Ebook General, organic, and biological chemistry (5th edition) Part 1

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Ebook General, organic, and biological chemistry (5th edition) Part 1

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(BQ) Part 1 book General, organic, and biological chemistry has contents: Basic concepts about matter, measurements in chemistry, atomic structure and the periodic table, chemical bonding the covalent bond model, chemical calculations formula masses, moles, and chemical equations,...and other contents.

2880T_fm_i-xxviii.indd Page i 11/1/08 5:52:26 PM user-s131 /Volumes/MHSF/MH-SANFRAN/MHSF027/MHS General, Organic, and Biological Chemistry 2880T_fm_i-xxviii.indd Page ii 11/1/08 5:52:29 PM user-s131 /Volumes/MHSF/MH-SANFRAN/MHSF027/MHS 2880T_fm_i-xxviii.indd Page iii 11/1/08 5:52:30 PM user-s131 /Volumes/MHSF/MH-SANFRAN/MHSF027/MHS General, Organic, and Biological Chemistry F I F T H E D I T I O N H STEPHEN STOKER Weber State University Australia • Brazil • Japan • Korea • Mexico • Singapore • Spain • United Kingdom • United States 2880T_fm_i-xxviii.indd Page iv 11/5/08 1:06:52 AM user-s131 /Volumes/MHSF/MH-SANFRAN/MHSF027/MHS General, Organic, and Biological Chemistry, Fifth Edition H Stephen Stoker Acquisitions Editor: Kilean Kennedy Senior Development Editor: Rebecca Berardy Schwartz Associate Editor: Stephanie Van Camp © 2010 Brooks/Cole, Cengage Learning ALL RIGHTS RESERVED No part of this work covered by the copyright herein may be reproduced, transmitted, stored, or used in any 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Control Number: 2008934779 Art & Design Manager: Jill Haber Student Edition International Student Edition: 978-0-547-15281-3 ISBN-13: 978-0-495-83146-4 0-547-15281-7 ISBN-10: 0-495-83146-8 Manufacturing Coordinator: Miranda Klapper Text Designer: Nesbitt Graphics, Inc./Lisa Adamitis Art Editor: Jessyca Broekman Photo Researcher: Naomi Kornhauser Copy Editor: Peggy J Flanagan Illustrators: Laura Brown McEntee, Rossi Illustration & Design Cover Designer: Leonard Massiglia Cover Image: © Masterfile Royalty Free Compositor: Aptara, Inc Brooks/Cole 10 Davis Drive Belmont, CA 94002-3098 USA Cengage Learning is a leading provider of customized learning solutions with office locations around the globe, including Singapore, the United Kingdom, Australia, Mexico, Brazil, and Japan Locate your local office at www.cengage.com/global Cengage Learning products are represented in Canada by Nelson Education, Ltd For your course and learning solutions, visit www.cengage.com Purchase any of our products at your local college store or at our preferred online store www.ichapters.com Printed in the United States of America 12 11 10 09 08 2880T_fm_i-xxviii.indd Page v 11/2/08 10:55:08 AM user-s131 /Volumes/MHSF/MH-SANFRAN/MHSF027/MHS Brief Contents Preface PART I Chapter Chapter Chapter Chapter Chapter Chapter Chapter Chapter Chapter Chapter 10 Chapter 11 PART II Chapter 12 Chapter 13 Chapter 14 Chapter 15 Chapter 16 Chapter 17 PART III Chapter 18 Chapter 19 Chapter 20 Chapter 21 Chapter 22 Chapter 23 Chapter 24 Chapter 25 Chapter 26 xiv GENERAL CHEMISTRY Basic Concepts About Matter Measurements in Chemistry 22 Atomic Structure and the Periodic Table 51 Chemical Bonding: The Ionic Bond Model 83 Chemical Bonding: The Covalent Bond Model 108 Chemical Calculations: Formula Masses, Moles, and Chemical Equations 137 Gases, Liquids and Solids 163 Solutions 192 Chemical Reactions 223 Acids, Bases, and Salts 253 Nuclear Chemistry 292 ORGANIC CHEMISTRY Saturated Hydrocarbons 321 Unsaturated Hydrocarbons 361 Alcohols, Phenols, and Ethers 399 Aldehydes and Ketones 442 Carboxylic Acids, Esters, and Other Acid Derivatives Amines and Amides 514 473 BIOLOGICAL CHEMISTRY Carbohydrates 555 Lipids 608 Proteins 655 Enzymes and Vitamins 698 Nucleic Acids 734 Biochemical Energy Production Carbohydrate Metabolism 811 Lipid Metabolism 842 Protein Metabolism 875 Answers to Selected Exercises Photo Credits A-26 Index/Glossary A-27 777 A-1 v 2880T_fm_i-xxviii.indd Page vi 11/1/08 5:52:32 PM user-s131 /Volumes/MHSF/MH-SANFRAN/MHSF027/MHS 2880T_fm_i-xxviii.indd Page vii 11/1/08 5:52:32 PM user-s131 /Volumes/MHSF/MH-SANFRAN/MHSF027/MHS Contents Preface xiv PA RT I GE N E RAL C H E MI STRY Chapter Basic Concepts About Matter 1.1 Chemistry: The Study of Matter 1.2 Physical States of Matter 1.3 Properties of Matter 1.4 Changes in Matter CHEMISTRY AT A GLANCE Use of the Terms Physical and Chemical 1.5 Pure Substances and Mixtures 1.6 Elements and Compounds CHEMISTRY AT A GLANCE Classes of Matter 1.7 Discovery and Abundance of the Elements 1.8 Names and Chemical Symbols of the Elements 11 1.9 Atoms and Molecules 12 1.10 Chemical Formulas 15 CHEMICAL CONNECTIONS “Good” Versus “Bad” Properties for a Chemical Substance Elemental Composition of the Human Body 11 Chapter Measurements in Chemistry 22 2.1 2.2 2.3 2.4 Measurement Systems 22 Metric System Units 23 Exact and Inexact Numbers 26 Uncertainty in Measurement and Significant Figures 26 CHEMISTRY AT A GLANCE Significant Figures 28 2.5 Significant Figures and Mathematical Operations 28 2.6 Scientific Notation 32 2.7 Conversion Factors 34 2.8 Dimensional Analysis 36 CHEMISTRY AT A GLANCE Conversion Factors 38 2.9 Density 39 2.10 Temperature Scales 41 2.11 Heat Energy and Specific Heat 43 CHEMICAL CONNECTIONS Body Density and Percent Body Fat 40 Normal Human Body Temperature 44 Chapter Atomic Structure and the Periodic Table 51 3.1 Internal Structure of an Atom 51 3.2 Atomic Number and Mass Number 53 3.3 Isotopes and Atomic Masses 55 CHEMISTRY AT A GLANCE Atomic Structure 58 3.4 The Periodic Law and the Periodic Table 59 3.5 Metals and Nonmetals 62 3.6 Electron Arrangements Within Atoms 63 CHEMISTRY AT A GLANCE Shell–Subshell–Orbital 67 Interrelationships 3.7 Electron Configurations and Orbital Diagrams 67 3.8 The Electronic Basis for the Periodic Law and the Periodic Table 71 3.9 Classification of the Elements 73 CHEMISTRY AT A GLANCE Element Classification