Organic Practice

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Chapter 1 
 1
MULTIPLE CHOICE QUESTIONS 
 
Topic: Atomic Orbitals 
 
1. In quantum mechanics a node (nodal surface or plane) is: 
A) a place where Ψ is negative. 
B) a place where Ψ is positive. 
C) a place where Ψ = 0. 
D) a place where Ψ2 is large. 
E) a place where Ψ2 is negative. 
Ans: C 
 
Topic: Atomic Orbitals, Molecular Orbitals 
 
2. When the 1s orbitals of two hydrogen atoms combine to form a hydrogen molecule, 
how many molecular orbitals are formed? 
A) 1 
B) 2 
C) 3 
D) 4 
E) 5 
Ans: B 
 
Topic: Atomic Orbitals 
 
3. Which principle(s) or rule must be used to determine the correct electronic configuration 
for carbon in its ground state? 
A) Aufbau Principle 
B) Hund's Rule 
C) Pauli Exclusion Principle 
D) (A) and (B) only 
E) All three 
Ans: E 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 1 
 2
Topic: Atomic Orbitals, Bonding 
 
4. What point on the potential energy diagram below represents the most stable state for 
the hydrogen molecule? 
 
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: C 
 
Topic: Atomic Orbitals, Molecular Orbitals 
 
5. According to molecular orbital theory, which molecule could not exist? 
A) H2 
B) He2 
C) Li2 
D) F2 
E) N2 
Ans: B 
 
Topic: Atomic Orbitals, Molecular Orbitals 
 
6. When the ls orbitals of two hydrogen atoms combine to form a hydrogen molecule, 
which molecular orbitals are formed? 
A) One bonding molecular orbital only 
B) Two bonding molecular orbitals 
C) One bonding molecular orbital and one antibonding molecular orbital 
D) Two antibonding molecular orbitals 
E) Three bonding molecular orbitals 
Ans: C 
 
 
 
 
 
 
 
Chapter 1 
 3
Topic: Atomic Orbitals, Hybridization 
 
7. The following electron configuration represents _______. 
1s 2sp32sp32sp32sp3
A) the ground state of boron. 
B) the sp3 hybridized state of carbon. 
C) the sp3 hybridized state of nitrogen. 
D) the ground state of carbon. 
E) an excited state of carbon. 
Ans: C 
 
Topic: Atomic Orbitals, Molecular Orbitals 
 
8. According to molecular orbital theory, in the case of a carbon-carbon double bond, the 
carbon-carbon bonding electrons of higher energy occupy this molecular orbital. 
A) σ bonding MO 
B) π bonding MO 
C) σ* antibonding MO 
D) π* antibonding MO 
E) π* bonding MO 
Ans: B 
 
Topic: Atomic Orbitals, Hybridization 
 
9. Identify the atomic orbitals in the C-C sigma bond in ethyne. 
A) (2sp2, 2sp2) 
B) (2sp3, 2sp3) 
C) (2sp, 2sp) 
D) (2p, 2p) 
E) (2sp, 1s) 
Ans: C 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 1 
 4
Topic: Lewis Structures, Formal Charges 
 
10. Listed below are electron dot formulas for several simple molecules and ions. All 
valence electrons are shown; however, electrical charges have been omitted deliberately.
 
H H H H
HH
I II III IV V
H : Be : H H : B : H H : N : H H : N : H H : O : H
. .. .. .. .
. . . . . . . .
 
 
Which of the structures actually bear(s) a positive charge? 
A) I 
B) II 
C) III 
D) III & V 
E) IV & V 
Ans: E 
 
Topic: Lewis Structures, Formal Charges 
 
11. What is the formal charge on oxygen in the following structure? 
OH3C CH3
CH3
. .
 
 
A) +2 
B) +1 
C) 0 
D) -1 
E) -2 
Ans: B 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 1 
 5
Topic: Lewis Structures, Formal Charges 
 
12. In which structure(s) below does the oxygen have a formal charge of +1? 
 
OC HHOHOH H
H
OH3C CH3
CH3
II III IVI
. .. .. .. .
:. .
H
 
 s 
A) I only 
B) II only 
C) I and III 
D) I and IV 
E) I, III, and IV 
Ans: E 
 
Topic: Lewis Structures, Formal Charges 
 
13. Which structure(s) contain(s) an oxygen that bears a formal charge of +1? 
OH3C CH3
CH3
IV
OH3C H
H
III
OCO
II
O
CH
O
I
O
C
O
O
V
. .. .. .::
. .
. .
. .
::
:
. .
. .
::
:
. . ::
 
 
A) I and II 
B) III and IV 
C) V 
D) II 
E) I and V 
Ans: B 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 1 
 6
Topic: Lewis Structures, Formal Charges 
 
14. Which of the following molecules or ions has a nitrogen with a formal charge of -1? 
(Charges on ions have been omitted.) 
A) N H
H
. .
:
 
B) NH H
H
. .
 
C) NH CH3
H
. .
 
D) NH3C CH3
H
. .
 
E) CH3C N:
Ans: A 
 
Topic: Lewis Structures, Formal Charges 
 
15. In which structure(s) below does nitrogen have a formal charge of +1? 
NH3C CH3
CH3
NH3C CH2
H
NH3C H NH2H3C
IVIIIIII V
N
H
OH
H
. .. . . .
. .
. . . .
. .
 
A) I 
B) II and IV 
C) III and V 
D) I and V 
E) V 
Ans: A 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 1 
 7
Topic: Lewis Structures, Formal Charges 
 
16. Which of the following is an ion with a single negative charge? 
A) OH3C
. .
:. . 
B) ONO
. .
::
. .
. .
. .
 
C) 
O
NO
O
. .
. .
::
: :
:
. .
 
D) All of these 
E) None of these 
Ans: D 
 
Topic: Lewis Structures, Formal Charges 
 
17. Which of these is a correct electron-dot representation of the nitrite ion, NO2-? 
IV
IIIIII
V
: O : N : : O : O : : N : O : : O : : N : : O
: O : N : O : : O : : N : O
. .
. .
. . . .
. .
. .
. . . .
. . . .
. .
. .
. .
. .
. . . .
. .. . . . . . . .
. .. .
 
 
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: A 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 1 
 8
Topic: Lewis Structures, Formal Charges 
 
18. Which is NOT a correct Lewis structure? 
A) NH F
H
. .
. . :
 
B) 
CH F
H
H
:
..
..
 
C) OH O
. .
. . H
. .
. . 
D) 
O
BO
O
. .
. .
:
:. .
. .H
H
H 
E) None of these 
Ans: A 
 
Topic: Lewis Structures, Formal Charges 
 
19. Listed below are electron dot formulas for several simple molecules and ions. All 
valence electrons are shown; however, electrical charges have been omitted deliberately.
 
H H H H
HH
I IV VII III
H : Be : H H : B : H H : N : H H : N : H H : O : H
. .. .. .. .
. . . . . . . .
 
 
 
Which of the structures is negatively charged? 
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: B 
 
 
 
 
 
 
 
 
 
Chapter 1 
 9
Topic: Lewis Structures, Formal Charges 
 
20. Which compound contains a nitrogen atom with a formal positive charge? 
H
N N
N
I II III 
 
A) I 
B) II 
C) III 
D) More than one of the above 
E) None of the above 
Ans: D 
 
Topic: Lewis Structures 
 
21. Considering Lewis structures, which of these compounds possesses a single unpaired 
electron? 
A) N2 
B) N2O 
C) NO 
D) N2O4 
E) O2 
Ans: C 
 
Topic: Lewis Structures 
 
22. 
 Y
Z
Y
..
.. is a generalized structural representation which can be used for all of the 
following, except: 
A) OF2 
B) NH2– 
C) H2S 
D) BeBr2 
E) There is no exception 
Ans: D 
 
 
 
 
 
 
 
Chapter 1 
 10
Topic: Lewis Structures, Formal Charges 
 
23. In which of these cases does the central atom have a zero formal charge? 
A) HFH 
B) 
OH3C CH3
H
 
C) 
BF F
F
F 
D) 
NH3C CH3
H
H 
E) 
CH3C CH3
CH3
CH3 
Ans: E 
 
Topic: Lewis Structures, Formal Charges 
 
24. The formal charge on sulfur in sulfuric acid is: 
 
SO O
O
O
H H
 
A) 0 
B) -1 
C) +1 
D) -2 
E) +2 
Ans: A 
 
Topic: Lewis Structures, Formal Charges 
 
25. ExpAns:ion of the valence shell to accommodate more than eight electrons is possible 
with: 
A) Fluorine 
B) Nitrogen 
C) Carbon 
D) Sulfur 
E) Beryllium 
Ans: D 
 
 
 
Chapter 1 
 11
Topic: Lewis Structures, Molecular Geometry26. Based on VSEPR theory, which of the following would have a trigonal planar shape? 
A) CH3)3N 
B) HCN 
C) NH4+ 
D) CH3− 
E) CH3+ 
Ans: E 
 
Topic: Lewis Structures, Molecular Geometry 
 
27. VSEPR theory predicts an identical shape for all of the following, except: 
A) NH3 
B) H3O+ 
C) BH3 
D) CH3- 
E) All have the same geometry 
Ans: C 
 
Topic: Lewis Structures, Molecular Geometry 
 
28. What shape does the methyl cation, CH3+, have? 
A) Octahedral 
B) Tetrahedral 
C) Trigonal planar 
D) Linear 
E) Trigonal pyramidal 
Ans: C 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 1 
 12
 
Topic: Lewis Structures, Molecular Geometry 
 
29. Which of the structures below would be trigonal planar (a planar triangle)? (Electrical 
charges have been deliberately omitted.) 
F
F
I II III
F
F
IV
H
H
H
B : F
. .
. . :
..
..
: .
...
: ....
H : O : H H : C : F : N :
. .
. .:
. .
. .
: .
...
: ....
..
..
..
..
 
