Preview D K Singh Conceptual Problems in Organic Chemistry for Engineering and Medical Entrance Examinations 3rd Edition Pearson by D K Singh (2014)

Preview D K Singh Conceptual Problems in Organic Chemistry for Engineering and Medical Entrance Examinations 3rd Edition Pearson by D K Singh (2014) Preview D K Singh Conceptual Problems in Organic Chemistry for Engineering and Medical Entrance Examinations 3rd Edition Pearson by D K Singh (2014) Preview D K Singh Conceptual Problems in Organic Chemistry for Engineering and Medical Entrance Examinations 3rd Edition Pearson by D K Singh (2014) Preview D K Singh Conceptual Problems in Organic Chemistry for Engineering and Medical Entrance Examinations 3rd Edition Pearson by D K Singh (2014) Preview D K Singh Conceptual Problems in Organic Chemistry for Engineering and Medical Entrance Examinations 3rd Edition Pearson by D K Singh (2014)

Singh 3rd edition Conceptual Problems in D K Singh Conceptual Problems in Organic Chemistry 3/e covers all the essential concepts of organic chemistry through 2750 multiple-choice questions (MCQs) given in the book The MCQs have been designed in a manner to facilitate quick learning The current edition, a successor to the highly-appreciated previous edition, has three new chapters to give aspirants an extra edge to crack the examinations SALIENT FEATURES  Three new chapters on carbonyl compounds, ethers and amines, aromatic compounds, and bio-molecules  More than 2750 methodically-designed MCQs Conceptual Problems in for Engineering and Medical Entrance Examinations organic chemistry organic chemistry 3rd edition Conceptual Problems in organic chemistry for Engineering and Medical Entrance Examinations 3rd edition D K Singh Cover image: Shutterstock.com Size :172x235mm Spine : 19mm ISBN : 9789332517561 Title Sub Title Edition Authors / Editors Name With CD Red Band Territory line URL Price mQuest Conceptual Problems in Organic Chemistry [For Engineering and Medical Entrance Examinations] Third Edition D K Singh FM.indd 11/13/2013 3:00:07 PM Copyright © 2014 Dorling Kindersley (India) Pvt Ltd Published by Pearson India Education Services Pvt Ltd, CIN: U72200TN2005PTC057128, formerly known as TutorVista Global Pvt Ltd, licensee of Pearson Education in South Asia No part of this eBook may be used or reproduced in any manner whatsoever without the publisher’s prior written consent This eBook may or may not include all assets that were part of the print version The publisher reserves the right to remove any material in this eBook at any time ISBN 978-933-251-756-1 eISBN 978-933-258-207-1 Head Office: A-8 (A), 7th Floor, Knowledge Boulevard, Sector 62, Noida 201 309, Uttar Pradesh, India Registered Office: 4th Floor, Software Block, Elnet Software City, TS-140, Block & 9, Rajiv Gandhi Salai, Taramani, Chennai 600 113, Tamil Nadu, India Fax:  080-30461003, Phone: 080-30461060 www.pearson.co.in, Email: companysecretary.india@pearson.com FM.indd 11/13/2013 3:00:07 PM To my mother, for her immense love, patience and support FM.indd 11/13/2013 3:00:07 PM This page is intentionally left blank FM.indd 11/13/2013 3:00:07 PM Contents Foreword Preface to the Third Edition About the Author Chapter Hybridization, Resonance and Aromaticity Hybridization Resonance Aromaticity Chapter Isomerism Structural Isomerism Geometrical Isomerism Optical Isomerism Conformational Isomerism Chapter Substituent Effects, Reactive Intermediates, Acid-base and Electrophiles/Nucleophiles Substituent Effects Reactive Intermediates Acid-base Electrophiles/Nucleophiles Chapter Reaction Mechanism FM.indd Nucleophilic Substitutions Elimination Reactions Electrophilic Addition Reactions Nucleophilic Addition Reactions Electrophilic Aromatic Substitutions Nucleophilic Aromatic Substitutions vii ix x – 28 29 – 100 101 – 168 169 – 234 11/13/2013 3:00:07 PM vi  FM.indd n  Contents Chapter Alkanes, Alkenes and Alkynes Alkenes Alkynes Chapter Alkyl