Schemes 75 and the Periodic Table CHEMICAL CONNECTIONS Protium, Deuterium, and Tritium: The Three Isotopes of Hydrogen 55 Metallic Elements and the Human Body 64 Iron: The Most Abundant Transition Element in the Human Body 74 Chapter Chemical Bonding: The Ionic Bond Model 83 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 Chemical Bonds 83 Valence Electrons and Lewis Symbols 84 The Octet Rule 86 The Ionic Bond Model 87 The Sign and Magnitude of Ionic Charge 89 Lewis Structures for Ionic Compounds 91 Chemical Formulas for Ionic Compounds 92 The Structure of Ionic Compounds 93 Recognizing and Naming Binary Ionic Compounds 94 CHEMISTRY AT A GLANCE Ionic Bonds and Ionic 95 Compounds 4.10 Polyatomic Ions 98 4.11 Chemical Formulas and Names for Ionic Compounds Containing Polyatomic Ions 100 CHEMISTRY AT A GLANCE Nomenclature of Ionic Compounds 102 CHEMICAL CONNECTIONS Fresh Water, Seawater, Hard Water, and Soft Water: A Matter of Ions 90 Tooth Enamel: A Combination of Monatomic and Polyatomic Ions 100 Chapter Chemical Bonding: The Covalent Bond Model 108 5.1 The Covalent Bond Model 108 5.2 Lewis Structures for Molecular Compounds 109 vii 2880T_fm_i-xxviii.indd Page viii 11/1/08 5:52:32 PM user-s131 /Volumes/MHSF/MH-SANFRAN/MHSF027/MHS 5.3 Single, Double, and Triple Covalent Bonds 111 5.4 Valence Electrons and Number of Covalent Bonds Formed 112 5.5 Coordinate Covalent Bonds 113 5.6 Systematic Procedures for Drawing Lewis Structures 114 5.7 Bonding in Compounds with Polyatomic Ions Present 117 5.8 Molecular Geometry 118 CHEMISTRY AT A GLANCE The Geometry 121 of Molecules 5.9 Electronegativity 121 5.10 Bond Polarity 124 5.11 Molecular Polarity 126 CHEMISTRY AT A GLANCE Covalent Bonds and Molecular 127 Compounds 5.12 Naming Binary Molecular Compounds 130 7.11 Vapor Pressure of Liquids 177 7.12 Boiling and Boiling Point 180 7.13 Intermolecular Forces in Liquids 181 CHEMISTRY AT A GLANCE Intermolecular Forces 185 CHEMICAL CONNECTIONS The Importance of Gas Densities 167 Blood Pressure and the Sodium Ion/Potassium Ion Ratio Hydrogen Bonding and the Density of Water 184 178 CHEMICAL CONNECTIONS Nitric Oxide: A Molecule Whose Bonding Does Not Follow “The Rules” 117 The Chemical Senses of Smell and Taste 122 Chapter Chemical Calculations: Formula Masses, Moles, and Chemical Equations 137 6.1 Formula Masses 137 6.2 The Mole: A Counting Unit for Chemists 138 6.3 The Mass of a Mole 140 6.4 Chemical Formulas and the Mole Concept 142 6.5 The Mole and Chemical Calculations 143 6.6 Writing and Balancing Chemical Equations 146 6.7 Chemical Equations and the Mole Concept 150 CHEMISTRY AT A GLANCE Relationships Involving the Mole 151 Concept 6.8 Chemical Calculations Using Chemical Equations 151 CHEMICAL CONNECTIONS Carbon Monoxide Air Pollution: A Case of Combining Ratios 153 Chemical Reactions on an Industrial Scale: Sulfuric Acid 156 Chapter Gases, Liquids, and Solids 7.1 7.2 7.3 7.4 7.5 The Kinetic Molecular Theory of Matter 163 Kinetic Molecular Theory and Physical States Gas Law Variables 167 Boyle’s Law: A Pressure-Volume Relationship Charles’s Law: A Temperature-Volume Relationship 170 7.6 The Combined Gas Law 172 7.7 The Ideal Gas Law 172 7.8 Dalton’s Law of Partial Pressures 173 CHEMISTRY AT A GLANCE The Gas Laws 175 7.9 Changes of State 176 7.10 Evaporation of Liquids 177 viii Contents 163 165 168 Chapter Solutions 192 8.1 Characteristics of Solutions 192 8.2 Solubility 193 8.3 Solution Formation 196 8.4 Solubility Rules 197 8.5 Solution Concentration Units 198 8.6 Dilution 205 CHEMISTRY AT A GLANCE Solutions 207 8.7 Colloidal Dispersions and Suspensions 208 8.8 Colligative Properties of Solutions 209 8.9 Osmosis and Osmotic Pressure 210 CHEMISTRY AT A GLANCE Summary of Colligative Property 215 Terminology 8.10 Dialysis 215 CHEMICAL CONNECTIONS Factors Affecting Gas Solubility 195 Solubility of Vitamins 199 Controlled-Release Drugs: Regulating Concentration, Rate, and Location of Release 206 The Artificial Kidney: A Hemodialysis Machine 216 Chapter Chemical Reactions 9.1 Types of Chemical Reactions 223 9.2 Redox and Nonredox Chemical Reactions CHEMISTRY AT A GLANCE Types of Chemical 228 Reactions 223 226 2880T_fm_i-xxviii.indd Page ix 11/1/08 5:52:34 PM user-s131 /Volumes/MHSF/MH-SANFRAN/MHSF027/MHS 9.3 Terminology Associated with Redox Processes 230 9.4 Collision Theory and Chemical Reactions 233 9.5 Exothermic and Endothermic Chemical Reactions 234 9.6 Factors That Influence Chemical Reaction Rates 235 9.7 Chemical Equilibrium 237 CHEMISTRY AT A GLANCE Factors That Increase Reaction 238 Rates 9.8 Equilibrium Constants 239 9.9 Altering Equilibrium Conditions: Le Châtelier’s Principle 243 CHEMICAL CONNECTIONS CHEMICAL CONNECTIONS Combustion Reactions, Carbon Dioxide, and Global Warming 227 “Undesirable” Oxidation–Reduction Processes: Metallic Corrosion 232 Stratospheric Ozone: An Equilibrium Situation 240 Chapter 10 Acids, Bases, and Salts Tobacco Radioactivity and the Uranium-238 Decay Series Preserving Food Through Food Irradiation 307 The Indoor Radon-222 Problem 309 Excessive Acidity Within the Stomach: Antacids and Acid Inhibitors 265 Acid Rain: Excess Acidity 272 Blood Plasma pH and Hydrolysis 274 Buffering Action in Human Blood 279 Electrolytes and Body Fluids 283 Chapter 11 Nuclear Chemistry 11.1 Stable and Unstable Nuclides 292 11.2 The Nature of Radioactive Emissions 292 293 303 253 10.1 Arrhenius Acid–Base Theory 253 10.2 Brønsted–Lowry Acid–Base Theory 254 10.3 Mono-, Di-, and Triprotic Acids 257 CHEMISTRY AT A GLANCE Acid–Base Definitions 258 10.4 Strengths of Acids and Bases 258 10.5 Ionization Constants for Acids and Bases 260 10.6 Salts 261 10.7 Acid–Base Neutralization Chemical Reactions 262 10.8 Self-Ionization of Water 263 10.9 The pH Concept 266 10.10 The pKa Method for Expressing Acid Strength 269 10.11 The pH of Aqueous Salt Solutions 270 CHEMISTRY AT A GLANCE Acids and Acidic 271 Solutions 10.12 Buffers 274 10.13 The Henderson–Hasselbalch Equation 277 CHEMISTRY AT A GLANCE Buffer Systems 278 10.14 Electrolytes 278 10.15 