 
A) I 
B) II 
C) III 
D) IV 
E) I and IV 
Ans: A 
 
Topic: Lewis Structures, Molecular Geometry 
 
30. Which of the following would have a trigonal planar (or triangular) structure? 
I II III IV V
: CH3 : CH3 : NH3 : OH3BH3
 
 
A) I, II, and IV 
B) II and IV 
C) IV 
D) II, IV, and V 
E) All of these 
Ans: B 
 
Topic: Molecular Geometry 
 
31. What bond angle is associated with a tetrahedral molecule? 
A) 120° 
B) 109.5° 
C) 180° 
D) 90° 
E) 45° 
Ans: B 
 
 
 
 
Chapter 1 
 13
Topic: Molecular Geometry 
 
32. What would be the spatial arrangement of the atoms of the methyl anion, :CH3-? 
A) Octahedral 
B) Tetrahedral 
C) Trigonal planar 
D) Linear 
E) Trigonal pyramidal 
Ans: E 
 
Topic: Lewis Structures, Molecular Geometry 
 
33. Which of these structures would be a perfectly regular tetrahedron? 
A) CH3Br 
B) CH2Br2 
C) CHBr3 
D) CBr4 
E) More than one of these 
Ans: D 
 
Topic: Lewis Structures, Molecular Geometry 
 
34. Which molecule would be linear? (In each case you should write a Lewis structure 
before deciding.) 
A) SO2 
B) HCN 
C) H2O2 
D) H2S 
E) OF2 
Ans: B 
 
Topic: Lewis Structures, Molecular Geometry 
 
35. The bond angles in PH3 would be expected to be approximately: 
A) 60° 
B) 90° 
C) 105° 
D) 109° 
E) 120° 
Ans: C 
 
 
 
 
 
 
Chapter 1 
 14
Topic: Periodic Properties, Electronegativity 
 
36. Select the most electronegative element. 
A) H 
B) O 
C) N 
D) B 
E) C 
Ans: N 
 
Topic: Atomic Orbitals, Hybridization 
 
37. Select the hybridized atomic orbital. 
I II III IV V 
 
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: C 
 
Topic: Atomic Orbitals, Hybridization 
 
38. How many 2p atomic orbitals from boron must be mixed with a 2s atomic orbital to 
yield the bonding hybrid atomic orbitals in BF3? 
A) 1 
B) 2 
C) 3 
D) 4 
E) 5 
Ans: B 
 
 
 
 
 
 
 
 
 
 
Chapter 1 
 15
Topic: Atomic Orbitals, Hybridization 
 
39. In which molecule is the central atom sp3 hybridized? 
A) CH4 
B) NH3 
C) H2O 
D) All of these 
E) None of these 
Ans: D 
 
Topic: Atomic Orbitals, Hybridization 
 
40. In which of the following would you expect the central atom to be sp3 hybridized (or 
approximately sp3 hybridized)? 
A) BH4- 
B) NH4+ 
C) CCl4 
D) CH3:- 
E) All of these 
Ans: D 
 
Topic: Atomic orbitals, hybridization 
 
41. Which compound has the shortest carbon-carbon bond(s)? 
A) CH3CH3 
B) CH2=CH2 
C) HC≡CH 
D) CH3CH2CH3 
E) All carbon-carbon bonds are the same length. 
Ans: C 
 
Topic: Atomic Orbitals, Hybridization 
 
42. Which of the following contains an sp2-hybridized carbon? 
A) CH4 
B) CH3:− 
C) CH3CH3 
D) CH3+ 
E) HC≡CH 
Ans: D 
 
 
 
 
 
 
Chapter 1 
 16
Topic: Atomic Orbitals, Hybridization 
 
43. Which is the shortest of the carbon-carbon single bonds indicated by arrows in the 
following compounds? 
A) 
H3C CH3 
B) 
H3C C CH 
C) 
H3C CH
CH2
 
D) 
HC C C CH 
E) H2C
HC C CH 
Ans: D 
 
Topic: Atomic Orbitals, Hybridization 
 
44. How many sigma (1s-2sp3) bonds are there in ethane? 
A) 7 
B) 6 
C) 5 
D) 3 
E) 1 
Ans: B 
 
Topic: Atomic Orbitals, Bonding 
 
45. Which of these substances contains both covalent and ionic bonds? 
A) NH4Cl 
B) H2O2 
C) CH4 
D) HCN 
E) H2S 
Ans: A 
 
 
 
 
 
 
 
 
 
Chapter 1 
 17
Topic: Atomic Orbitals, Periodic Trends, Electronegativity 
 
46. The greatest degree of ionic character is anticipated for the bond between: 
A) H and C 
B) H and Cl 
C) C and Cl 
D) H and Br 
E) Br and Cl 
Ans: B 
 
Topic: Atomic Orbitals, Hybridization 
 
47. Which molecule contains an sp-hybridized carbon? 
A) HCN 
B) CH2=CH2 
C) CH3Cl 
D) H
C O
H 
E) CH3CH3 
Ans: A 
 
Topic: Atomic Orbitals, Lewis structures, Resonance 
 
48. Which of the structures below is not expected to contribute to the CO2 resonance 
hybrid? 
A) 
O C O 
B) O C O 
C) O C O 
D) O C O 
E) 
O C O 
Ans: D 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 1 
 18
Topic: Atomic orbitals, Lewis structures, resonance 
 
49. Which of the following could not be a resonance structure of CH3NO2? 
A) 
C
H
H
H
N
O
O
: ....
..
..
 
B) 
C
H
H
H
N
O
O
: .
...
: ..
 
C) 
C
H
H
H
N
O
O
: .
...
: ....
+2
 
D) 
C
H
H
H
N
O
O
H
: ....
..
.. 
E) Both C and D 
Ans: D 
 
Topic: Atomic Orbitals, Lewis Structures, Resonance 
 
50. Which of the following pairs are NOT resonance structures? 
A) 
 
H3C O N O
: : :
: : H3C O N O
: : :
:and :
B) 
:
..
..
O C O O C Oand
: ..
:..
:..
 
 
 
C) 
H3C O N O
: : :
: : H3C N
O
O: .
...
....
and
D) Each of these pairs represents resonance structures. 
E) None of these pairs represents resonance structures. 
Ans: C 
 
 
 
 
 
 
 
Chapter 1 
 19
Topic: Atomic Orbitals, Lewis Structures, Resonance 
 
51. How many resonance structures can be written for the NO3- ion in which the nitrogen 
atom bears a formal charge of +1? 
A) 1 
B) 2 
C) 3 
D) 4 
E) 5 
Ans: C 
 
Topic: Empirical and Molecular Formulas 
 
52. What is the empirical formula for cyclohexane? (Its molecular formula is C6H12.) 
A) CH 
B) CH2 
C) C2H4 
D) C6H6 
E) C2H2 
Ans: B 
 
Topic: Empirical and Molecular Formulas 
53. A compound has the empirical formula, CCl. Its molecular weight is 285 +/- 5. What is 
the molecular formula for the compound? 
A) C2Cl2 
B) C3Cl3 
C) C4Cl4 
D) C5Cl5 
E) C6Cl6 
Ans: E 
 
Topic: Empirical and Molecular Formulas 
 
54. A compound consists only of carbon, hydrogen and oxygen. Elemental analysis gave: 
C, 70.5%, H, 13.8%. The molecular weight of the compound was found to be 103 +/- 3. 
What is the molecular formula for the compound? 
A) C6H12O 
B) C5H12O2 
C) C3H2O4 
D) C3H6O3 
E) C6H14O 
Ans: E 
 
