APPENDIX 2 1.17 The H--B--H angles in BH4 are 109.5(tetrahedral 1.18(b)Tetrahedral;(c)linear, (d) trigonal planar 1.19(b)Oxygen is negative end of dipole moment directed along bisector of H-O-H angle; (c)no dipole moment;(d) dipole moment directed along axis of C-Cl bond, with chlorine at negative end, and carbon and hydrogens partially positive; (e)dipole moment directed along bisec tor of H-C-H angle, with oxygen at negative end;(f) dipole moment aligned with axis of lin ear molecule, with nitrogen at negative end. 1.20 The sp"hybrid state of nitrogen is just like that of carbon except nit has one mot electron. Each N-H bond in NH3 involves overlap of an sp hybrid orbital of n with a 1s orbi of hydrogen. The unshared pair of NH, occupies an sp'orbital. 十+十2#+十 2y3++ Ground electronic Higher energy electronic sp'Hybrid state of nitrogen state of nitrogen 1.21 nd silicon are both sp-hybridized. The C-Si bond involves overlap of a half- filled of carbon with a half-filled sp' hybrid orbital of silicon. The C-H and Si-H bonds hydrogen 1s orbitals and sp hybrid orbitals of C and Si, respectively. The princi- pal quantum number of the valence orbitals of silicon is 3 1.22(b)sp; (c)carbon of CH2 group is sp and carbon of C=O is sp; (d)two doubly bonded carbons are each sp, while carbon of CH, group is sp;(e)carbon of C=O is sp and carbons of CH3 group are sp;(f) two doubly bonded carbons are each sp, and carbon bonded to nitro- CHAPTER 2 Ketone≠ Carboxylic acid 2.2 CHa(CH2b26CH 2.3 The molecular formula is CuH24; the condensed structural formula is CH3(CH)CH Forward Main Menu TOC Study Guide Toc Student OLCMHHE Website
APPENDIX 2 A-11 (d) and 1.17 The H±B±H angles in BH4 are 109.5° (tetrahedral). 1.18 (b) Tetrahedral; (c) linear; (d) trigonal planar 1.19 (b) Oxygen is negative end of dipole moment directed along bisector of H±O±H angle; (c) no dipole moment; (d) dipole moment directed along axis of C±Cl bond, with chlorine at negative end, and carbon and hydrogens partially positive; (e) dipole moment directed along bisector of H±C±H angle, with oxygen at negative end; (f) dipole moment aligned with axis of linear molecule, with nitrogen at negative end. 1.20 The sp3 hybrid state of nitrogen is just like that of carbon except nitrogen has one more electron. Each N±H bond in NH3 involves overlap of an sp3 hybrid orbital of N with a 1s orbital of hydrogen. The unshared pair of NH3 occupies an sp3 orbital. 1.21 Carbon and silicon are both sp3 -hybridized. The C±Si bond involves overlap of a half- filled sp3 orbital of carbon with a half-filled sp3 hybrid orbital of silicon. The C±H and Si±H bonds involve hydrogen 1s orbitals and sp3 hybrid orbitals of C and Si, respectively. The principal quantum number of the valence orbitals of silicon is 3. 1.22 (b) sp2 ; (c) carbon of CH2 group is sp2 , and carbon of CœO is sp; (d) two doubly bonded carbons are each sp2 , while carbon of CH3 group is sp3 ; (e) carbon of CœO is sp2 , and carbons of CH3 group are sp3 ; (f) two doubly bonded carbons are each sp2 , and carbon bonded to nitrogen is sp. CHAPTER 2 2.1 2.2 CH3(CH2)26CH3 2.3 The molecular formula is C11H24; the condensed structural formula is CH3(CH2)9CH3. Ketone Carboxylic acid OH O OH HO O Energy 2p 2s Ground electronic state of nitrogen 2sp3 sp3 Hybrid state of nitrogen 2p 2s Higher energy electronic state of nitrogen B O O O B O O O B O O O B O O O
