond Strengths and Bond Dissociation Energy (BDE) ................................. 255
III Energy and Chemical Reactions ...................................................................256
Potential Energy Changes and Enthalpy .......................................................256
IV Potential Energy Diagrams ........................................................................... 257
Activation Energy ..........................................................................................258
V Calculating Reaction Enthalpy Values ..........................................................260
Process for Calculation of ΔH (Reaction) for a Balanced Equation ..............260
VI Reading an Energy Diagram .........................................................................264
VII Practice Problems ..........................................................................................265
VIII Answers to Practice Problems .......................................................................266
Chapter 19 Thermochemistry Calculations: Heat Capacity and Enthalpy .................................269
I General Concepts of Thermodynamics .........................................................269
The First Law of Thermodynamics ............................................................... 270
II Heat Capacity and Heat Transfer between Substances ................................. 271
Simple Heat Transfer for One Substance ...................................................... 273
Simple Heat Transfer between Two Substances ............................................ 274
III Energy and Enthalpy in Chemical Reactions ................................................ 278
IV Calorimetry ................................................................................................... 279
Determining ∆H and ∆E from Calorimetry ..................................................280
General Procedures for Solving Calorimetry Problems ................................280
V Enthalpy and Hess’s Law ...............................................................................284
Process for Applying Hess’s Law Calculations .............................................285
VI Calculation of ∆H (Reaction) from Enthalpies of Formation .......................287
VII Enthalpy and Stoichiometric Calculations .................................................... 291
VIII Practice Problems ..........................................................................................294
IX Answers to Practice Problems .......................................................................297
Chapter 20 Working with Gas Laws ...........................................................................................307
I Kinetic Theory of Gases ................................................................................307
Kinetic Energy, Temperature, and Graham’s Law for Diffusion ..................307
II The Ideal Gas Law ........................................................................................ 310
Measurements of Gas Pressure ...................................................................... 310
Solving Ideal Gas Law Problems .................................................................. 311
III Condition Changes for a Specific Gas Sample .............................................. 313
IV Solving Additional Problems Using Gas Laws ............................................. 315
Stoichiometric Calculations Using Gas Laws ............................................... 316
V Gas Mixtures and Law of Partial Pressures .................................................. 316
VI Practice Problems .......................................................................................... 319
VII Answers to Practice Problems .......................................................................320

Chapter 21 Guideline for Analyzing Intermolecular Forces and Calculating
Phase Change Enthalpies ......................................................................................... 325
I Overview of Interparticle and Intermolecular Forces ................................... 325
Phase Changes and Temperature ................................................................... 325
Descriptions of Interparticle Forces .............................................................. 326
II A Guideline for Comparing Total Strength of Intermolecular Forces
in Individual Compounds ......................................................................... 328
Strengths of Interparticle Forces ................................................................... 328
Process for Comparing Total Intermolecular Forces for Different
Compounds ............................................................................................... 328
III Enthalpy of Phase Changes ........................................................................... 333
IV Interparticle and Intermolecular Forces for Solutions................................... 336
Solubility Requirements ................................................................................ 336
Interparticle and Intermolecular Forces between Solutes and Solvents ........ 337
Process for Comparing Total Intermolecular Forces for Solutions ............... 337
V Enthalpies of Solutions .................................................................................. 339
VI Practice Problems ..........................................................................................340
VII Answers to Practice Problems ....................................................................... 341

Chapter 22 Kinetics Part 1: Rate Laws, Rate Equations, and an Introduction to Reaction
Mechanisms ..............................................................................................................345
I General Concept of Kinetics .........................................................................345
Additional Variables Affecting Reaction Rates ............................................345
Information Relationships for Kinetics and Mechanisms .............................346
II Introduction to Reaction Mechanisms ...........................................................346
III Description of Reactions by Mechanisms ..................................................... 347
Variability of Mechanisms ............................................................................ 347
IV Experimental Kinetics: Determining Reactant Orders and Rate
Constants from Integrated Rate Equations ...............................................348
Zero-Order Reactants ....................................................................................349
First-Order Reactants ....................................................................................349
Second-Order Reactants ................................................................................ 352
Experimental Determination of Reactant Orders in Multiple-
Concentration Rate Expressions ............................................................... 354
V Determining Rate Expressions from Initial Rate Data Calculations ............ 356
Relative Rate Measurements in the Balanced Equation ................................ 356
Working with Initial Rate Data Tables .......................................................... 357
Techniques for Solving for Reactant Orders by Comparing Data Sets ......... 357
Reactant Order Determination by Simple Inspection ................................... 358
Reactant Order Determination by Logarithmic Analysis .............................. 359
Determining the Complete Rate Expressions ............................................... 361
Determining the Value for the Rate Constant ............................................... 361
Determining the Value for Any Unknown Rate ............................................ 361
Determining Reactant Orders from Limited Data Sets ................................ 363
VI Practice Problems ..........................................................................................364
VII Answers to Practice Problems .......................................................................365