 
 
 
Chapter 1 
 20
 
Topic: Isomerism 
 
55. Which of the following is a set of constitutional isomers? 
Br Br
Br
Br
IVIIIIII 
 
A) I and II 
B) II and III 
C) I, II, and III 
D) II, III, and IV 
E) I, III, and IV 
Ans: E 
 
Topic: General 
 
56. Credit for the first synthesis of an organic compound from an inorganic precursor is 
usually given to: 
A) Berzelius 
B) Arrhenius 
C) Kekule 
D) Wohler 
E) Lewis 
Ans: D 
 
Topic: Isomerism 
 
57. CH3CH2OCH2CH3 and CH3CH2CH2CH2OH are examples of what are now termed: 
A) Structural isomers 
B) Resonancestructures 
C) Functional isomers 
D) Empirical isomers 
E) Constitutional isomers 
Ans: E 
 
 
 
 
 
 
 
 
 
Chapter 1 
 21
Topic: Hybridization 
 
58. What is the approximate hybridization state of the oxygen molecule in ethanol, 
C2H5OH? 
A) sp 
B) sp2 
C) sp3 
D) p3 
E) d2sp3 
Ans: C 
 
Topic: Hybridization 
 
59. What is the approximate hybridization state of the oxygen molecule in trimethylamine, 
(CH3)3N? 
A) sp 
B) sp2 
C) sp3 
D) p3 
E) d2sp3 
Ans: C 
 
Topic: Lewis structures, Hybridization 
 
60. Which molecule has a non-linear structure (i.e., for which molecule are the nuclei not in 
a straight line)? 
A) O=C=O 
B) H–O–H 
C) H–Cl 
D) H–C≡N 
E) H–C≡C–H 
Ans: B 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 1 
 22
Topic: Isomerism 
 
61. Which of the following structures represent compounds that are constitutional isomers 
of each other? 
IIIIII IV 
 
 
A) I and II 
B) I and III 
C) I, II, and III 
D) I, II, III, and IV 
E) II and III 
Ans: C 
 
Topic: Isomerism 
 
62. Which compound is not an isomer of the others? 
O
O
IIIIII IV
OH
OH
 
 
A) I 
B) II 
C) III 
D) IV 
E) All of the above are isomers of each other. 
Ans: A 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 1 
 23
Topic: Isomerism 
 
63. Consider the following: 
 
 CH3CH2CH=CHCH2CH3 CH3CH2CH2CH2CH=CH2
I II 
 
CH3CH=CHCH2CH2CH3 CH2=CHCH2CH2CH2CH3
III IV 
 
 Which two structures represent the same compound? 
A) I and II 
B) II and III 
C) I and III 
D) II and IV 
E) None of these 
Ans: D 
 
Topic: Isomerism 
 
64. Consider the following: 
 
 CH3CH2CH2CH=CHCH2CH2CH3 CH3CH2CH2CH2CH2CH2CH=CH2 
I II 
 
CH3CH2CH=CHCH2CH2CH2CH3 CH2=CHCH2CH2CH2CH2CH2CH3 
III IV 
 
 Which structures can exist as cis-trAns: isomers? 
A) I and II 
B) I and III 
C) I and IV 
D) II and III 
E) I alone 
Ans: B 
 
 
 
 
 
 
 
 
 
 
 
Chapter 1 
 24
Topic: Isomerism 
 
65. Which of the following represent a pair of constitutional isomers? 
A) 
and 
B) CH3CH=CH2 and CH2=CHCH3 
C) 
H
Br
Br
H
Br
Br
H
H
and
D) 
Br
Br
H
H
H
Br
H
Br
and
E) More than one of these 
Ans: E 
 
Topic: Isomerism 
 
66. Which of the following represent pairs of constitutional isomers? 
A) OH
O O
O
and
B) 
H
CH3
Br
H
Br
CH3
H
H
and
C) 
Br CH3
CH2
H
Br
H
CH3
and
D) More than one of these pairs 
E) All of these pairs 
Ans: D 
 
Topic: Isomerism 
 
67. Cis-trAns: isomerism is possible only in the case of: 
A) CH2=CBr2 
B) CH2=CHBr 
C) BrCH=CHBr 
D) Br2C=CHBr 
E) Br2C=CBr2 
Ans: C 
 
 
 
Chapter 1 
 25
Topic: Atomic orbitals, molecular orbitals 
 
68. When the 1s orbitals of two hydrogen atoms combine to form a hydrogen molecule, 
how are the electrons distributed in the resulting molecular orbitals? 
A) 2 electrons in the bonding molecular orbital 
B) 1 electron in the bonding molecular orbital, 1 electron in the non-bonding molecular 
orbital 
C) 1 electron in the bonding molecular orbital, 1 electron in the antibonding molecular 
orbital 
D) 2 electrons in the non-bonding molecular orbital 
E) 2 electrons in the antibonding molecular orbital 
Ans: A 
 
Topic: Atomic Orbitals, Electron Configuration, Hybridization 
 
69. The following electron configuration represents: 
1s 2sp32sp32sp32sp3
A) The ground state of nitrogen 
B) The ground state of oxygen 
C) The sp3 hybridized state of carbon 
D) The excited state of oxygen 
E) None of the above correctly identifies the given electron configuration 
Ans: E 
 
Topic: Atomic Orbitals, Hybridization, Bonding 
 
70. Identify the atomic orbitals involved in the C-2---C-3 sigma bond (indicated by an 
arrow) in the following molecule: 
1
2
3
4
5
6
7
A) sp2, sp2 
B) sp2, sp 
C) sp2, sp3 
D) sp3, sp2 
E) sp, sp2 
Ans: E 
 
 
 
 
 
 
Chapter 1 
 26
Topic: Lewis Structures 
 
71. In which of the following does the central atom have 2 pairs of non-bonding electrons? 
A) O3 
B) CO2 
C) CO3 2− 
D) NH4+ 
E) H2S 
Ans: E 
 
Topic: Molecular Geometry 
 
72. Based on the VSEPR theory, which of the following would have a tetrahedral 
arrangement of electrons around the central atom? 
A) BH3 
B) NO2 − 
C) SiH4 
D) CO3 2− 
E) SO3 
Ans: C 
 
Topic: Molecular Geometry 
 
73. What would be the spatial arrangement of the atoms of the ozone molecule (O3)? 
A) Linear 
B) Angular 
C) Trigonal planar 
D) Trigonal pyramidal 
E) Tetrahedral 
Ans: B 
 
Topic: Periodic Trends, Electronegativity 
 
74. Select the least electronegative element 
A) P 
B) N 
C) Mg 
D) Si 
E) K 
Ans: E 
 
 
 
 
 
 
Chapter 1 
 27
Topic: Atomic Orbitals, Hybridization 
 
75. In which molecule(s) can the molecular geometry be attributed to an sp2 hybridized 
central atom? 
A) PBr3 
B) CH4 
C) CHCl3 
D) HNO2 
E) None of the above has an sp2 hybridized central atom 
Ans: D 
 
Topic: Bonding, Atomic Orbitals, Hybridization 
 
76. Which molecule has the shortest carbon-carbon single bond? 
I II III
IV V 
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: E 
 
Topic: Atomic Orbitals, Hybridization 
 
 77. How many s-sp2 bonds are there in the following substance? 
 
A) 2 
B) 3 
C) 4 
D) 5 
E) 12 
Ans: B 
 
 
 
Chapter 1 
 28
Topic: Atomic Orbitals, Hybridization 
 
78. How many s-sp3 bonds are there in the following substance? 
 
A) 3 
B) 8 
C) 12 
D) 13 
E) 16 
Ans: D 
 
Topic: Resonance 
 
79. Which of the following species exhibits resonance stabilization? 
A) H2SO4 
B) O3 
C) CO2 
D) CCl4 
E) None of the above species exhibit resonance 
Ans: B 
 
 
SHORT ANS:WER QUESTIONS 
 
Topic: General 
 
80. Organic compounds were originally defined as compounds obtained from __________. 
Ans: living sources/organisms 
 
Topic: General 
 
81. The modern definition of organic chemistry is _________________. 
Ans: the study of carbon compounds 
 
Topic: General 
 
82. Different compounds with the same molecular formula are referred to as __________. 
Ans: isomers 
 
 
 
 
 
Chapter 1 
 29
Topic: General 
 
83. Constitutional isomers differ in the _________________. 
Ans: connectivity of their atoms 
 
Topic: General 
 
84. The bond that results when two atoms share a pair of electrons is called a 
_________________. 
Ans: covalent bond 
 
Topic: Atomic orbitals 
 
85. Define an orbital. 
Ans: a region of space where the probability of finding an electron is high 
 
Topic: Atomic orbitals 
 
86. 
 