Halides and Alcohols Alkyl Halides Alcohols Chapter Carbonyl Compounds, Ethers and Amines Aldehydes/Ketones Amines Ethers 235 – 320 Alkanes 321 – 410 411 – 468 Carboxylic Acids and their Derivatives Chapter 8 Aromatic Compounds Aromatic Compounds 469 – 498 Chapter 9 Bio-molecules Carbohydrates 499 – 518 Amino Acids Peptides 11/13/2013 3:00:07 PM Foreword Chemistry is an ever-expanding branch of science that is based on well-established concepts Most of the concepts are widely accepted and are often experimentally verified Organic chemistry in particular deals with covalently linked carbon compounds The stability of an organic compound in terms of its internal energy and rate of formation/decomposition can be predicted based on various physical concepts A fair understanding of the possible involvement of intermediates and transient species and the kind of interaction among two or more reactants would enable us to propose a feasible reaction pathway Organic chemists have in their arsenal a plethora of reagents and conditions to carry out various synthetic transformations Whether or not a reagent is suitable for a specific transformation can be predicted only through clear understanding of its reactivity Man has developed various concepts on reactivity and selectivity by looking at mother nature Her ability to generate numerous biomolecules that are indispensable to create and sustain life on earth has been a true inspiration to man He cleverly applied those concepts in science and in everyday life Dr Singh has developed an invaluable resource based on concepts in organic chemistry for the benefit of students who are keen to learn more and prepare themselves for competitive examinations by intense problem solving Enormous efforts have been expended for framing this extensive collection of single choice questions Dr Singh took extraordinary care to ensure that questions with different levels of difficulty are included in order to keep the students of all levels interested in the subject This unique collection of diverse questions enables the students to examine their own comprehension, conceptual understanding, logical and analytical thinking as well as time management skills This book is far superior to many other national level competitive examination guides The coverage of the subject is so exhaustive that the students would find every question a learning experience and say good bye to many guide books/question banks that contain monotonous questions This is primarily due to Dr Singh’s penchant for physical organic chemistry He is well aware that understanding of theoretical, mechanistic and stereochemical concepts in organic chemistry is absolutely necessary to logically tackle even synthetic puzzles FM.indd 11/13/2013 3:00:07 PM viii  n  Foreword I am certain that a student who succeeds in answering most of Dr Singh’s questions will be one of the top ranking students in the national level competitive examinations for undergraduate admission I consider this book as an outstanding aid and recommend it wholeheartedly to those aspiring for admission to leading higher education institutions This book would be an excellent reference book for postgraduate students and teachers as well Irishi N.N Namboothiri Professor Department of Chemistry Indian Institute of Technology Bombay Mumbai 400 076 FM.indd 15 March 2013 11/13/2013 3:00:07 PM Preface to the Third Edition Organic Chemistry is not a formative science It requires an interest in the nature and reaction of molecules In other words, realization is the best way to learn organic chemistry because most of the problems are based on application of concepts Therefore, students should have a clear concept of the subject and then learn to apply those concepts in solving problems While formulating and designing the questions for this book, I had to consider all angles of each topic included in the syllabus This book effectively catalyses