Equivalents and Milliequivalents of Electrolytes 280 10.16 Acid–Base Titrations 282 CHEMICAL CONNECTIONS 11.3 Equations for Radioactive Decay 295 11.4 Rate of Radioactive Decay 297 CHEMISTRY AT A GLANCE Radioactive Decay 299 11.5 Transmutation and Bombardment Reactions 300 11.6 Radioactive Decay Series 302 11.7 Chemical Effects of Radiation 302 11.8 Biochemical Effects of Radiation 305 11.9 Detection of Radiation 306 11.10 Sources of Radiation Exposure 307 11.11 Nuclear Medicine 309 11.12 Nuclear Fission and Nuclear Fusion 312 CHEMISTRY AT A GLANCE Characteristics of Nuclear 315 Reactions 11.13 Nuclear and Chemical Reactions Compared 316 PA RT II O RGA NI C CHE MIST RY Chapter 12 Saturated Hydrocarbons 321 12.1 Organic and Inorganic Compounds 321 12.2 Bonding Characteristics of the Carbon Atom 322 12.3 Hydrocarbons and Hydrocarbon Derivatives 322 12.4 Alkanes: Acyclic Saturated Hydrocarbons 323 12.5 Structural Formulas 324 12.6 Alkane Isomerism 326 12.7 Conformations of Alkanes 327 12.8 IUPAC Nomenclature for Alkanes 329 12.9 Line-Angle Structural Formulas for Alkanes 335 CHEMISTRY AT A GLANCE Structural Representations for 338 Alkane Molecules 12.10 Classification of Carbon Atoms 338 12.11 Branched-Chain Alkyl Groups 339 12.12 Cycloalkanes 340 12.13 IUPAC Nomenclature for Cycloalkanes 341 12.14 Isomerism in Cycloalkanes 342 12.15 Sources of Alkanes and Cycloalkanes 344 12.16 Physical Properties of Alkanes and Cycloalkanes 346 12.17 Chemical Properties of Alkanes and Cycloalkanes 347 CHEMISTRY AT A GLANCE Properties of Alkanes 349 and Cycloalkanes 12.18 Nomenclature and Properties of Halogenated Alkanes 350 CHEMICAL CONNECTIONS The Occurrence of Methane 325 The Physiological Effects of Alkanes 348 Chlorofluorocarbons and the Ozone Layer 351 Contents ix 458 Chapter 15 Aldehydes and Ketones 15.11 REACTION OF ALDEHYDES AND KETONES WITH ALCOHOLS Aldehydes and ketones react with alcohols to form hemiacetals and acetals Reaction with one molecule of alcohol produces a hemiacetal, which is then converted to an acetal by reaction with a second alcohol molecule B F Hemiacetal and acetal formation are very important biochemical reactions; they are crucial to understanding the chemistry of carbohydrates, which is considered in Chapter 18 Acid catalyst Aldehyde or ketone ϩ alcohol Hemiacetal ϩ alcohol Acid catalyst hemiacetal acetal The Greek prefix hemi- means “half.” When one alcohol molecule has reacted with the aldehyde or ketone, the compound is halfway to the final acetal Further information about these two reactions follows Hemiacetal Formation Hemiacetal formation is an addition reaction in which a molecule of alcohol adds to the carbonyl group of an aldehyde or ketone The H portion of the alcohol adds to the carbonyl oxygen atom, and the R—O portion of the alcohol adds to the carbonyl carbon atom ⌷O ⌯ A R1 O C O ⌷ O R2 A ⌯ ⌷ ⌯ B A C ϩ ⌷O R2 D G R1 ⌯ An aldehyde An alcohol A hemiacetal ⌷O ⌯ A R1 O C O ⌷ O R3 A R2 ⌷ ⌯ B A C ϩ ⌷O R3 D G R1 R2 A ketone Hemiacetals contain an alcohol group (hydroxyl group) and an ether group (alkoxy group) on the same carbon atom An alcohol A hemiacetal Formally defined, a hemiacetal is an organic compound in which a carbon atom is bonded to both a hydroxyl group (OOH) and an alkoxy group (OOR) The functional group for a hemiacetal is thus OH C OR The carbon atom of the hemiacetal functional group is often referred to as the hemiacetal carbon atom; it was the carbonyl carbon atom of the aldehyde or ketone that reacted A reaction mixture containing a hemiacetal is always in equilibrium with the alcohol and carbonyl compound from which it was made, and the equilibrium lies to the carbonyl compound side of the reaction (Section 9.9) hemiacetal Alcohol ϩ aldehyde 29 hemiacetal Alcohol ϩ ketone 29 This situation makes isolation of the hemiacetal difficult; in practice, it usually cannot be done An important exception to this difficulty with isolation is the case where the —OH and G CPO functional groups that react to form the hemiacetal come from the same molecule D This produces a cyclic hemiacetal rather than a noncyclic one, and cyclic acetals are more stable than the noncyclic ones and can be isolated 15.11 Reaction of Aldehydes and Ketones with Alcohols 459 Illustrative of intramolecular hemiacetal formation is the reaction H A 1C P O H A 2CH A A A 3CH 4CH 5CH Redrawing of the structure H2C so the two ends of the carbon chain are close to each other H2C O KO CH H CH2 O Ring closure CH2 H2C H2C EOH CH H CH2 CH2 Cyclic hemiacetal A OH Cyclic hemiacetals are very important compounds in carbohydrate chemistry, the topic of Chapter 18 EXAMPLE 15.4 Recognizing Hemiacetal Structures Indicate whether each of the following compounds is a hemiacetal a CH3 O CH O O O CH3 A OH b c d CH3 A CH3 O CH O CH O O O CH3 A OH OH A CH3 O C O CH3 A O O CH3 O OH Solution In each part, we will be looking for the following structural feature: the presence of an —OH group and an —OR group attached to the same carbon atom a We have an —OH group and an —OR group attached to the same carbon atom The compound is a hemiacetal b We have an —OH group and an —OR group attached to the same carbon atom The compound is a hemiacetal c The —OH and —OR groups present in this molecule are attached to different carbon atoms Therefore, the molecule is not a hemiacetal d We have a ring carbon atom bonded to two oxygen atoms: one oxygen atom in an —OH substituent and the other oxygen atom bonded to the rest of the ring (the same as an R group) This is a hemiacetal Practice Exercise 15.4 Indicate whether each of the following compounds is a hemiacetal a OH A CH2 A OOCH3 b c d CH3 A CH3 OOOCH A HOOCH A CH3 Answers: a Yes; b Yes; c No; d Yes CH3 A CH2 A CH3OOOC OOH A CH3 O OH CH3 460 B F Chapter 15 Aldehydes and Ketones Acetal Formation This is our second encounter with condensation reactions The first encounter involved intermolecular alcohol dehydration (Section 14.9) If a small amount of acid catalyst is added to a hemiacetal reaction mixture, the