An orbital is defined as a region of space where the probability of _________________ 
is high. 
Ans: finding an electron 
 
Topic: Atomic orbitals 
 
87. 
 
There are three fundamental rules that we use in writing electronic configurations for 
atoms and molecules. The configuration shown below (for oxygen) violates one of these 
rules. Which one? 
 1s 2p2p2p2s
Ans: Pauli exclusion principle 
 
Topic: Molecular orbitals 
 
88. 
 
When atomic orbitals of opposite phase overlap a(n) _________________ molecular 
orbital is formed. 
Ans: antibonding 
 
Topic: Molecular orbitals 
 
89. 
 
When atomic orbitals of the same phase overlap a(n) _________________ molecular 
orbital is formed. 
Ans: bonding 
 
 
 
Chapter 1 
 30
Topic: Lewis Structures 
 
90. 
 
Draw the Lewis structure of the nitrite ion, NO2− , clearly indicating resonance 
contributors as well as non-bonding pairs of electrons and formal charges, as relevant. 
Ans: 
..
..
N
O
O
..
. .
. .
..
.
.
.
.
N
O
O
..
.
.
.
.
.
.
 
Topic: Isomers, Bond-Line Formulas 
 
91. Draw all the isomers of C4H9Br, using bond-line formulas. 
Ans: 
Br
Br
Br
Br
 
Topic: Isomers, Bond-Line Formulas 
 
92. Draw all the isomers of C4H10O, using bond-line formulas. 
Ans: 
OH
OH
O
O
OH
O
OH
 
Topic: Isomers, Bond-Line Formulas 
 
93. Draw all isomers of C4H8, using bond-line formulas. 
Ans: 
 
 
 
 
 
 
 
 
 
Chapter 1 
 31
Topic: Lewis Structures 
 
94. 
 
Draw the Lewis structure of acetic acid, CH3CO2H, clearly indicating all non-bonding 
pairs of electrons. 
Ans: 
C
C
O
H
O
H
H
H
. .
.. ..
. .
 
 
 
Chapter 2 
 32
MULTIPLE CHOICE QUESTIONS 
 
Topic: Intermolecular forces 
 
1. Which compound would you expect to have the lowest boiling point? 
A) NH2
 
B) NH2
 
C) 
N
H
 
D) 
N
 
E) 
NH2 
Ans:
: 
D 
 
Topic: Molecular geometry, dipole moment 
 
2. Which molecule would you expect to have no dipole moment (i.e., μ = 0 D)? 
A) CHF3 
B) 
F
H
H
F
 
C) :NF3 
D) 
H
F
H
F
 
E) CH2F2 
Ans: B 
 
 
 
 
 
 
 
 
 
 
 
Chapter 2 
 33
 
Topic: Intermolecular forces 
 
3. Which of these compounds would have the highest boiling point? 
A) CH3OCH2CH2CH2OCH3 
B) CH3CH2OCH2CH2OCH3 
C) CH3CH2OCH2OCH2CH3 
D) CH3OCH2CHOCH3
CH3 
E) HOCH2CH2CH2CH2CH2OH 
Ans: E 
 
Topic: Intermolecular forces 
 
4. Which of these would you expect to have the lowest boiling point? 
A) CH3CH2CH2OH 
B) CH3CHCH3
OH 
C) CH3OCH2CH3 
D) CH3CH2CH2CH2OH 
E) CH3CH2OCH2CH3 
Ans: C 
 
Topic: Intermolecular forces 
 
5. Which compound would have the highest boiling point? 
A) CH3CH2CH2CH2CH2CH3 
B) CH3CH2OCH2CH2CH3 
C) CH3CH2CH2CH2CH2OH 
D) CH3CH2OCH(CH3)2 
E) CH3OCH2CH2CH2CH3 
Ans: C 
 
Topic: Intermolecular forces 
 
6. Which of the following is not found in the following substance? 
 CH3CH2CH2CH2CH2OH 
A) Ion-ion 
B) van der Waals 
C) Dipole-dipole 
D) Resonance 
E) Hydrogen bonding 
Ans: D 
 
 
Chapter 2 
 34
Topic: Intermolecular forces 
 
7. Which compound would you expect to have the lowest boiling point? 
A) 
NH2
O
 
B) H
N
O 
C) 
N
O
 
D) 
NH2
O 
E) 
O N
H 
Ans: C 
 
Topic: Intermolecular forces 
 
8. Which compound would you expect to have the highest boiling point? 
A) CH3OCH2CH2OCH3 
B) CH3OCH2OCH2CH3 
C) HOCH2CH2CH2CH2OH 
D) CH3OCH2CH2CH2OH 
E) (CH3O)2CHCH3 
Ans: C 
 
Topic: Molecular geometry, dipole moment 
 
9. Which of the following would have no net dipole moment 
(μ = 0 D)? 
A) CBr4 
B) cis-1,2-Dibromoethene 
C) trAns:-1,2-Dibromoethene 
D) 1,1-Dibromoethene 
E) More than one of these 
Ans: E 
 
 
 
Chapter 2 
 35
Topic: Molecular geometry, dipole moment 
 
10. Which molecule has dipole moment greater than zero? 
A) 
H
F
H
F
 
B) 
H
H
F
F
 
C) 
F
H
H
F
 
D) More than one of these 
E) None of these 
Ans: D 
 
Topic: Intermolecular forces 
 
11. The strongest of attractive forces is which type? 
A) van der Waals 
B) Ion-dipole 
C) Dipole-dipole 
D) Cation-anion 
E) Hydrogen bonds 
Ans: D 
 
Topic: Intermolecular forces 
 
12. Of the following compounds, the one with the highest boiling point is: 
A) CH3CH3 
B) CH3CH2Cl 
C) CH3C=O
H 
D) CH3CH2OH 
E) CH3CH2OCH2CH3 
Ans: D 
 
 
 
 
 
 
 
 
 
Chapter 2 
 36
Topic: Intermolecular forces 
 
13. This alkane is predicted to have the highest melting point of those shown: 
A) CH3CH2CH2CH3 
B) CH3CHCH3
CH3 
C) CH3CH2CH2CH2CH3 
D) CH3CHCH2CH3
CH3 
E) 
CH3CCH3
CH3
CH3 
Ans: E 
 
Topic: Intermolecular forces 
 
14. The solid alkane CH3(CH2)18CH3 is expected to exhibit the greatest solubility in which 
of the following solvents? 
A) CCl4 
B) CH3OH 
C) H2O 
D) CH3NH2 
E) HOCH2CH2OH 
Ans: A 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 2 
 37
Topic: Intermolecular forces 
 
15. Which compound would have the lowest boiling point? 
 
O
OH
OH
OH
OH
I II III
IV V 
 
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: A 
 
Topic: Molecular geometry, Polarity 
 
16. Which molecule(s) has dipole moment equal to zero? 
A) Cl
 
 
B) ClCl
 
 
C) Cl
Cl 
 
D) Cl
Cl
Cl
 
 
E) None of these have dipole moment equal to zero 
Ans: C 
 
 
 
Chapter 2 
 38
Topic: Molecular geometry, polarity 
 
17. Which molecule has a zero dipole moment? 
A) SO2 
B) CO2 
C) CO 
D) CHCl3 
E) None of these 
Ans: B 
 
Topic: Molecular geometry, polarity 
 
18. Which molecule has a zero dipole moment? 
A) CH3Cl 
B) CH2Cl2 
C) CHCl3 
D) CCl4 
E) None of these 
Ans: D 
 
Topic: Molecular geometry, polarity 
 
19. Which molecule would have a dipole moment greater than zero? 
A) BeCl2 
B) BCl3 
C) CO2 
D) H2O 
E) CCl4 
Ans: D 
 
Topic: Molecular geometry, polarity 
 
20. For a molecule to possess a dipole moment, the following condition is necessary but not 
sufficient. 
A) Three or more atoms in the molecule 
B) Presence of one or more polar bonds 
C) A non-linear structure 
D) Presence of oxygen or fluorine 
E) Absence of a carbon-carbon double or triple bond 
Ans: B 
 
 
 
 
 
 
Chapter 2 
 39
Topic: Molecular geometry, polarity 
 
21. A non-zero dipole moment is exhibited by: 
A) SO2 
B) CO2 
C) CCl4 
D) BF3 
E) Cl
Cl
Cl
Cl 
Ans: A 
 
Topic: Intermolecular forces 
 
22. Which of these is the weakest of the intermolecular attractive forces? 
A) Ion-ion 
B) van der Waals 
C) Dipole-dipole 
D) Covalent bonding 
E) Hydrogen bonding 
Ans: B 
 