the process of learning the subject In fact, questions are designed to encourage students to learn more and more of Organic Chemistry The third edition has been updated and now includes three new chapters on carbonyl compounds, etheres and amines, aromatic compounds and biomolecules I am sure students will find this useful I extend my sincere thanks to Mr Mohammad Ashfaq for his valuable feedback and suggestions I will appreciate your invaluable suggestions and feedback to improve future editions of this book D K Singh FM.indd 5/5/2014 1:08:32 PM 14  n  Conceptual Problems in Organic Chemistry O 87 O I II O 91 O III IV Among these compounds, which one has maximum resonance energy? b II a I d IV c III 88 I CH3COOH II CH3CONH2 III CH3COF Among these compounds, the correct order of resonance energy is b III > II > I a I > II > III c d II > III > I II > I > III 89 OCH3 I II III OCH3 OCH3 II I – + CH2 = CH – CH – CH = CH – CH2 III – + CH2 – CH = CH – CH = CH – CH2 Among these three canonical structures, (though more are possible) what would be their relative contribution in the hybrid? b III > II > I a I > II > III d III > I > II c I > III > II CH2 = CH – OCH3 III Among these compounds, the correct order of resonance energy is b II > I > III a I > II > III d I > III > II c III > I > II – + CH2 – CH = OCH3 CH2 = CH – N II II CH2 = CH – CH = CH – CH =CH2 II I Among these compounds the correct order of resonance energy is b II > I > III a III > I > II d III > II > I c I > II > III I I 93 90 – + CH2 – CH = OH Which of the following statements is true about this resonating system? a Contribution of II is more than that of I in resonance hybrid b Contribution of I is increased by a polar solvent c Contribution of II is increased by a polar solvent d Relative contributions of I and II are independent of solvent 92 CH2 = CH – OH CH3 CH3 – + CH3 CH2 – CH = N CH3 Which of the following statements is true about the contribution of I and II in respective resonance hybrids? a I contributes more than II b II contributes more than I c Both I and II contribute equally d none of these Hybridization, Resonance and Aromaticity  n  15 94 Heat of hydrogenation of cyclohexene is –28.6 kcal/mol and that of benzene is –49.8 kcal/mol Then resonance energy of benzene will be b 39 kcal/mol a 46 kcal/mol d 30 kcal/mol c 36 kcal/mol 96 Heat of hydrogenation of CH3-CH=CH2 is –30 kcal/mol and resonance energy of 1,3butadiene is 3 kcal/mol What will be the heat of hydrogenation of 1,3-butadiene? b –57 kcal/mol a –63 kcal/mol d (c) –27 kcal/mol –54 kcal/mol CH3 CH3 CH2 III CH2 The heats of hydrogenation of these compounds will be in the order as b III > II > I a I > II > III d II > I > III c II > III > I 100 I I II III Among these compounds, the order of heats of hydrogenation is b III > II > I a I > II > III d II > III > I c II > I > III III I CH3 CH2 II 98 CH2 II 97 CH3 I 95 Diene Heat of Hydrogenation CH2 = CH-CH=CH-CH3 –54.1 kcal/mol I CH3-CH=C=CH-CH3 –70.5 kcal/mol II CH2=CH-CH2-CH=CH2 –60.2 kcal/mol III Examine these dienes and their heat of hydrogenations Now, what will be the stability order among these dienes? b II > III > I a I > II > III d II > I > III c I > III > II CH3 99 II III Among these compounds, the order of heats of hydrogenation is b III > II > I a II > III > I c d I > II > III II > I > III 3 4 Examine these canonical structures of naphthalene Now, which of the following statements is true about C1-C2 and C2-C3 bond lengths? a Both bonds are of same length b C1-C2 bond is longer than C2-C3 bond c C2-C3 bond is longer than C1-C2 bond d It is not possible to judge the bond length because given structures are tautomers 16  n  Conceptual Problems in Organic Chemistry 101 O N 104 Which of the following compounds has longest C-O bond? O O NO2 NO2 Which of the following statements is true about this molecule? a C5-N bond is longer than C1-N and C3-N bonds b C5-N bond is shorter than C1-N bond and latter