hemiacetal reacts with a second alcohol molecule, in a condensation reaction, to form an acetal OH A R1OCOOR2 ϩ R3OOH A H A hemiacetal Acetals have two alkoxy groups (—OR) attached to the same carbon atom Hϩ OR3 A R1O COOR2 ϩ HOOH A H An alcohol An acetal An acetal is an organic compound in which a carbon atom is bonded to two alkoxy groups (—OR) The functional group for an acetal is thus OR C OR A specific example of acetal formation from a hemiacetal is OH A CH3O CH ϩ CH3 O CH2OOH A OO CH3 Hϩ OO CH2O CH3 A CH3O CH ϩ HOOH A OO CH3 Note that acetal formation does not involve addition to a carbon–oxygen double bond as hemiacetal formation does; no double bond is present in either of the reactants involved in acetal formation Acetal formation involves a substitution reaction; the —OR group of the alcohol replaces the —OH group on the hemiacetal Figure 15.10 shows molecular models for acetaldehyde (the two-carbon aldehyde) and the hemiacetal and acetal formed when this aldehyde reacts with ethyl alcohol B Acetal Hydrolysis F In Section 24.1, we will find that the enzyme-catalyzed hydrolysis of acetals is an important step in the digestion of carbohydrates Acetals, unlike hemiacetals, are easily isolated from reaction mixtures They are stable in basic solution but undergo hydrolysis in acidic solution A hydrolysis reaction is the reaction of a compound with H2O, in which the compound splits into two or more fragments as the elements of water (H— and —OH) are added to the compound The products of acetal hydrolysis are the aldehyde or ketone and alcohols that originally reacted to form the acetal O R1 C O R2 ϩ H Acid catalyst OH Acetal O ϩ R1 C OH ϩ R2 Aldehyde or ketone Figure 15.10 Molecular models for acetaldehyde and its hemiacetal and acetal formed by reaction with ethyl alcohol Acetaldehyde Acetaldehyde hemiacetal with ethyl alcohol Acetaldehyde acetal with ethyl alcohol O H 15.11 Reaction of Aldehydes and Ketones with Alcohols 461 For example, CH3 O CH2 C O CH3 ϩH CH3 OH O Acid catalyst CH3 C CH3 ϩ CH3 OH ϩ CH3 CH2 OH CH3 The carbonyl hydrolysis product is an aldehyde if the acetal carbon atom has a hydrogen atom attached directly to it, and it is a ketone if no hydrogen attachment is present In the preceding example, the carbonyl product is a ketone because the two additional acetal carbon atom attachments are methyl groups EXAMPLE 15.5 Predicting Products in Acetal Hydrolysis Reactions Draw the structures of the aldehyde (or ketone) and the two alcohols produced when the following acetals undergo hydrolysis in acidic solution a OOCH3 A CH3O CH2OCH A OOCH2O CH3 b CH3 A CH3OC OOO CHOCH3 A A CH3 O A CH3OC O CH3 A CH3 Solution a Each of the alkoxy (—OR) groups present will be converted into an alcohol during the hydrolysis Because the acetal carbon atom has a H attachment, the remainder of the molecule becomes an aldehyde, with the carbon atom to which the alkoxy groups were attached becoming the carbonyl carbon atom OO CH3 A CH3OCH2O CH A OO CH2OCH3 CH3 OOH An alcohol O B CH3 OCH2 O COH CH3 OCH2 OOH An aldehyde An alcohol b Again, each of the alkoxy groups present will be converted into an alcohol during the hydrolysis Because the acetal carbon atoms lacks a H attachment, the remainder of the molecule becomes a ketone O B CH3 A CH 3O C OO O CH O CH A A O CH A CH 3O C OCH A CH3 CH 3O C OCH A ketone CH 3OCH OOH An alcohol A CH CH A CH 3OC OOH A An alcohol CH Practice Exercise 15.5 Draw the structures of the aldehyde (or ketone) and the two alcohols produced when the following acetal undergoes hydrolysis in acidic solution (continued) 462 Chapter 15 Aldehydes and Ketones CH3 A CH3O CH2 O CH2 OOO COOO CH2 OCH3 A CH3 Answers: CH3 O CH2 OCH2 O OH (alcohol), CH3 O CH2OOH (alcohol), O B CH3 O C O CH3 (ketone), Nomenclature for Hemiacetals and Acetals A “descriptive” type of common nomenclature that includes the terms hemiacetal and acetal as well as the name of the carbonyl compound (aldehyde or ketone) produced in the hydrolysis of the hemiacetal or acetal is commonly used in describing such compounds Two examples of such nomenclature are OH C C C O C C H Methyl hemiacetal of propanal O C C C O C C C Diethyl acetal of propanone The Chemistry at a Glance feature below summarizes reactions that involve aldehydes and ketones Summary of Chemical Reactions Involving Aldehydes and Ketones CHEMICAL REACTIONS OF ALDEHYDES AND KETONES Oxidation O2 in air is oxidizing agent Aldehyde Ketone Reduction Hemiacetal and Acetal Formation carboxylic acid no reaction Reaction with one alcohol molecule produces a hemiacetal Reaction with two alcohol molecules produces an acetal Aldehyde Ketone hemiacetal hemiacetal acetal acetal H2 gas is reducing agent Ni, Pt, or Cu is catalyst Aldehyde Ketone PREPARATION OF ALDEHYDES AND KETONES Alcohol Oxidation KMnO4 and K2Cr2O7 are common oxidizing agents 1° alcohol 2° alcohol aldehyde ketone 1° alcohol 2° alcohol 463 15.12 Formaldehyde-Based Polymers Figure 15.11 When a mixture of phenol and formaldehyde dissolved in acetic acid is treated with concentrated hydrochloric acid, a cross-linked phenol–formaldehyde network polymer is formed 15.12 FORMALDEHYDE-BASED POLYMERS Many types of organic compounds can serve as reactants (monomers) for polymerization reactions, including ethylenes (Section 13.10), alcohols (Section 14.10), and carbonyl compounds Formaldehyde, the simplest aldehyde, is a prolific “polymer former.” As representative of its polymer reactions, let us consider the reaction between formaldehyde and phenol, under acidic conditions, to form a phenol–formaldehyde network polymer (see Figure 15.11) A network polymer is a polymer in which monomers are connected in a three-dimensional cross-linked network When excess formaldehyde is present, the polymerization proceeds via mono-, di-, and trisubstituted phenols that are formed as intermediates in the reaction between phenol and formaldehyde OH OH O B Acidic ϩ n HOCOH conditions OH CH2OH HOCH2 OH CH2OH and HOCH2 CH2OH and CH2OH The substituted phenols then