Topic: Functional groups 
 
23. Which compound listed below is a secondary alcohol? 
A) CH3CHCH2CH3
OH 
B) CH3CHCH2OH
CH3 
C) 
CH3COH
CH3
CH3 
D) CH3CH2CH2CH2OH 
E) CH3CH2CH2OCH3 
Ans: A 
 
 
 
 
 
 
 
 
Chapter 2 
 40
Topic: Functional groups 
 
24. Which compound is a secondary amine? 
A) CH3CH2CH2NH2 
B) CH3CHCH3
NH2 
C) 
CH3
CH3CH2NH
 
D) NH3C CH3
CH3 
E) CH3CH2CHNH2
CH3 
Ans: C 
 
Topic: Functional groups 
 
25. Which compound is an aldehyde? 
 
 
NH
I II III
IV V
O O
O
O
OH
O
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: D 
 
 
 
 
 
 
 
Chapter 2 
 41
Topic: Functional groups 
 
26. Which compound is a ketone? 
A) 
C
H
OH
O
 
B) 
CH3CCH2CH3
O
 
C) 
HCOCH3
O
 
D) 
C
H
H
O
 
E) 
CH
H3C
OH
H3C
 
Ans: B 
 
Topic: Functional groups 
 
27. Which compound is an ester? 
 
 
NH
O
I II III
IV V
O
O
O
O
OH
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: C 
 
 
 
 
Chapter 2 
 42
Topic: Functional groups 
 
28. The compound shown below is a synthetic estrogen. It is marketed as an oral 
contraceptive under the name Enovid. 
 O
OH
 
In addition to an alkane (actually cycloalkane) skeleton, the Enovid molecule also 
contains the following functional groups: 
A) Ether, alcohol, alkyne. 
B) Aldehyde, alkene, alkyne, alcohol. 
C) Alcohol, carboxylic acid, alkene, alkyne. 
D) Ketone, alkene, alcohol, alkyne. 
E) Amine, alkene, ether, alkyne. 
Ans: D 
 
Topic: Functional Groups 
 
29. Which is a 3° alkyl halide? 
Cl
I II III
IV V
Br
F
Br I
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: B 
 
 
 
 
 
 
Chapter 2 
 43
Topic: Functional groups 
 
30. Which is a 3° amine?H2N
I II III
IV V
NH2
NH
N
NH2O
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: D 
 
Topic: Functional groups 
 
31. Which functional group is not contained in prostaglandin E1? 
OH
O
O
HO
OHH H
H
H
 
 
 Prostaglandin E1 
A) Ketone 
B) 2° alcohol 
C) 3° alcohol 
D) Carboxylic acid 
E) Alkene 
Ans: C 
 
 
 
 
 
 
 
Chapter 2 
 44
Topic: Functional groups 
 
32. The compound below is an adrenocortical hormone called cortisone. Which functional 
group is not present in cortisone? 
O
OHO
O
OH
 
 
A) 1° alcohol 
B) 2° alcohol 
C) 3° alcohol 
D) Ketone 
E) Alkene 
Ans: B 
 
Topic: Functional groups 
 
33. The compound shown below is a substance called Capsaicin, found in varying 
concentrations in several varieties of hot peppers, and responsible for their respective 
degrees of “heat”. Which functional groups are present in the molecule of capsaicin? 
N
H
O
O
OH
Capsaicin
A) Alkene, ketone, amine, alcohol, ester 
B) Alkene, ketone, alcohol, ether 
C) Alkene, amine, phenol, ether 
D) Ether, phenol, alkene, amide 
E) Ester, phenol, alkene, amide 
Ans: D 
 
 
 
 
 
 
 
 
 
 
 
Chapter 2 
 45
 
Topic: Functional groups 
 
34. Drawn below is Atropine, found in Atropa belladonna, sometimes used in dilating 
pupils during an eye-exam. Which of the following functional groups is NOT in 
atropine? 
 
N
O
O OH
Atropine 
 
A) Amine 
B) Ester 
C) Alcohol 
D) Benzene Ring 
E) Ketone 
Ans: E 
 
Topic: Functional groups 
 
35. The compound shown below is the male sex hormone, testosterone. 
 O
OH
O
 
In addition to a cycloalkane skeleton, testosterone also contains the following functional 
groups: 
A) Alkene, ester, tertiary alcohol. 
B) Alkene, ether, secondary alcohol. 
C) Alkene, ketone, secondary alcohol. 
D) Alkyne, ketone, secondary alcohol. 
E) Alkene, ketone, tertiary alcohol. 
Ans: C 
 
 
 
 
 
 
 
 
 
Chapter 2 
 46
Topic: Functional groups 
 
36. Which is a carboxylic acid? 
O
O
OH
OH
I II III
IV V
OH
O O
O
O
O
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: E 
 
Topic: Functional groups 
 
37. Which compound is a tertiary alcohol? 
 
 
H3CH2C HO
CH3
CH3
HO
O
OH
I II III
IV V
OH
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: E 
 
 
 
Chapter 2 
 47
Topic: Functional groups 
 
38. Which compound is a primary amine with the formula C5H13N? 
 
H2N
N
H2N
I II III
IV V
NH2
NH
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: C 
 
Topic: Functional groups 
 
39. Which compound can be classified as an ester as well as a ketone? 
O
O O
O
O
O O
O
O
OH
O
I II III
IV V
OH
O
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: D 
 
 
 
 
 
 
 
 
Chapter 2 
 48
Topic: Functional groups 
 
40. The C–O–C bond angle in diethyl ether is predicted to be approximately: 
A) 90º 
B) 105º 
C) 110º 
D) 120º 
E) 180º 
Ans: C 
 
Topic: Functional groups 
 
41. Which compound(s) contain(s) tertiary carbon atom(s)? 
F
Br
OH
OH
I II III
IV V
A) I, II, III 
B) I 
C) II, III 
D) I, IV 
E) V 
Ans: D 
 
Topic: Isomers 
 
42. The number of unique open-chain structures corresponding to the molecular formula 
C3H5Cl is: 
A) 2 
B) 3 
C) 4 
D) 5 
E) 6 
Ans: C 
 
 
 
 
 
 
 
 
Chapter 2 
 49
Topic: General, Bonding 
 
43. The C4-C5 carbon-carbon bond in the following molecule results from the overlap of 
which orbitals ( in the order C4-C5) ? 
 
1
2
3
4
5
6
7
o
A) sp–sp2 
B) sp–sp3 
C) sp2–sp2 
D) sp2–sp3 
E) sp3–sp2 
Ans: E 
 
Topic: Functional groups 
 
44. An example of a tertiary amine is: 
NH2 H2N
NH2
H
N
N
I II III
IV V 
 
 
 
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: E 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 2 
 50
Topic: Functional groups 
 
45. Which functional groups are present in the following compound? 
 
A) Alkene, 1º alcohol, ketone 
B) Alkene, 2º alcohol, aldehyde 
C) Alkene, 2º alcohol, ketone 
D) Alkyne, 1º alcohol, aldehyde 
E) Alkyne, 2º alcohol, ketone 
Ans: B 
 
Topic: Functional groups, Isomerism 
 
46. How many constitutional isomers are possible with the formula C4H10O? 
A) 3 
B) 4 
C) 5 
D) 6 
E) 7 
Ans: E 
 
Topic: Functional groups 
 
47. A tertiary carbon atom is present in which of these compounds? 
OH
HO
ClCl
I II III
IV V
A) I 
B) II, IV 
C) III, V 
D) IV 
E) All of these 
Ans: C 
 
 
 
 
 
 
 
Chapter 2 
 51
Topic: Functional groups 
 
48. Which of these compounds is a secondary alkyl chloride? 
A) CH3CH2CH2CH2CH2Cl 
B) 
CH3CCH2CH3
CH3
Cl 
C) CH3CHCH2CH2CH3
Cl 
D) CH3CH2CHCl
CH2CH3 
E) Two of these 
Ans: E 
 
Topic: Functional groups, Isomerism 
 
49. How many 2º alkyl bromides, neglecting stereoisomers, exist with the formula C6H13Br?
A) 4 
B) 5 
C) 6 
D) 7 
E) 8 
Ans: C 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 2 
 52
Topic: Functional Groups 
 
50. Many organic compounds contain more than one functional group. Which of the 
following is both an aldehyde and an ether? 
O
O
O
O
O O
O
O
OCH3
O
O
I II III
IV V
A) I, 
B) II, IV 
C) V 
D) I, V 
E) III 
Ans: A 
 