is shorter than C3-N bonds c C1-N and C3-N bonds are of same length but longer than C5-N bond d All three C-N bonds are of same length 102 I Which of the following statements is true about this molecule? a C1-C2 and C3-C4 bonds are of same length b C1-C2 bond is shorter than C3-C4 bond c C1-C2 bond is longer than C3-C4 bond d C1-C2 and C2-C3 bonds are of same length 103 NH2 NH2 NH2 COOCH3 III The correct order of C-N bond length among these compounds is b III > II > I a I > II > III c d III > I > II II > I > III b O O c d CH3O - CH = CH - NO2 I CH3O - CH = CH2 II CH2 = CH2 III Which of the following orders of C-C bond lengths is correct among these compounds? b III > II > I a I > II > III c d II > I > III III > I > II 105 106 Among the following compounds, the correct order of C-C bond length is a C2H6 > C2H4 > C6H6 > C2H2 b C2H6 > C6H6 > C2H4 > C2H2 c C2H4 > C2H6 > C2H2 > C6H6 d C2H6 > C2H4 > C2H2 > C6H6 (C6H6 is benzene) 107 Among the following compounds, C1-C2 bond is shortest in C ≡ CH a II I a b c d 1 C = CH2 CH2 – CH3 C ≡ CH Hybridization, Resonance and Aromaticity  n  17 108 H2O2 O3 O2 Among these molecules, the correct order of O-O bond length is a H2O2 > O3 > O2 b O2 > O3 > H2O2 c O3 > H2O2 > O2 d O3 > O2 > H2O2 113 CH3 CH3 – a HCOO c CO2 110 I II Cl OH OH NO2 NO2 I II III Among these compounds, the correct order of C-O bond length is b I > II > III a II > I > III d III > I > II c III > II > I 112 Which of the following compounds do not have all C-C bonds of same length? a CH3 c + N II CH3 CH3 CH3 – a H c H C O C b H H d NH2 H C O C F OH 115 H - O - C = N H - N = C = O (Cyanic acid) ( Isocyanic acid) Loss of proton from these two acids produces a same anion b different anions c same cation d different cations 116 I CH2 = CH – CH – CH3 Br II b d III Among these compounds, the correct order of ring-N-bond length is b III > II > I a III > I > II d II > III > I c I > III > II 114 Among the following compounds which one has longest C-O bond? O O CH3 I Cl OH N b CO3 2– d HCOOH III Cl IV Cl Among these compounds, which one has shortest C-Cl bond? b II a I d IV c III 111 CH3 CH3 109 Which of the following species does not have all C-O bonds of same length? CH3 N CH2 – CH = CH – CH3 Br Ionization of these compounds produces – Br and b different anions a same anion d different cations c same cation 18  n  Conceptual Problems in Organic Chemistry + OH 117 I CH3 – C – N CH3 CH3 OH OH 121 Which of the following systems is the correct proposition given by kekule regarding the structure of benzene? CH3 CH3 – C – N + CH3 II + CH3 CH3 – C = N CH3 The stability order of these canonical structures is b III > I > II a I > II > III d II > III > I c I > III > II III 118 CH2 = CH – OCH3 – + CH2 – CH = OCH3 I II On moving from gas phase to water as solvent, the contribution of II in the resonance hybrid a increases b decreases c remains constant d this question is not valid O 119 The π-electron density on the carbonylic oxygen is maximum in which of these compounds? b II a I d c III same in all In this compound, how many sites are – CH O available for the attack of ? b a d c a b c d 122 Which of the following systems is the correct proposition given by Huckel regarding the structure of benzene? a b c d O 120 I CH3 – C – NH – CH2 –Ph O II CH3 – C – NH – Ph O III CH3 – C – NH NO2 123 Which of the following statements is not correct about aromaticity? a Aromaticity is born out of resonance b All resonating molecules are aromatic c To be aromatic resonance energy should be high d Only cyclic molecules may be aromatic Hybridization, Resonance and Aromaticity  n  19 124 Which of the following structural conditions is not required for a molecule to become aromatic? a Molecule should be cyclic b Ring should be planer c Ring must contain 4n + 2 number of πelectrons involved in cyclic resonance, where, n = 0, 1, 2, 3 d Ring must contain 4n number of πelectrons involved in cyclic resonance, where n = 