interact with each other by splitting out water molecules The final product is a complex, large, three-dimensional network polymer in which monomer units are linked via methylene (—CH2—) bridges OH CH2 CH2 CH2 HO HO CH2 CH2 CH2 CH2 Figure 15.12 Bakelite jewelry in use during the 1930–1950 time period CH2 CH2 OH HO CH2 CH2 The first synthetic plastic, Bakelite, produced in 1907, was a phenol–formaldehyde polymer Early uses of Bakelite were in the manufacture of billiard balls and “plastic” jewelry (Figure 15.12) Modern phenol–formaldehyde polymers, called phenolics, are adhesives used in the production of plywood and particle board 464 Chapter 15 Aldehydes and Ketones 15.13 SULFUR-CONTAINING CARBONYL GROUPS The introduction of sulfur into a carbonyl group produces two different classes of compounds depending on whether the sulfur atom replaces the carbonyl oxygen atom or the carbonyl carbon atom Replacement of the carbonyl oxygen atom with sulfur produces thiocarbonyl compounds— thioaldehydes (thials) and thioketones (thiones)—the simplest of which are S C H S H C CH3 Thioformaldehyde (Methanethial) CH3 Thioacetone (Propanethione) Thiocarbonyl compounds such as these are unstable and readily decompose Replacement of the carbonyl carbon atom with sulfur produces sulfoxides, compounds that are much more stable than thiocarbonyl compounds The oxidation of a thioether (sulfide) [Section 14.21] constitutes the most common route to a sulfoxide O R S R [O] S R Thioether R Sulfoxide A highly interesting sulfoxide is DMSO (dimethyl sulfoxide), a sulfur analog of acetone, the simplest ketone O S CH3 O CH3 CH3 DMSO C CH3 Acetone DMSO is an odorless liquid with unusual properties Because of the presence of the polar sulfur–oxide bond, DMSO is miscible with water and also quite soluble in less polar organic solvents When rubbed on the skin, DMSO has remarkable penetrating power and is quickly absorbed into the body, where it relieves pain and inflammation For many years it has been heralded as a “miracle drug” for arthritis, sprains, burns, herpes, infections, and high blood pressure However, the FDA has steadfastly refused to approve it for general medical use For example, the FDA says that DMSO’s powerful penetrating action could cause an insecticide on a gardener’s skin to be carried accidentally into his or her bloodstream Another complication is that DMSO is reduced in the body to dimethyl sulfide, a compound with a strong garlic-like odor that soon appears on the breath O CH3 S CH3 Reduction CH3 S CH3 The FDA has approved DMSO for use in certain bladder conditions and as a veterinary drug for topical use in nonbreeding dogs and horses For example, DMSO is used as an anti-inflammatory rub for race horses c O N C E P TS TO R E M E M B E R The carbonyl group A carbonyl group consists of a carbon atom bonded to an oxygen atom through a double bond Aldehydes and ketones are compounds that contain a carbonyl functional group The carbonyl carbon in an aldehyde has at least one hydrogen attached to it, and the carbonyl carbon in a ketone has no hydrogens attached to it (Sections 15.1 through 15.3) Nomenclature of aldehydes and ketones The IUPAC names of aldehydes and ketones are based on the longest carbon chain that contains the carbonyl group The chain numbering is done from the end that results in the lowest number for the carbonyl group The names of aldehydes end in -al, those of ketones in -one (Sections 15.4 and 15.5) Exercises and Problems Isomerism for aldehydes and ketones Constitutional isomerism is possible for aldehydes and for ketones when four or more carbon atoms are present Aldehydes and ketones with the same number of carbon atoms and the same degree of saturation have the same molecular formula and thus are functional group isomers of each other (Section 15.6) Physical properties of aldehydes and ketones The boiling points of aldehydes and ketones are intermediate between those of alcohols and alkanes The polarity of the carbonyl groups enables aldehyde and ketone molecules to interact with each other through dipole–dipole interactions They cannot, however, hydrogen-bond to each other Lower-molecular-mass aldehydes and ketones are soluble in water (Section 15.8) k 465 Preparation of aldehydes and ketones Oxidation of primary and secondary alcohols, using mild oxidizing agents, produces aldehydes and ketones, respectively (Section 15.9) Oxidation and reduction of aldehydes and ketones Aldehydes are easily oxidized to carboxylic acids; ketones not readily undergo oxidation Reduction of aldehydes and ketones produces primary and secondary alcohols, respectively (Section 15.10) Hemiacetals and acetals A characteristic reaction of aldehydes and ketones is the addition of an alcohol across the carbonyl double bond to produce hemiacetals The reaction of a second alcohol molecule with a hemiacetal produces an acetal (Section 15.11) EY R E A C T I O N S A N D E Q U AT I O N S Oxidation of an aldehyde to give a carboxylic acid (Section 15.10) O B R OC OH [O] O B R OC OOH Attempted oxidation of a ketone (Section 15.10) O B ROCO RЈ [O] no reaction Reduction of an aldehyde to give a primary alcohol (Section 15.10) O B ROCOH ϩ H2 Catalyst OH A R OC OH A H Reduction of a ketone to give a secondary alcohol (Section 15.10) O B ROCO RЈ ϩ H2 Catalyst OH A R OC ORЈ A H Addition of an alcohol to an aldehyde to form a hemiacetal and then an acetal (Section 15.11) O B R1OC OH ϩ R2 OOOH Hϩ Aldehyde OH A R1OCOOR2 A H Hemiacetal OH A R1OC OOR2 ϩ R3 OOH A H Hϩ Hemiacetal OR3 A R1OC OOR2 ϩ H2O A H Acetal Hydrolysis of an acetal to yield an aldehyde and two alcohols (Section 15.11) OR3 A R1OCOOR2 ϩ H2O A H Hϩ O B R1OCOH ϩ R2 OOH ϩ R3 OOH EXERCISES an d PR O BL EMS The members of each pair of problems in this section test similar material The Carbonyl Group (Section 15.1) 15.1 Indicate which of the following compounds contain a carbonyl group a b CH3OOOCH3 O B CH3OCH2O CH2OC OH CH3 O c d A B OP COH CH3O C OCH2O CH3 15.2 Indicate which of the following compounds contain a carbonyl group a O B CH3O CH2OC OCH2 O CH3 b CH3O CH2OOOCH2 O CH3 c O B CH3OCH2O COH d CH3 A CH3OCH2O CPO 466 Chapter 15 Aldehydes and Ketones 15.3 What are the similarities and differences between the bonding in a carbon–oxygen double bond and that in a carbon–carbon double bond? 15.4 Use dϩ and dϪ notation to show the polarity in a carbon–oxygen double bond 15.5 What are the approximate bond angles between the atoms attached to the carbonyl carbon atom of a carbonyl group? 