Topic: IR Spectroscopy 
 
51. An oxygen-containing compound shows strong IR absorption at 1630-1780 cm-1 and 
3200-3550 cm-1. What type of compound is it likely to be? 
A) An alcohol 
B) A carboxylic acid 
C) An ether 
D) A ketone 
E) An aldehyde 
Ans: B 
 
Topic: IR Spectroscopy 
 
52. The absorption band for the O-H stretch in the IR spectrum of an alcohol is sharp and 
narrow in the case of: 
A) a Nujol mull of the alcohol. 
B) a concentrated solution of the alcohol. 
C) a gas phase spectrum of the alcohol. 
D) the spectrum of the neat liquid 
E) none of these 
Ans: C 
 
 
 
 
 
 
Chapter 2 
 53
Topic: IR Spectroscopy 
 
53. A split peak for the IR absorption due to bond stretching is observed for the carbonyl 
group in which of these compounds? 
A) 
CH3CH2CH2COH
O
ca 
B) 
CH3CH2CCl
O
 
C) 
CH3CH2CNH2
O
 
D) 
CH3CH2COCH2CH3
O
 
E) 
CH3CH2COCCH2CH3
O O
 
Ans: E 
 
Topic: IR Spectroscopy 
 
54. The IR stretching frequency occurs at the lowest frequency for which of these bonds? 
A) C–H 
B) C–O 
C) C–Br 
D) C–N 
E) C–F 
Ans: C 
 
Topic: IR Spectroscopy 
 
55. The IR stretching frequency can be expected to occur at the lowest frequency for which 
of these bonds? 
A) C–H 
B) O–H 
C) N–H 
D) S–H 
E) Difficult to predict 
Ans: D 
 
 
 
 
 
 
 
 
Chapter 2 
 54
Topic: IR Spectroscopy 
 
56. The IR stretching frequency can be predicted to occur at the highest frequency for which 
of these bonds? 
A) C–H 
B) C–F 
C) C–Cl 
D) C–Br 
E) C–I 
Ans: A 
 
Topic: IR Spectroscopy 
 
57. An anticipated IR absorption band may not be observed because: 
A) it occurs outside the range of the instrument used. 
B) no change occurs in the dipole moment during the vibration. 
C) the absorption band is eclipsed by another. 
D) the intensity is so weak that it cannot be differentiated from instrument noise. 
E) All of these 
Ans: E 
 
Topic: IR Spectroscopy 
 
 58. IR evidence for the presence of the C=C would be most difficult to detect in the case of 
which of these alkenes? 
A) 
B) 
C) 
 
D) 
 
E) 
 
Ans: D 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 2 
 55
Topic: IRSpectroscopy 
 
59. 
 
The IR absorption due to the stretching of which of these carbon-hydrogen bonds occurs 
at the highest frequency? 
I II III
IV V
H
H H
H H
 
 
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: E 
 
Topic: IR Spectroscopy 
 
60. 
 
The IR spectrum of which type of compound will not show evidence of hydrogen 
bonding? 
A) Aldehyde 
B) Alcohol 
C) Carboxylic acid 
D) Phenol 
E) Primary amine 
Ans: A 
 
Topic: IR Spectroscopy 
 
61. 
 
The IR spectrum of which type of compound generally exhibits evidence of hydrogen 
bonding? 
A) Aldehyde 
B) Carboxylic acid 
C) Alkene 
D) Ester 
E) Ketone 
Ans: B 
 
 
 
 
 
 
Chapter 2 
 56
Topic: Intermolecular forces 
 
62. 
 
The following substance is expected to have low solubility in which of the following 
solvent(s)? 
 
O Na
O
A) CCl4 
B) C2H5OH 
C) CHCl3 
D) CH2OHCH2CH2CH2CH2CH2OH 
E) The given substance is likely to be quite soluble in all of the solvents described 
Ans: A 
 
Topic: IR Spectroscopy 
 
63. The IR stretching frequency occurs at the lowest frequency for which of these bonds? 
A) B–H 
B) O-H 
C) N-H 
D) S-H 
E) Difficult to predict 
Ans: D 
 
Topic: IR Spectroscopy 
 
64. 
 
An oxygen-containing compound which shows sharp IR absorption at 2200 cm-1 and 
3300 cm-1 is likely to be what type of compound? 
A) An ester 
B) An alkene 
C) An alkyne 
D) An ether 
E) An aldehyde 
Ans: B 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 2 
 57
Topic: IR Spectroscopy 
 
65. 
 
The IR spectrum of which of the following substances is likely to show a small, but 
sharp peak at 2200 cm-1? 
OH
N
H
O
I II III
IV V
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: E 
 
 
SHORT ANSWER QUESTIONS 
 
Topic: Functional Groups 
 
66. 
 
Hydrocarbons containing carbon-carbon double bonds are referred to as ___________. 
Ans: alkenes 
 
Topic: Functional Groups, IR Spectroscopy 
 
67. 
 
An IR spectrum has significant peaks at 2200 and 3300 cm-1. What functional group is 
present in the molecule? 
Ans: A terminal alkyne 
 
Topic: Functional Groups 
 
68. 
 
A group in which a carbon atom has a double bond to an oxygen atom is called a 
__________. 
Ans: carbonyl 
 
 
 
 
 
 
 
Chapter 2 
 58
 
Topic: Functional Groups, IR Spectroscopy 
 
69. 
 
An IR spectrum has significant peaks at 3080 and 1650 cm-1. What functional group is 
present in the molecule? 
 
 
 
 
Ans: an alkene 
 
 
Topic: Functional Groups, IR Spectroscopy 
 
70. Examine the following IR spectrum, for substance P (C8H22O). Which oxygen 
containing functional group is present in P? 
 
 
 
Ans: aldehyde 
 
Topic: Functional Groups, IR Spectroscopy 
 
Chapter 2 
 59
71. 
 
Examine the following IR spectrum, for substance P (C5H12O). Which oxygen 
containing functional group is present in P? 
Ans: alcohol 
 
Topic: General 
 
72. The six p-electrons in benzene are _____________ about the ring, which explains why 
all of the C-C bonds are the same length. 
Ans: delocalized 
 
Topic: General 
 
73. A polar covalent bond is one in which electrons are _____________. 
Ans: not shared equally 
 
Topic: Functional Groups 
 
74. 
 
Organic compounds are classified into chemical families on the basis of similarities in 
chemical properties; these similarities are primarily due to the presence of characteristic 
arrangements of atoms known as ________________. 
Ans: functional groups 
 
Topic: Functional Groups 
 
75. 
 
Unsaturated hydrocarbons may be distinguished from saturated hydrocarbons by the 
presence of one or more _____________. 
Ans: Pi bonds 
 
Topic: Bonding, Solubility 
 
76. Sodium chloride, which is quite soluble in water, is not very soluble in hexane. Why? 
Ans: Sodium chloride, which is an ionic substance, is soluble in a polar solvent such as 
water, but not in a non-polar solvent such as hexane. 
 
Topic: Isomers, Functional Groups 
 
77. Draw all tertiary amine isomers of C6H15N. 
Ans: 
NN
N N N
N
 
 
 
Chapter 2 
 60
Topic: Isomers, Functional Groups 
 
78. Draw all isomers of C6H14. 
Ans: 
 
 
Topic: Isomers, Functional Groups 
 
79. Draw a structural formula for C8H18 , in which there are two quaternary carbons. 
Ans: 
 
 
Topic: Isomers, Functional Groups 
 
80. Draw all isomers of C5H10O that are ketones. 
Ans: O O O
 
Topic: Isomers, Functional Groups 
 
81. Draw all isomers of C3H8O and classify each according to functional group 
Ans: 
C3H8O OH
OH
O
primary alcohol secondary alcohol ether 
 
Topic: Isomers, Functional Groups 
 
82. Draw all isomers of C6H12O that are aldehydes. 
Ans: 
O O OO
O OO
 
 
Topic: Isomers, Functional Groups 
 
83. Draw all isomers of C6H12O that are aldehydes and contain at least one tertiary carbon 
Ans: 
O OOO
 
 
Chapter 2 
 61
Topic: IR Spectroscopy 
 
84. 
 
The IR absorption frequencies of the C-H bond in alkanes, alkenes and alkynes are 
measurably different. Briefly explain why. 
Ans: IR absorption frequency depends on bond strength; the bond strength of C-H 
bonds in alkanes, alkenes and alkynes is different because different atomic 
orbitals (hybridized) of carbon are involved in the bond: the C-H bond in alkanes 
is described as (sp3-s), that in alkenes is (sp2-s) and in alkynes, it is (sp-s). The 
relative % s v. % p character of the hybrid orbitals of carbon would indicate 
different bond lengths /bond strengths for alkanes, alkenes and alkynes, with the 
bond length / bond strength being the longest/weakest respectively. This results 
in different IR absorption frequencies. 
 