1, 2, 3 125 Which of the following structural conditions is not required for a molecule to become anti-aromatic? a Molecule should be cyclic b Ring should be planer c Ring must contain 4n + 2 number of πelectron involved in cyclic resonance d Ring must contain 4n number of π-electrons involved in cyclic resonance Heat of hydrogenation 126 I – 25.6 k cal/mole II – 55.5 k cal/mole creases while on moving from II to III stability increases b On moving from I to II stability in creases while on moving from II to III stability decreases c On moving from I to II to III, stability decreases gradually d On moving from I to II to III stability increases gradually 127 Which of the following statements about aromaticity/antiaromaticity is correct? a In the process of becoming aromatic, π-electron energy of the molecule decreases while in the process of becoming antiaromatic, π-electron energy increases b In the process of becoming aromatic π-electron energy of the molecule increases while in the process of becoming antiaromatic, π-electon-energy of the molecule decreases c In the process of becoming either aromatic or antiaromatic, π-electronenergy of the molecule increases d In the process of becoming either aromatic or antiaromatic, π-electronenergy of the molecule decreases 128 III – 49.8 k cal/mole On moving from cyclohexene (I) to 1,3cyclohexadiene (II) one C=C bond is increased This is turn, increases heat of hydrogenation from –28.6 to –55.5 kcal/mole Similarly, on moving from 1,3-cyclohexdiene (II) to benzene (III) one C=C bond is increased Even then, heat of hydrogenation is decreased from –55.5 kcal/mole to –49.8 kcal/mole Now, which of the following statements explains this abnormally lower heat of hydrogenation of benzene? a On moving from I to II stability de- – + II III I Which of these cyclopropene systems is aromatic? b II a I d c III all of these 129 – + II III I Which of these cyclopropene systems is anti-aromatic? b II a I d all of these c III n  Conceptual Problems in Organic Chemistry – – + I II III Which of these species is aromatic? b II only a I only d both II and III c III only 131 + + – + – I II III Which of these species is anti-aromatic? b II only a I only d both II and III c III only 132 – + I II III Which of these species is aromatic? b II a I d all c III 136 Which of the following compounds is not aromatic? O a b O c a 135 Which of the following annulenes is aromatic? b [10]-Annulene a [8]-Annulene d none c [12]-Annulene O b O c O d 138 Which of the following π-molecular orbital energy diagrams is correct for benzene? a Energy b c d Energy – + I II III Which of these species is aromatic? b II a I d all of these c III O O 137 Which of the following species is not aromatic? – + – + I II III Which of these species is anti-aromatic? b II only a I only d both II and III c III only 134 d O 133 O – Energy 130 Energy 20  139 Which of the following π-molecular orbital-energy diagrams is correct for Energy Hybridization, Resonance and Aromaticity  n  21 d ? Energy a 141 Which of the following π-molecular orbital-energy diagrams is correct for ? a Energy b c d c d 140 Which of the following π-molecular orbital energy diagrams is correct for ? Energy – a Energy Energy b Energy Energy Energy Energy + 142 Which of the following π-molecularorbital-energy diagrams is correct for (Tropylium cation)? a b b c Energy Energy Energy Energy + 22  n  Conceptual Problems in Organic Chemistry c N Energy Energy 145 d 143 Which of the following π-molecular obital-energy diagrams is correct for ? Energy – a b Energy c d 150 144 Which of the following compounds is aromatic? a N (Pyridine) 147 Lone-pair of electrons on nitrogen atom of pyridine is not delocalized with π- electrons because a it is in p-orbital b it is in sp3-orbital c it is in sp2 orbital which cannot overlap with p-orbitals on adjacent carbon atoms d it is in sp-orbital 149 Lone pair of electron on nitrogen atom of pyrrole