A-12 APPENDIX 2 2.4 CH3CH,CHCH, CH3 or CH CH CH3 O and CH3 CH, CCH3 or 2.5 (b)CH3(CH2)26CH3;(c)undecane 2.6 2.7 (b)CH3 CH2CH_CH2CH3 (pentane),(CH3)2 CHCH2CH3 (2-methylbutane),(CH3)C(2, 2 dimethylpropane);(c)2, 2, 4-trimethylpentane;(d)2, 2, 3, 3-tetramethylbutane 2.8 CH3 CH2CH2CH2CH2-(pentyl, primary): CH3 CH2CH2CHCH3(1-methylbutyl, sec- dary): CH3 CH2CHCH2 CH3(1-ethylpropyl, secondary );( CH3)2CHCH2CH2-(3-methylbutyl, primary ) CH3 CH2CH(CH3)CH2-(2-methylbutyl, primary);(CH3)2CCH2CH3 (1, I-dimet propyl, tertiary); and(CH3)2CHCHCH,(1, 2-dimethylpropyl, secondary) 2.9 (b)4-Ethyl-2-methylhexane:(c)8-ethyl-4-isopropyl-2, 6-dimethyldecane 2.10 (b) 4-lsopropyl-1, 1-dimethylcyclodecane;(c) cyclohex 2.11 2, 2, 3,3-Tetramethylbutane(106C): 2-methy heptane(116.C); octane(126C):nonane (151°C) 6CO,+6H0 21313,313kJ/mol 2.14 Hexane (CH3,CH,CH,CH,CH3)> pentane(CH, CH,CH2 CH,CH3)>isopentane [(CH3)2 CH3I neopentane [(CH3)Cl 2.15(b)Oxidation of carbon;(c) reduction of carbon CHAPTER 3 3.1 (b) Butane;(c)2-methylbutane; (d)3-methy lhexane 3.2 Red circles gauche: 60 and 300%. Red circles anti: 180. Gauche and anti occur only in staggered conformations; therefore, ignore the eclipsed conformation 40°,360°) 3.3 Shape of potential energy diagram is identical with that for ethane(Figure 3.4). Activation energy for rotation about the C-C bond is higher than that of ethane, lower than that of butane. 3.5 (b) Less stable;(c) methyl is equatorial and down Forward Main Menu TOC Study Guide Toc Student OLCMHHE Website
A-12 APPENDIX 2 2.4 2.5 (b) CH3(CH2)26CH3; (c) undecane 2.6 2.7 (b) CH3CH2CH2CH2CH3 (pentane), (CH3)2CHCH2CH3 (2-methylbutane), (CH3)4C (2,2- dimethylpropane); (c) 2,2,4-trimethylpentane; (d) 2,2,3,3-tetramethylbutane 2.8 CH3CH2CH2CH2CH2± (pentyl, primary); (1-methylbutyl, secondary); (1-ethylpropyl, secondary); (CH3)2CHCH2CH2± (3-methylbutyl, primary); CH3CH2CH(CH3)CH2± (2-methylbutyl, primary); (1,1-dimethylpropyl, tertiary); and (1,2-dimethylpropyl, secondary) 2.9 (b) 4-Ethyl-2-methylhexane; (c) 8-ethyl-4-isopropyl-2,6-dimethyldecane 2.10 (b) 4-Isopropyl-1,1-dimethylcyclodecane; (c) cyclohexylcyclohexane 2.11 2,2,3,3-Tetramethylbutane (106°C); 2-methylheptane (116°C); octane (126°C); nonane (151°C) 2.12 2.13 13,313 kJ/mol 2.14 Hexane (CH3CH2CH2CH2CH2CH3) pentane (CH3CH2CH2CH2CH3) isopentane [(CH3)2CHCH2CH3] neopentane [(CH3)4C] 2.15 (b) Oxidation of carbon; (c) reduction of carbon CHAPTER 3 3.1 (b) Butane; (c) 2-methylbutane; (d) 3-methylhexane 3.2 Red circles gauche: 60° and 300°. Red circles anti: 180°. Gauche and anti relationships occur only in staggered conformations; therefore, ignore the eclipsed conformations (0°, 120°, 240°, 360°). 3.3 Shape of potential energy diagram is identical with that for ethane (Figure 3.4). Activation energy for rotation about the C±C bond is higher than that of ethane, lower than that of butane. 3.4 (b) (c) (d) 3.5 (b) Less stable; (c) methyl is equatorial and down X A 3 X A 3 X A 9O2 6CO2 6H2O (CH3)2CHCHCH3 (CH3)2CCH2CH3 CH3CH2CHCH2CH3 CH3CH2CH2CHCH3 CH or and or 3CHCHCH3 CH3 CH3 CH3CH2CCH3 CH3 CH3 CH or 3CH2CHCH2CH3 CH3