Chapter 23 General Techniques for Solving Equilibrium Problems .......................................... 371
I Concentration Quotient and Equilibrium Expression ................................... 371
Equilibrium Types and Expressions .............................................................. 372
II Techniques for Performing Equilibrium Calculations: Calculating K .......... 374
Process for Calculating the Numerical Value of the Equilibrium
Constant (K) from Concentrations ........................................................... 375
III Techniques for Performing Equilibrium Calculations ..................................380
Process for Calculating Equilibrium Concentrations of All
Reactants and Products from the Numerical Value of the
Equilibrium Constant (K) .........................................................................380
IV Techniques for Performing Equilibrium Calculations ..................................384
Using the Quadratic Formula ........................................................................384
V Techniques for Performing Equilibrium Calculations ..................................388
Using the Simplification Technique ..............................................................388
The Common Ion Effect ................................................................................390
VI Shifts in Equilibrium ..................................................................................... 391
VII Practice Problems .......................................................................................... 393
VIII Answers to Practice Problems ....................................................................... 395

Chapter 24 Kinetics Part 2: Application of Rate Laws and Rate Variables to Reaction
Mechanisms ..............................................................................................................407
I Predicting Rate Expressions from Mechanisms ............................................407
II General Concepts for Rate Expression Comparison: Identification of
the Rate Determining Step .......................................................................407
III Rules and Procedures for Predicting Rate Expressions ................................408
Rule 4 Procedure for Predicting Rate Expressions for Multi-Step
Reactions ...................................................................................................409
IV Determining Rate Expressions from Mechanism Descriptions ....................409
Notation for Mechanisms Written in Equation Form ....................................409
Comparison of Rate Expressions for Mechanisms #1, #2, #3 ....................... 411
V General Construction of Potential Energy Diagrams .................................... 414
VI Energy, Temperature, and Chemical Reactions ............................................ 416
Bonding Changes and Activation Energy ..................................................... 416
Bonding Changes and Temperature .............................................................. 416
Relationship between Rate Constant, Temperature, and Ea.......................... 417
VII Reading Potential Energy Diagrams ............................................................. 418
VIII Rates and Catalysis ........................................................................................ 422
IX Practice Problems .......................................................................................... 423
X Answers to Practice Problems .......................................................................426

Chapter 25 Thermodynamics: Entropy and Free Energy ........................................................... 433
I General Concepts of Entropy ........................................................................ 433
Predicting Entropy Changes for a Chemical Process .................................... 433
II Entropy and the Second Law of Thermodynamics ....................................... 436
III Calculation of Entropy and the Third Law of Thermodynamics .................. 438
IV Enthalpy, Entropy, and Chemical Spontaneity .............................................. 441
Enthalpy and Chemical Spontaneity .............................................................442
Entropy and Chemical Spontaneity ...............................................................442
Combining Enthalpy and Entropy as Spontaneity Measures ........................442
Spontaneity and Temperature ........................................................................443
V Reaction Spontaneity and Free Energy .........................................................445
Definition of Free Energy (ΔG) .....................................................................445
Enthalpy, Entropy, and Temperature Contributions to Free Energy .............446
Standard Free Energy (ΔG°) ..........................................................................447
Calculation of ΔG° at Variable Temperatures ............................................... 450
VI Non-Standard Free Energy (ΔG) and Concentrations ................................... 454
Calculating Non-Standard Free Energy (ΔGT) .............................................. 455
VII Non-Standard Free Energy (ΔG) and Equilibrium Constants ....................... 457
VIII Comprehensive Examples .............................................................................460
IX Practice Problems ..........................................................................................463
X Answers to Practice Problems .......................................................................465

Chapter 26 Acid/Base Equilibrium, pH, and Buffers ................................................................. 473
I Acid and Base Dissociation Reactions: Acid and Base Strength .................. 473
Autoionization of Water................................................................................. 476
II Relationship between Acid (pka) and Conjugate Base Strength .................... 476
III Process for Determining the Equilibrium Position for Acid/Base
Reactions ................................................................................................ 478
IV pH Calculations in Aqueous Solutions: General Concept of pH ................... 481
V pH Calculations in Aqueous Solutions: Reactions of One Acid or
Base with Water ........................................................................................482
VI pH Calculations in Aqueous Solutions: Solving General Acid/Base
Reactions .......................................................................................................488
VII The Common Ion Effect and Acid/Base Buffers ..........................................494
VIII The Hendersen–Hasselbach Equation ...........................................................496
IX Practice Problems ..........................................................................................497
X Answers to Practice Problems ....................................................................... 498
Index ......................................................................................................507