is delocalized with π-electrons because a it is in p-orbital which can overlap with p-orbitals on adjacent carbon atoms b it is in sp2 orbital c it is in sp orbital d it is in sp3 orbital Energy 146 Lone-pair of electrons on nitrogen atom of pyridine is in b sp-orbital a p-orbital c d sp -orbital sp2-orbital 148 Nitrogen atom of pyrrole is b sp2- hybridized a sp3-hybridized c d not-hybridized sp-hybridized Energy Nitrogen atom of pyridine is b sp2 hybridized a sp3 hybridized c d sp hybridized not hybridized c O Furan b N H (Pyrrole) d all of these O Furan Oxygen atom of furan is b sp2-hybridized a sp3- hybridized c d sp- hybridized not hybridized 151 Which of the following statements is true about furan? a One lone pair of electrons is in sp2-orbital while the other is in p-orbital Hybridization, Resonance and Aromaticity  n  23 b Both lone pairs of electrons are in sp2orbitals c Both lone-pairs of electrons are in porbitals d Both lone pairs of electrons are in sp3orbitals 152 – + =N=N The most stable canonical structure of this molecule is a b – c – + NºN – N=N c Br 155 Ease of ionization to produce carbocation and bromide ion under the treatment of Ag + will be maximum in which of the following compounds? O a c Br d Br 156 Ease of ionization to produce carbocation and bromide ion under the treatment of Ag + will be maximum in which of the following compounds? Br Br b a The most stable canonical structure of this molecule is – O + c b O – + – O + b Br d All are equally stable a d Br – + N=N O b Br 153 a Br + d + O 154 Which of the following compounds is soluble in water and has very high melting point? OCH3 Br c Br d OCH3 157 Ease of ionization to produce carbocation and bromide ion under the treatment of Ag + will be maximum in which of the following compounds? a c Br OCH3 Br b Br d Br 24  n  Conceptual Problems in Organic Chemistry 158 Ease of ionization to produce carbocation and bromide ion under the treatment of Ag + will be maximum in which of the following compounds? a b c d 159 O O Br Br N Br Ph N Br CH3 O N – O The barrier for rotation about the indicated bond is only 14 kcal/mol This barrier is much lower than the barrier for rotation about C=C bond in ethylene The smaller barrier in this compound is due to a dipolar structure b lack of resonance c enolization d combination of a and b 161 Which of the following compouds will be aromatic on treatment with LiAlH4? a c O O d THF P p will be a 2– b 2+ c d mixture of a and b 2k + Cl SbCl Cl p will be a 2– b 2+ c d mixture of a and b 164 – 2SbCl HClO O p will be a + P – ClO OH b – OH b K 163 H I II III Which of the following choice is the correct order of resonance energy of these molecules? b II > I > III a I > II > III d III > I > II c III > II > I 160 162 + H H c O d mixture of a and b O ClO P Hybridization, Resonance and Aromaticity  n  25 165 HClO P p will be a + – ClO b – + H c H ClO d mixture of a and b a + b – c mixture of a and b d none of these 166 Ag ClO Cl a + b c mixture of a and b d none of these – ClO + Ag 167 Ph Ph p will be Ph a 2+ Ph Ph Ph Br Ag BF Br Ph Ph Ph Ph – 2BF4 + 2Ag b Ph Ph c mixture of a and b d none of these 2– K BuLi P b c CH3 O – + CH2 Na d none of these 170 I P II III Among these aromatic compounds the correct order of resonance energy per ring is b III > II > I a I > II > III c III > I > II d II > I > III 171 P NaH CH2 p will be ONa a P p will be – O CH2 ONa 168 p will be 169 CH3 I II Which of the following orders is correct for the π-electron energy of these two compounds? 