APPENDIX 2 A-13 (CH3)3 3.7 Ethylcyclopropane: 3384 kJ/mol(808.8 kcal/mol); methylcyclobutane: 3352 kJ/mol(801.2 3.8 1, 1-Dimethylcyclopropane, ethylcyclopropane, methylcyclobutane, and cyclopentane 3.9 cis-1, 3, 5-Trimethylcyclohexane is more stable (b)H3C H C(CH3)3 3.11 CH=CH, and CH2 3.12 CH3 CH3 CH 313(b) 3.14 CHAPTER 4 CH3,CH2CI CH3CHCH2CH Substitutive name I-Chlorobutane n-Butyl chloride sec-Butyl chloride butyl chloride methylpropyl chloride CH3) CI 1-Chloro-2-methylpropane 2-Chloro-2-methylpropane sobutyl chlorid tert-Butyl chloride Forward Main Menu TOC Study Guide Toc Student OLCMHHE Website
APPENDIX 2 A-13 3.6 3.7 Ethylcyclopropane: 3384 kJ/mol (808.8 kcal/mol); methylcyclobutane: 3352 kJ/mol (801.2 kcal/mol) 3.8 1,1-Dimethylcyclopropane, ethylcyclopropane, methylcyclobutane, and cyclopentane 3.9 cis-1,3,5-Trimethylcyclohexane is more stable. 3.10 (b) (c) (d) 3.11 3.12 Other pairs of bond cleavages are also possible. 3.13 (b) (c) (d) 3.14 CHAPTER 4 4.1 Substitutive name: Functional class names: CH3CH2CH2CH2Cl 1-Chlorobutane n-Butyl chloride or butyl chloride 1-Chloro-2-methylpropane Isobutyl chloride or 2-methylpropyl chloride (CH3)2CHCH2Cl CH3CHCH2CH3 Cl 2-Chlorobutane sec-Butyl chloride or 1-methylpropyl chloride 2-Chloro-2-methylpropane tert-Butyl chloride or 1,1-dimethylethyl chloride (CH3)3CCl N CH3 CH3 CH3 CH2 CH3 CH2 CH3 CH3 CH2 CH3 CH CH2 and CH2 C(CH3)3 H H CH3 C(CH3)3 H H3C H C(CH3)3 H H H3C CH3 C(CH3)3
A-14 APPENDIX 2 CH3 CH, CH, CH,OH CH3CHCH, CH OH sec-Butyl alcohol -methylpropyl alcohol 2-Methyl-1-propano 2-Methy Isobutyl alcohol 4.3 CHCH, CH, CH,OH CH3 CHCH, CH3 (CH3)2CHCH,OH (CH3)3COH 4.4 The carbon-bromine bond is longer than the carbon -ehlorine bond; therefore. although the harge e in the dipole moment expression u = e. d is smaller for the bromine than for the chlo- rine compound, the distance d is greater 4.5 Hydrogen bonding in ethanol(CH3CH2OH) makes its boiling point higher than that of dimethyl ether (CHaOCH,), in which hydrogen bonding is absent Base Acid Conjugate acid Conjugate base 4.7 K=8X10; hydrogen cyanide is a weak acid. 4.8 Hydrogen cyanide is a stronger acid than water; its conjugate base(Cn ) is a weaker base than hydroxide(Ho) 4.9(CH3)3C-0:+ (CH3)3C-0:+;Cl Base Conjugate base 4.10 Greater than 1 4.11(CH3)3C-0---H---Cl (c)CH3(CH2)12CH2OH HB(CH, CH2)3 CCI H2O 4.12 (b)(CH3 CH2)3COH HCI CH3(CH2)12 CH, Br H,O 4.13(CH3)CCH2CH3 4.14 1-Butanol: Rate-determining step is bimolecular; therefore, SN2 1. CH3CH2 CH2CH20: H--Br:->CH3 CH_ CH2 CH,0++ Forward Main Menu TOC Study Guide Toc Student OLCMHHE Website