15.6 What is the geometrical arrangement for the atoms directly attached to the carbonyl carbon atom in a carbonyl compound? Compounds Containing a Carbonyl Group (Section 15.2) 15.7 Indicate whether each of the following types of compounds contain a carbonyl group a Aldehyde b Ester c Alcohol d Carboxylic acid 15.8 What elements are present in each of the following types of hydrocarbon derivatives? a Carboxylic acid b Amide c Aldehyde d Ketone 15.13 Draw the structures of the two simplest aldehydes and the two simplest ketones 15.14 One- and two-carbon ketones not exist Explain why 15.15 Classify each of the following structures as an aldehyde, a ketone, or neither a O B C OH c O b O B COOO CH3 d O B CO CH3 15.16 Classify each of the following structures as an aldehyde, a ketone, or neither a O B CO CH2O CH3 b O B COOH c O B C OH d O 15.9 Identify the type of hydrocarbon derivative associated with each of the following functional group designations a O O b R c C O R H d C O R R C NH2 R C OH 15.10 Write the structural formula for the simplest member of each of the following types of hydrocarbon derivatives a Aldehyde b Ester c Ketone d Carboxylic acid The Aldehyde and Ketone Functional Groups (Section 15.3) 15.11 Classify each of the following structures as an aldehyde, a ketone, or neither a O B CH3O CH2O CH2O COOH O B CH3O CO CH3 c CH3O O O CH2OCH3 b d CH3 OCHO 15.12 Classify each of the following structures as an aldehyde, a ketone, or neither a O B CH3 OC O CH2 OCH3 O b B CH3O CH2OCH2OCO O O CH3 c O B CH3O CH2OCHOCOH A CH3 d CH3 A CH3 OCOCH2 OCHO A CH3 O Nomenclature for Aldehydes (Section 15.4) 15.17 Assign an IUPAC name to each of the following aldehydes a O B CH3O CH2O CHOC OH A CH3 b O B CH3O CHOCH2 OCH2 OC OH A CH2O CH2O CH3 c O B CH2O CH2OCOH d CH3O CH2O CHO 15.18 Assign an IUPAC name to each of the following aldehydes a O B CH3O CHOCH2 OCH2 OC OH A CH3 O b B CH3O CH2O CHOC OH A CH2 A CH3 O c B CH2OCOH d CH3 OCH2 OCH2 OCHO Exercises and Problems 15.19 Assign an IUPAC name to each of the following aldehydes a b O B O B H c H d O B O B H H 15.20 Assign an IUPAC name to each of the following aldehydes a b O B H O B c O B O B H H 15.21 Draw a structural formula for each of the following aldehydes a 3-Methylpentanal b 2-Ethylhexanal c 2,2-Dichloropropanal d 4-Hydroxy-2-methyloctanal 15.22 Draw a structural formula for each of the following aldehydes a 2-Methylpentanal b 4-Ethylhexanal c 3,3-Dimethylhexanal d 2,3-Dibromopropanal 15.23 Draw a structural formula for each of the following aldehydes a Formaldehyde b Propionaldehyde c 2-Chlorobenzaldehyde d 2,4-Dimethylbenzaldehyde 15.24 Draw a structural formula for each of the following aldehydes a Acetaldehyde b Butyraldehyde c Dichloroacetaldehyde d 2-Methylbenzaldehyde 15.25 Assign a common name to each of the following aldehydes a c a O B CH3O CH2OCO CH3 O b B CH3 OCHO CHO CO CHO CH3 A A A CH3 CH3 CH3 c O B CH3OCHO CH2O CH2O CO CH2O CH3 A CH3 O B CH3 OCH2 OCOCHO Cl A Cl 15.28 Using IUPAC nomenclature, name each of the following ketones O a B CH3O CO CH2OCH2O CH2O CH3 d H d 467 O B CH3 OCH2 OCOH b CH3O CH2OCHO O B Cl OCHO COH A Cl d O B CH3O CH2O COCH2 OCHO CH3 A CH2 A CH3 O c B CH3 OCHO CO CHO CH3 A A Cl Br d O B CH3O CHO CO CH2OCH2 A A Cl Cl b 15.29 Assign an IUPAC name to each of the following ketones a O B C OH c b O B O B d O B O B Cl 15.26 Assign a common name to each of the following aldehydes a c b CH3O CH2 OC CH2 OCHO Cl O A B Cl O C OC OH A Cl O B C OH d 15.30 Assign an IUPAC name to each of the following ketones a O B CH3 OCH2 OCH2 OC OH b O B c O B O B d B O 15.31 Using IUPAC nomenclature, name each of the following ketones a b O d CH3 O O Br c O Nomenclature for Ketones (Section 15.5) 15.27 Using IUPAC nomenclature, name each of the following ketones CH3 Cl 468 Chapter 15 Aldehydes and Ketones 15.32 Using IUPAC nomenclature, name each of the following ketones a O O b 15.51 How many hydrogen bonds can form between an acetone molecule and water molecules? 15.52 How many hydrogen bonds can form between an acetaldehyde molecule and water molecules? CH3 c O CH3 d O Br 15.33 Draw a structural formula for each of the following ketones a 3-Methyl-2-pentanone b 3-Hexanone c Cyclobutanone d Chloropropanone 15.34 Draw a structural formula for each of the following ketones a 2-Methyl-3-pentanone b 2-Pentanone c Bromopropanone d Cyclopentanone 15.35 Draw a structural formula for each of the following ketones a Isopropyl propyl ketone b Chloromethyl methyl ketone c Acetophenone d Methyl phenyl ketone 15.36 Draw a structural formula for each of the following ketones a Methyl tert-butyl ketone b Dichloromethyl ethyl ketone c Benzophenone d Diphenyl ketone Isomerism for Aldehydes and Ketones (Section 15.6) 15.37 Give IUPAC names for all saturated unbranched-chain com- pounds that are named as the following a Heptanals b Heptanones 15.38 Give IUPAC names for all saturated unbranched-chain compounds that are named as the following a Hexanals b Hexanones 15.39 How many aldehydes and how many ketones exist with each of the following molecular formulas? b C3H6O a CH2O 15.40 How many aldehydes and how many ketones exist with each of the following molecular formulas? b C4H8O a C2H4O 15.41 For which values of x is the ketone name x-methyl-3-hexanone a correct IUPAC name? 15.42 For which values of x is the ketone name x-methyl-3-pentanone a correct IUPAC name? 15.43 Draw skeletal structural formulas for the four aldehydes and three ketones that have the molecular formula C5H10O 15.44 Draw skeletal structural formulas for the eight aldehydes and six ketones that have the molecular formula C6H12O Selected Common Aldehydes and Ketones (Section 15.7) 15.45 What is the difference between the substances formaldehyde and formalin? 