Topic: Molecular Geometry, Dipole Moment 
 
85. 
 
Carbon dioxide is non- polar, despite the fact that oxygen is much more electronegative 
than carbon. Briefly explain why, using relevant diagrams as appropriate to illustrate 
your Ans:wer. 
Ans: The overall dipole moment of a polyatomic molecule depends on two factors: the 
polarity of various bonds and molecular geometry, since dipole forces have both 
magnitude and direction. In some molecules containing bonds of identical 
polarity, the molecular geometry may result in a net cancellation of the overall 
dipole forces. This is what happens in carbon dioxide: although there are two 
polar C-O bonds, because of the linear geometry of the molecule, the net dipole is 
zero. 
 OCO
. .::
. .
 
Topic: Intermolecular Forces 
 
86. Ethanol, C2H5OH, and propane, C3H8, have approximately the same molar mass, yet, 
ethanol has a much higher boiling point. Briefly explain why. 
Ans: Strong hydrogen bonding between molecules of ethanol leads to elevation in 
boiling point. No hydrogen bonding is possible between molecules of propane, 
resulting in a lower boiling point compared with ethanol. 
 
Topic: Intermolecular Forces 
 
87. Ethanol, C2H5OH, and dimethyl ether, CH3OCH3, have the same molar mass, yet, 
ethanol has a much higher boiling point. Briefly explain why. 
Ans: Strong hydrogen bonding between molecules of ethanol leads to elevation in 
boiling point. No hydrogen bonding is possible between molecules of dimethyl 
ether, resulting in a lower boiling point compared with ethanol. 
 
 
 
 
Chapter 2 
 62
Topic: IR Spectroscopy 
 
88. IR absorption signals of alcohols are typically broad. However, IR spectra of gaseous 
samples show sharp peaks. Briefly explain why. 
Ans: Broad signals of alcohols are due to hydrogen bonding associated with the O-H 
group. In gaseous samples, no hydrogen bonding is possible, and the signal 
becomes sharp.Chapter 3 
 
 63
MULTIPLE CHOICE QUESTIONS 
 
Topic: Acid-Base Definitions 
 
1. According to the Lewis definition, a base is a(n): 
A) Proton donor. 
B) Electron pair donor. 
C) Hydroxide ion donor. 
 D) Hydrogen ion donor. 
 E) Electron pair acceptor. 
 Ans: B 
 
Topic: Acid-Base Definitions 
 
2. Which of the following is not both a Bronsted-Lowry acid and a Bronsted-Lowry base? 
 A) HSO4− 
B) H2PO4− 
C) HCO3− 
D) OH− 
E) SH− 
 Ans: D 
 
Topic: Acid-Base Definitions 
 
3. Which of the following is not a conjugate acid - conjugate base pair (in that order)? 
A) H3PO4, H2PO4− 
B) HBF4, BF4− 
C) CH3CH2OH, CH3CH2O− 
D) H3O+, H2O 
E) HPO4−, H2PO4− 
 Ans: E 
 
Topic: Acid-Base Definitions 
 
4. The conjugate base of sulfuric acid is: 
 A) H3SO4+ 
B) SO3 
C) HSO4− 
D) H2SO3 
E) HSO3− 
 Ans: C 
 
 
Chapter 3 
 
 64
Topic: Acid-Base Definitions 
 
5. Consider the equilibrium 
 
PO43− + H2O ⇄ ΗPΟ42− + ΟΗ− 
 
Which are the Bronsted-Lowry bases? 
A) PO43− and HPO42− 
B) PO43− and OH− 
C) PO43− and H2O 
 D) H2O and OH− 
 E) H2O and HPO42− 
 Ans: B 
 
Topic: Acid-Base Definitions 
 
6. Which of these is not a true statement? 
A) All Lewis bases are also Bronsted-Lowry bases. 
B) All Lewis acids contain hydrogen. 
C) All Bronsted-Lowry acids contain hydrogen. 
D) All Lewis acids are electron deficient. 
E) According to the Bronsted-Lowry theory, water is both an acid and a base. 
 Ans: B 
 
Topic: Acid-Base Definitions 
 
7. For the equilibrium 
CH3NH3+ + H2O ⇄ CH3NH3+ + H3O+ 
 
the two substances which both are acids are: 
A) H2O and H3O+ 
B) CH3NH3+ and H2O 
C) CH3NH3+ and CH3NH2 
 D) CH3NH3+ and H3O+ 
 E) CH3NH2 and H2O 
 Ans: D 
 
 
 
 
 
 
 
Chapter 3 
 
 65
Topic: Acid-Base Definitions 
 
8. Which of the following is not a Lewis base? 
 A) NH3 
B) H− 
C) BF3 
D) H2O 
E) H3C− 
 Ans: C 
 
Topic: Acid-Base Definitions 
 
9. Which of the following is not a Bronsted-Lowry acid? 
 A) H2O 
B) (CH3)3N 
C) NH4+ 
D) CH3CO2H 
E) HC≡CH 
 Ans: E 
 
Topic: Acid-Base Definitions 
 
10. The reaction between which combination of substances below cannot be classified as a 
Bronsted-Lowry acid-base reaction? 
A) CH3Li + C2H5OH 
B) H2SO4 + CH3CO2Na 
C) BF3 + NH3 
D) H3O+ + CH3NH- 
E) two of the above 
 Ans: C 
 
Topic: Acid-Base Definitions 
 
11. Which of these is not a Lewis acid? 
A) AlCl3 
B) H3O+ 
C) FeCl3 
D) SO3 
E) C4H10 
 Ans: E 
 
 
 
 
Chapter 3 
 
 66
Topic: Acid-Base Definitions 
 
12. This species is a carbon-based Lewis acid: 
 A) CH4 
B) HCCl3 
C) CH3+ 
D) :CH3− 
E) ·CH3 
 Ans: C 
 
Topic: Acid-Base Definitions 
 
13. What is the conjugate base of ethanol? 
 A) CH3CH2O− 
B) CH3CH2− 
C) CH3CH2OH2+ 
D) CH3CH3 
E) CH3OCH3 
 Ans: A 
 
Topic: Acid-Base Strength 
 
14. Which of the acids below would have the strongest conjugate base? 
A) CH3CH2OH pKa = 18 
B) CH3CO2H pKa = 4.75 
C) ClCH2CO2H pKa = 2.81 
D) Cl2CHCO2H pKa = 1.29 
E) Cl3CCO2H pKa = 0.66 
 Ans: A 
 
Topic: Acid-Base Definitions 
 
15. Which of the following is a Lewis acid? 
 A) H3O+ 
B) BF3 
C) NF3 
D) OH− 
E) N≡N 
 Ans: B 
 
 
 
 
 
Chapter 3 
 
 67
Topic: Acid-Base Reactions 
 
16. Adding sodium hydride to ethanol would produce: 
A) CH3CH2OCH2CH3 + H2 D) CH3CH2Na + NaOH 
B) CH3CH2OCH2CH3 + NaOH E) CH3CH3 + NaOH 
C) CH3CH2ONa + H2 
 D)CH3CH2Na + NaOH 
 E) CH3CH3 + NaOH 
 Ans: C 
 
Topic: Acid-Base Reactions 
 
17. Adding sodium amide (NaNH2) to 1-butyne (CH3CH2C≡CH) would produce: 
A) CH3CH2C≡CNa + NH3 
B) CH3CH2C≡C-C≡CH2CH3 + NaH + NH3 
C) CH3CH2C≡CNH2 + NaH 
D) NaCH2CH2C≡CH + NH3 
E) CH3CH(Na)C≡CH + NH3 
 Ans: A 
 
Topic: Acid-Base Reactions 
 
18. Which acid-base reaction would not take place as written? 
A) CH3Li + CH3CH2OH ⎯⎯⎯⎯→ CH4 + CH3CH2OLi 
B) HC≡CH + NaOH ⎯⎯⎯⎯→ HC≡CNa + H2O 
C) HC≡CNa + H2O ⎯⎯⎯⎯→ HC≡CH + NaOH 
D) CH3OH + NaH ⎯⎯⎯⎯→ CH3ONa + H2 
E) CH3CO2H + CH3ONa ⎯⎯⎯⎯→ CH3CO2Na + CH3OH 
 Ans: E 
 