26  n  Conceptual Problems in Organic Chemistry a I > II b II > I c I = II d there is nothing like π-electron en- ergy 172 I II Which of the following orders is correct for the π-electron energy of these two compounds? a I > II b II > I c I = II d there is nothing like π-electron-energy Compound (I) is highly stable and thus least reactive On the other hand, compound (II) is unstable and thus highly Reactive Which of the following reasons can explain this difference in stabilities of these two compounds a Compound (I) exist mainly in dipolar structure as + – O In this structure ring is aromatic On the other hand, such polorization in compound (II) leads to anti-aromatic ring as b Dipole moment of compound (II) is more than that of compound (I) c Resonance energy of compound (II) is more than that of compound (I) d none of these + 173 I II Which of the following order is correct for the π-electron energy of these two compounds? a I > II b II > I c I = II d there is nothing like π-electron energy 174 176 + CH = CH – CH2 + II I Which of the following orders is correct for π-electron energy of these cations? a I > II b II > I c I = II d there is nothing like π-electron energy 175 O II I (Cycloheptatrienone) (Cyclopentadienone) I II III The barrier for rotation about the indicated bonds will be maximum in which of these three compounds? b II a I d same in all c III 177 O O – O N – H III I II The aromatic character is maximum in which of these three compounds? b II a I c d III same in all Hybridization, Resonance and Aromaticity  n  27 178 O H I II III The aromatic character is maximum in which of these three compounds? b II a I c d III same in all 179 O – OH O – CHO – O – C – CH3 – C – OCH3 182 Which of the following annulenes is neither aromatic nor anti-aromatic but a simple polyene? b [8] - annulene a [4] - annulene – NH2 I II III Arrange these groups in decreasing order of their electron-donating power in resonance b II > I > III a III > I > II c d III > II > I I > III > II 180 N I II III Arrange these groups in decreasing order of their electron-withdrawing power in resonance b I > II > III a III > II > I c d I > III > II II > III > I 181 - CH = CH2 - CH = CH - OCH3 I II - CH = CH - NO2 III c [10] - annulene d Both b and c 183 O – C– NH2 Arrange these groups in decreasing order of their electron-donating power in resonance b II > III > I a I > II > III c d II > I > III III > I > II (Pyrene) Which of the following statements is true about pyrene in addition reactions? a The central π-bond (encircled) is more reactive than all the peripheral π-bonds b The central π-bond is less reactive than all the peripheral π-bonds c All π-bond are equally reactive d Addition reactions are not possible on this molecule 28  n  Conceptual Problems in Organic Chemistry Answers 11 21 31 41 51 61 71 81 91 101 111 121 131 141 151 161 171 181 c c a c c d 12 22 32 42 52 b b 62 a 72 b b c b c c c d a b a a b c 82 92 102 112 122 132 142 152 162 172 182 c d b c a a b b c c b c a a d 13 23 33 43 53 a d a c d c 63 b 73 c 83 93 103 113 123 133 143 153 163 173 183 a b c a b b b b b b a 14 24 34 44 54 b a c a b c 64 c 74 c 84 94 104 114 124 134 144 154 164 174 b c b c d b d d a a 15 25 35 45 55 d b a b a a 65 d 75 d 85 95 105 115 125 135 145 155 165 175 c c a a c d b b a a 16 26 36 46 56 66 76 86 96 106 116 126 136 146 156 166 176 a c b a a d b d a b b c a d d c a b 17 27 37 47 57 d c c b b c 67 c 77 b 87 97 107 117 127 137 147 157 167 177 c c d b a b c a a c 18 28 38 48 58 68 78 88 98 108 118 128 138 148 158 168 178 d c a b a c d a d a a a c b b d b a 19 29 39 49 59 69 79 89 99 109 119 129 139 149 159 169 179 c c c a d d d c c b d b b b a c b a 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 a c d c b b c c b c a a d b b a a b .. .Conceptual Problems in Organic Chemistry [For Engineering and Medical Entrance Examinations] Third Edition D K Singh FM.indd 11/13/2013 3:00:07 PM Copyright © 2014 Dorling Kindersley (India)... your invaluable suggestions and feedback to improve future editions of this book D K Singh FM.indd 5/5/2014 1:08:32 PM About the Author Devendra Kaumar Singh trains students appearing for the medical. .. competitive examinations for undergraduate admission I consider this book as an outstanding aid and recommend it wholeheartedly to those aspiring for admission to leading higher education institutions