15.46 What is the odor associated with and what are the uses for the substance formalin? 15.47 What are the general properties of and uses for the substance acetone? 15.48 What is the significance of the odor of acetone on the breath of a person? Physical Properties of Aldehydes and Ketones (Section 15.8) 15.49 Aldehydes and ketones have higher boiling points than alkanes of similar molecular mass Explain why 15.50 Aldehydes and ketones have lower boiling points than alcohols of similar molecular mass Explain why 15.53 Would you expect ethanal or octanal to be more soluble in water? Explain your answer 15.54 Would you expect ethanal or octanal to have the more fragrant odor? Explain your answer Preparation of Aldehydes and Ketones (Section 15.9) 15.55 Draw the structure of the aldehyde or ketone formed from oxi- dation of each of the following alcohols Assume that reaction conditions are sufficiently mild that any aldehydes produced are not oxidized further to carboxylic acids a CH3O CH2OCH2 OCH2 OCH2 OOH b CH3O CH2OCHOOH A CH3 c CH3 A CH3O CO CH2OCH2OOH A CH3 d CH3 OH 15.56 Draw the structure of the aldehyde or ketone formed from oxi- dation of each of the following alcohols Assume that reaction conditions are sufficiently mild that any aldehydes formed are not oxidized further to carboxylic acids a CH3O CH2OCHOCH2 OOH A CH3 b CH3 OCHO CHOOH A A CH3 CH3 CH3 c A CH3O COOH A CH3 d CH2OCH3 OH 15.57 Draw the structure of the alcohol needed to prepare each of the following aldehydes or ketones by alcohol oxidation a Diethyl ketone b Phenylpropanone c Acetaldehyde d 2-Ethylhexanal 15.58 Draw the structure of the alcohol needed to prepare each of the following aldehydes or ketones by alcohol oxidation a Propanal b Dipropyl ketone c 3-Phenyl-2-butanone d Cyclohexanone Oxidation and Reduction of Aldehydes and Ketones (Section 15.10) 15.59 Draw the structural formula of the organic product when each of the following aldehydes is oxidized to a carboxylic acid a Ethanal b Pentanal c Formaldehyde d 3,4-Dichlorohexanal 469 Exercises and Problems 15.60 Draw the structural formula of the organic product when each of the following aldehydes is oxidized to a carboxylic acid a Butanal b 2-Methylpentanal c Acetaldehyde d Benzaldehyde 15.61 What are the characteristics of a positive Tollens test for aldehydes? 15.62 What are the characteristics of a positive Benedict’s test for aldehydes? 15.63 What is the oxidizing agent in Benedict’s solution? 15.64 What is the oxidizing agent in Tollens solution? 15.65 Which of the following compounds would react with Tollens solution? a c CH3 O A B CH3 OCOCH2 OCH2 OC OH A CH3 d O B CH3OCH2O C O CH3 Hemiacetal Formation (Section 15.11) 15.69 When an alcohol molecule (R—O—H) adds across a carbon– oxygen double bond, into what “fragments” is the alcohol split? 15.70 When an alcohol molecule (R—O—H) adds across a carbon– oxygen double bond, which part of the alcohol molecule adds to the carbonyl oxygen atom? O B CH3O CH2O CH2O CO CH3 b O B CH3 OCH2 OCH2 OC OH O O c d B B CH3OCHOCH2 OC OH CH3OCHO CO CH3 A A OH OH 15.71 Indicate whether each of the following compounds is a hemiacetal 15.66 Which of the following compounds would react with Benedict’s 15.72 Indicate whether each of the following compounds is a hemiacetal solution? a O b O B B CH3 OCH2 OCOH CH3O CO CH3 O c B CH3O CH2O CHO CO CH2O CH3 A OH d O B CH3O CHOCHO CH2O C OH A A CH3 CH3 15.67 Draw the structure of the major organic compound produced when each of the following compounds is reduced using molecular H2 and a Ni catalyst O a B CH3 OCH2 OCH2 OC OH O b B CH3OCH2O CO CH2O CH3 CH3 O c A B CH3OCHOCH2 OC OH CH3 O d A B CH3OCHO CO CH2O CH2O CH3 15.68 Draw the structure of the major organic compound produced when each of the following compounds is reduced using molecular H2 and a Ni catalyst a O B CH3OCH2O CH2O CO CH3 b O B CH3 OCH2 OCH2 OCH2 OC OH a CH3O CH2OOOCH3 b OH A CH3 OC OCH3 A OOCH3 c O d OH a c OH A CH3O CH2O CO CH3 A OH O O OO CH3 b OH A CH3O CH2O CO CH3 A OOCH3 d OH OOCH3 OH 15.73 Draw the structural formula of the hemiacetal formed from each of the following pairs of reactants a Acetaldehyde and ethyl alcohol b 2-Pentanone and methanol c Butanal and ethanol d Acetone and isopropyl alcohol 15.74 Draw the structural formula of the hemiacetal formed from each of the following pairs of reactants a Acetaldehyde and methanol b 2-Pentanone and ethyl alcohol c Butanal and isopropyl alcohol d Acetone and ethanol 15.75 Draw the structural formula of the missing compound in each of the following reactions a O B CH3 O (CH2)2 O C OH ϩ CH3O CH2OOH b OH A Hϩ ? ϩ CH3OOH CH3OCH2 O CH A OO CH3 c O B Hϩ CH3 OCH2 O C OCH3 ϩ CH3OOH ? d CH2OH OOH O Hϩ J ? C G OH H Hϩ ? 470 Chapter 15 Aldehydes and Ketones 15.76 Draw the structural formula of the missing compound in each a of the following reactions a O B CH3O CH2 OC OH ϩ CH3OOH b ? ϩ CH3OCH2 OOH Hϩ Hϩ ? OH A CH3OCH2 O CH A OO CH2 OCH3 O B CH3OCH2 OCH2 O C OCH3 ϩ CH3OCH2 OOH CH2OH d OOH O Hϩ J C ? HO G H c Hϩ ? Acetal Formation (Section 15.11) 15.77 Indicate whether each of the following compounds is an acetal OO CH3 A CH3O CH2O CH2O CH A OO CH3 OOCH3 b A CH3O CH2O CH2OOO C OCH3 A CH3 CH3 c A CH3O CH2O CH2OOO C OOH A CH3 OOCH2 O CH2 O CH3 d A CH3 OC OCH2 O CH2 O CH3 A OOCH2 O CH2 O CH3 a 15.78 Indicate whether each of the following compounds is an acetal OO CH2O CH3 A CH3O CH2O CH A OO CH3 OOCH3 b A CH3OCH2OOO CO CH3 A CH3 H c A CH3O CH2O CH2O COOOCH3 A OH CH3 d A CH3O COOOCH3 A OO CH3 a 15.79 Draw the structural formula of the missing compound(s) in each of the following reactions OOCH3 A CH3O COOH ϩ ? A CH3 Hϩ b ? ϩ CH3O CH2OOH Hϩ OOCH3 A CH3O COOOCH3 ϩ H2O A CH3 H A CH3 OC OOOCH3 ϩ H2O A OO CH2OCH3 OH A CH3O CH2O C OOOCH3 ϩ CH3O CHOOH A A CH3 H c Hϩ ? ϩ H2O CH3 OCHOOO CH3 ϩ H2O A OOCH3 15.80 Draw