A-14 APPENDIX 2 4.2 4.3 4.4 The carbon—bromine bond is longer than the carbon—chlorine bond; therefore, although the charge e in the dipole moment expression e d is smaller for the bromine than for the chlorine compound, the distance d is greater. 4.5 Hydrogen bonding in ethanol (CH3CH2OH) makes its boiling point higher than that of dimethyl ether (CH3OCH3), in which hydrogen bonding is absent. 4.6 4.7 Ka 8 1010; hydrogen cyanide is a weak acid. 4.8 Hydrogen cyanide is a stronger acid than water; its conjugate base (CN) is a weaker base than hydroxide (HO). 4.9 4.10 Greater than 1 4.11 4.12 (b) (CH3CH2)3COH HCl ±£ (CH3CH2)3CCl H2O (c) CH3(CH2)12CH2OH HBr ±£ CH3(CH2)12CH2Br H2O 4.13 (CH3)2C CH2CH3 4.14 1-Butanol: Rate-determining step is bimolecular; therefore, SN2. 1. CH3CH2CH2CH2O H H Br Br fast H CH3CH2CH2CH2O H (CH3)3C O Cl H H Cl Conjugate base H Cl Acid (CH3)3C O H O Base H (CH3)3C O H O Conjugate acid Cl Conjugate base H3N H Conjugate acid H3N Base H Cl Acid CH3CH2CH2CH2OH Primary CH3CHCH2CH3 OH Secondary (CH3)2CHCH2OH Primary Tertiary (CH3)3COH Substitutive name: Functional class names: CH3CH2CH2CH2OH 1-Butanol n-Butyl alcohol or butyl alcohol 2-Methyl-1-propanol Isobutyl alcohol or 2-methylpropyl alcohol (CH3)2CHCH2OH CH3CHCH2CH3 OH 2-Butanol sec-Butyl alcohol or 1-methylpropyl alcohol 2-Methyl-2-propanol tert-Butyl alcohol or 1,1-dimethylethyl alcohol (CH3)3COH
APPENDIX 2 A-15 CH3CH?CH CHa CH, CH, CH, Br +:O 2-Butanol Rate-determining step is unimolecular, therefore, SNI 1. CH3 CH_ CHCH3+H- ≥CH3CH2CHCH3+:Br: 2. CH3 CH;CHCH3 CH3CH, CHCH3+ O 3CH2 CHCH3-CH3, CHCH3 4.15(CH3),CCH,CH3 4.16(b)The carbon-earbon bond dissociation is lower for 2-methylpropane because it yields a more stable dary) radical; propane a primary radical. (c) The carbon-earbon bond dissociation energy is lower for 2, 2-dimethylpropane because it yields a still more stable ter tiary radical 4.17 Initiation: Cl-Cl:->: CI.+.Cl: Chlorine 2 Chlorine atoms H H Chloromethane Chlorine atom Chloromethyl radical Hydrogen chloride aqi:→→cl-c-(:+ Chloromethyl radical Chlorine Dichloromethane Chlorine atom 4.18 CH3, and CICH2CH-CI 4.19 1-Chloropropane(43%); 2-chloropropane (57%) 4.20(b) C(CH3)2 (c) CH3 Forward Main Menu TOC Study Guide Toc Student OLCMHHE Website
APPENDIX 2 A-15 2. 2-Butanol: Rate-determining step is unimolecular, therefore, SN1. 1. 2. 3. 4.15 4.16 (b) The carbon—carbon bond dissociation energy is lower for 2-methylpropane because it yields a more stable (secondary) radical; propane yields a primary radical. (c) The carbon—carbon bond dissociation energy is lower for 2,2-dimethylpropane because it yields a still more stable tertiary radical. 4.17 Initiation: Propagation: 4.18 CH3CHCl2 and ClCH2CH2Cl 4.19 1-Chloropropane (43%); 2-chloropropane (57%) 4.20 (b) (c) Br C(CH3)2 CH3 Br Cl C Cl H H Dichloromethane Cl Cl Chlorine Cl C H H Chloromethyl radical Chlorine atom Cl Cl Chlorine atom Cl C H H H Chloromethane Cl C H H Chloromethyl radical H Cl Hydrogen chloride Cl Cl Chlorine Cl Cl 2 Chlorine atoms (CH3)2CCH2CH3 Br CHCH3 CH3CH2 Br CH3CH2CHCH3 fast O CH3CH2CHCH3 H H CH3CH2CHCH3 slow O H H O CH3CH2CHCH3 H fast H Br Br O CH3CH2CHCH3 H H CH2 CH3CH2CH2 Br H O H slow CH3CH2CH2CH2Br H O H