the structural formula of the missing compound(s) in each of the following reactions OOCH3 a A Hϩ CH3 OCH2 O C OOH ϩ ? A CH3 OOCH3 A CH3O CH2 O COOOCH3 ϩ H2O A CH3 ϩ H b ? ϩ CH3 OCH2 OOH H A CH3 O CH2 OC OOOCH3 ϩ H2O A OOCH2 OCH3 OH c A Hϩ CH3O CH2O C OOOCH3 ϩ CH3O CHOOH A A CH3 H ? ϩ H2O d ? ϩ Hϩ Hemiacetal d ? Hemiacetal ? Alcohol ϩ ? Hϩ Alcohol CH3O CH2 O CHOOO CH3 ϩ H2O A OOCH3 15.81 Draw the structural formulas of the aldehyde (or ketone) and the two alcohols produced when the following acetals undergo hydrolysis in acidic solution OOCH3 a b OOCH3 A A CH3 OC OCH3 CH3 OCH A A OOCH3 OOCH3 c CH2 OCH3 A CH3 OOO COOOCH2 O CH3 A CH2 OCH3 OOCH3 d A CH3 O CH2 O CH2 O CH2 OC OOOCH3 A H Multiple-Choice Practice Test 15.82 Draw the structural formulas of the aldehyde (or ketone) and the two alcohols produced when the following acetals undergo hydrolysis in acidic solution a OO CH3 A CH3 O CH2 O CH A OO CH3 OOCH3 b A CH3 O CH2 O CO CH3 A OO CH3 c H A CH3 OCH2 OOOC OOO CH2 OCH3 A CH3 d OO CH2 OCH3 A CH3 OCH2 O CO CH2 O CH2 OCH3 A OO CH2 OCH3 15.83 Name each of the compounds in Problem 15.81 in the manner described in Section 15.11 15.84 Name each of the compounds in Problem 15.82 in the manner 471 Formaldehyde-Based Polymers (Section 15.12) 15.85 What are the structural characteristics associated with a network polymer? 15.86 What is a major current use for phenol–formaldehyde network polymers? 15.87 In phenol–formaldehyde polymer formation what are the inter- mediate compounds that are formed? 15.88 In a phenol–formaldehyde network polymer what type of “bridges” cross-link the various substituted phenols? Sulfur-Containing Carbonyl Groups (Section 15.13) 15.89 What type of compound is formed by replacement of the carbonyl oxygen atom with a sulfur atom? 15.90 What type of compound is formed by replacement of the carbonyl carbon atom with a sulfur atom? 15.91 Draw structural formulas for the following compounds a Thioformaldehyde b Methanethial c Thioacetone d Propanethione 15.92 Dimethyl sulfoxide (DMSO) is a sulfur analog of acetone in which the sulfur has substituted for the carbonyl carbon atom a Draw the structural formula for DMSO b Describe the “unusual” solubility properties of DMSO described in Section 15.11 A DD D ITIO NA L P R O BL L EMS 15.93 Explain each of the following 15.94 15.95 15.96 15.97 15.98 a The IUPAC name for the three-carbon aldehyde is propanal rather than 1-propanal b The IUPAC name for the three-carbon ketone is propanone rather than 2-propanone Each of the following compound names represents an impossible structure In each case, explain why a Methanone b 1-Chlorobutanal c 3-Methyl-3-pentanone d Cyclohexanal What is the characteristic structural feature of each of the following? a Hemiacetal b Acetal Draw the structural formula of the hemiacetal formed and then the acetal formed when each of the following compounds reacts with an excess of the reactant alcohol a Propanal and ethanol b Cyclohexanone and methanol The compound 4-hydroxybutanal can form an intramolecular cyclic hemiacetal Draw the structural formula of this cyclic hemiacetal Name the functional groups present in each of the following polyfunctional compounds a 4-Octen-2-one b 2-Methoxy-4-hydroxypentanal c 3-Hexyn-2-one d 4-Oxohexanal 15.99 Indicate whether each of the following compounds would be named as an alcohol, an aldehyde, or a ketone a O OH b O O H c OH H O d O OH O H multiple-Choice Practice Test 15.100 Which of the following statements concerning aldehydes and ketones is correct? a Aldehydes contain a carbonyl group but ketones not b Ketones contain a carbonyl group but aldehydes not c Both aldehydes and ketones contain a carbonyl group d Neither aldehydes nor ketones contain a carbonyl group 15.101 Which is the IUPAC name for the ketone ethyl propyl ketone? a 3-Pentanone b 4-Pentanone c 3-Hexanone d 4-Hexanone 472 Chapter 15 Aldehydes and Ketones 15.102 Which of the following compounds is a constitutional iso- 15.103 15.104 15.105 15.106 mer of acetone? a Formaldehyde b Acetaldehyde c Propionaldehyde d Butyraldehyde The physical state, at room temperature and pressure, for the simplest aldehyde and the simplest ketone is, respectively, which of the following? a Gas and gas b Gas and liquid c Liquid and gas d Liquid and liquid For which of the following molecular combinations is hydrogen bonding possible? a Aldehyde–aldehyde b Ketone–ketone c Aldehyde–ketone d Water–ketone A general method for the preparation of ketones is oxidation of which of the following? a 1Њ alcohols b 2Њ alcohols c 3Њ alcohols d Aldehydes Which of the following reactions is classified as a reduction reaction? a Alcohol to ketone b Alcohol to aldehyde c Aldehyde to alcohol d Aldehyde to carboxylic acid 15.107 In a hemiacetal, the hemiacetal carbon atom is bonded to which of the following? a Two hydroxyl groups b Two alkoxy groups c One hydroxyl group and one alkoxy group d Two hydroxyl groups and one alkoxy group 15.108 To produce an acetal from a ketone, the ketone must react with which of the following? a One alcohol molecule b Two identical alcohol molecules c Two different alcohol molecules d Two alcohol molecules, which may or may not be identical 15.109 What is the number of organic product molecules produced from the complete hydrolysis of an acetal molecule? a Two b Three c Four d Five ... 14 .14 14 .15 14 .16 14 .17 14 .18 14 .19 14 .20 14 . 21 Occurrence of and Uses for Phenols 4 21 Structural Characteristics of Ethers 422 Nomenclature for Ethers 423 Isomerism for Ethers 426 Physical and. .. 503 10 /19 /08 10 :59 :12 AM user-s1 31 /Volumes/MHSF/MH-SANFRAN/MHSF027/MHS 2880T_fm_i-xxviii.indd Page xxi 11 /25/08 6:58: 21 PM user-s1 31 /Users/user-s1 31/ Desktop/20 -11 -08 A GUIDE TO General, Organic,. .. Medicinal Plants 432 CHEMISTRY AT A GLANCE Alcohols, Thiols, Ethers, 433 and Thioethers Chapter 15 Aldehydes and Ketones 442 15 .1 15.2 15 .3 15 .4 15 .5 15 .6 15 .7 15 .8 15 .9 15 .10 The Carbonyl Group

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