Topic: Acid-Base Reactions 
 
 19. Which acid-base reaction would not take place as written? 
A) CH3Li + CH3CH2CH2CH2NH2 ⎯⎯⎯⎯→ CH4 + CH3CH2CH2CH2NHLi 
B) CH3C≡CH + NaOCH3 ⎯⎯⎯⎯→ HC≡CNa + CH3OH 
C) HC≡CNa + H2O ⎯⎯⎯⎯→ HC≡CH + NaOH 
D) CH3OH + NaNH2 ⎯⎯⎯⎯→ CH3ONa + NH3 
E) CH3CO2H + CH3ONa ⎯⎯⎯⎯→ CH3CO2Na + CH3OH 
 Ans: B 
 
 
 
 
Chapter 3 
 
 68
Topic: Acid-Base Reactions 
 
20. Which acid-base reaction would not take place as written? 
A) CH3Li + CH3CH2OH ⎯⎯⎯⎯→ CH4 + CH3CH2OLi 
B) H2C=CH2 + NaOH ⎯⎯⎯⎯→ H2C=CHNa + H2O 
C) CH3C≡CNa + H2O ⎯⎯⎯⎯→ CH3C≡CH + NaOH 
D) (CH3)2CHOH + NaH ⎯⎯⎯⎯→ (CH3)2CHONa + H2 
E) CH3CO2H + CH3ONa ⎯⎯⎯⎯→ CH3CO2Na + CH3OH 
 Ans: B 
 
Topic: Acid-Base Reactions 
 
21. The amide ion, NH2−, is a base which can be used only in which of the solvents shown 
below: 
 A) CH3OH 
B) CH3CH2OH 
C) H2O 
D) D2O 
E) Liquid NH3 
 Ans: E 
 
Topic: Acid-Base Reactions 
 
22. Acetic acid dissociates most completely in: 
 A) CCl4 
B) Cl2C=CCl2 
C) H2O 
D) (CH3CH2)2O 
E) the gas phase. 
 Ans: C 
 
Topic: Acid-base definitions, Acid-Base Reactions 
 
23. Which pair of species are both bases in the following reaction? 
HCN and H2O ⇄ H3O+ and CN− 
 
A) H2O and CN− 
B) H3O+ and H2O 
C) HCN and H3O+ 
 D) HCN and CN− 
 E) H3O+ and CN− 
 Ans: A 
 
 
 
 
Chapter 3 
 
 69
Topic: Acid-Base Reactions 
 
24. What compounds are produced when sodium nitrate is added to a mixture of water and 
ethanol? 
A) HNO3 + NaOH 
B) HNO3 + CH3CH2ONa 
C) NaOH + CH3CH2ONa 
D) CH3CH2OCH2CH3 + NaOH 
E) No reaction occurs. 
 Ans: E 
 
Topic: Acid-Base Reactions 
 
25. Which reaction of these potential acids and bases does not occur to any appreciable 
degree due to an unfavorable equilibrium? 
A) NaOH (aq) + CH3CH2CH2CO2H 
B) CH3CH2ONa in ethanol + ethene 
C) CH3Li in hexane + ethyne 
 D) NaNH2 in liq. NH3 + ethanol 
 E) NaC2H3O2 (aq) + HI 
 Ans: B 
 
Topic: Acid-Base Reactions 
 
26. Which reaction of these potential acids and bases does not occur to any appreciable 
degree due to an unfavorable equilibrium? 
A) NaNH2 + CH3CH2CH2CH2CH2CH3 
B) CH3CH2CO2Na + HI 
C) CH3Li in hexane + ethyne 
D) NaH + methanol 
E) Two of the above will not occur 
Ans: A 
 
Topic: Acid-Base Reactions 
 
27. Which reaction of these potential acids and bases does not occur to any appreciable 
degree due to an unfavorable equilibrium? 
A) NaNH2 + CH3CH2CH2CH2CH2OH 
B) CH3CH2CO2H + NaCl 
C) NaHCO3 + CH3CH2CO2H 
D) NaH + CH3CH2CH2CH2CH2NH2 
E) all of the above will occur due to a favorable equilibrium 
 Ans: E 
 
 
 
Chapter 3 
 
 70
Topic: Acid-Base Reactions 
 
28. Which combination of reagents is the least effective in generating sodium ethoxide, 
CH3CH2ONa? 
A) CH3CH2OH + NaH 
B) CH3CH2OH + NaNH2 
C) CH3CH2OH + NaOH 
D) CH3CH2OH + CH3Li 
E) CH3CH2OH + HC≡CNa 
 Ans: C 
 
Topic: Acid-Base Reactions 
29. Which combination of reagents is effective in generating sodium ethoxide, 
CH3CH2ONa? 
 A) CH3CH2OH+ KH 
 B) CH3CH2OH + NaNH2 
 C) CH3CH2OH + Na 
 D) Two of the above 
 E) All of the above 
 Ans: E 
 
Topic: Acid-Base Reactions 
 
30. Which combination of reagents is effective in generating sodium propynide, 
CH3C≡CNa? 
 A) CH3C≡CH + KH 
 B) CH3C≡CH + (CH3)2CHONa 
 C) CH3C≡CH + C2H5Li 
 D) Two of the above 
 E) All of the above 
 Ans: B 
 
Topic: Acid-Base Reactions, base strength 
 
31. In the reaction, Na+NH2− + CH3OH ⎯⎯⎯⎯→ CH3O−Na+ + NH3, the stronger 
base is: 
A) NaNH2 
B) CH3OH 
C) CH3ONa 
 D) NH3 
 E) This is not an acid-base reaction. 
 Ans: A 
 
 
 
 
Chapter 3 
 
 71
Topic: Acid-Base Reactions, isotope labeling 
 
32. Which sequence is the best one to use to prepare CH3C≡CD? 
A) CH3C CH
NaH D2O
 
 
B) CH3C CH
NaOH D2O 
 
C) 
CH3C CH
CH3ONa D2O
D) CH3C CH
DOH
 
E) None of these will be successful. 
 Ans: A 
 
Topic: Acid-Base Reactions 
 
33. Adding sodium hydride, NaH, to water produces: 
A) H2 and NaOH(aq) 
B) H-(aq) + Na+(aq) 
C) H3O+(aq) + Na+(aq) 
 D) H3O−(aq) + Na+(aq) 
 E) Na2O + H2 
 Ans: A 
 
Topic: Acid-Base Reactions 
 
34. Adding methyllithium , CH3Li, to ethanol produces: 
A) CH3CH2Li + CH3OH 
B) CH3CH2OLi + CH4 
C) CH3CH2OCH3 + LiH 
D) All of the above 
E) No reaction takes place 
 Ans: A 
 
Topic: Acid-Base Reactions, isotope labeling 
 
35. Which reaction will yield CH3CH2-D? 
A) CH3CH3 + D2O 
B) CH3CH2Li + D2O 
C) CH3CH2OLi + D2O 
 D) CH3CH2OH + D2O 
 E) More than one of these 
 Ans: B 
 
 
 
Chapter 3 
 
 72
Topic: Acid-Base Reactions, isotope labeling 
 
36. A product of the reaction, CH3CH2Li + D2O ⎯⎯⎯⎯→ is 
A) CH3CH2OD 
B) CH3CH2CH2CH3 
C) CH2=CH2 
 D) CH3CH2D 
 E) CH3CH2OCH2CH3 
 Ans: D 
 
Topic: Relative acid strength 
 
37. The compounds ethane, ethene, and ethyne exhibit this order of increasing acidity: 
A) Ethyne < ethene < ethane 
B) Ethene < ethyne < ethane 
C) Ethane < ethyne < ethene 
 D) Ethane < ethene < ethyne 
 E) Ethene < ethane < ethyne 
 Ans: D 
 
Topic: Relative acid/base strength 
 
38. Which is an incorrect statement? 
A) RSH compounds are stronger acids than ROH compounds. 
B) PH3 is a weaker base than NH3. 
C) NH2− is a stronger base than OH−. 
D) OH− is a stronger base than OR−. 
E) H− is a stronger base than OR−. 
 Ans: D 
 
Topic: Relative acid/base strength 
 
39. The correct sequence of the ions shown, in order of increasing basicity, is: 
A) CH3CH2:− < CH2=CH:− < HC≡C:− 
B) CH3CH2:− < HC≡C:− < CH2=CH:− 
C) HC≡C:− < CH3CH2:− < CH2=CH:− 
 D) CH2=CH:− < HC≡C:− < CH3CH2:− 
 E) HC≡C:− < CH2=CH:− < CH3CH2:− 
 Ans: E 
 
 
 
 
 
 
 
Chapter 3 
 
 73
 
 
Topic: Solvent effects 
 
40. Which is a protic solvent? 
 A) CCl4 
B) HCCl3 
C) CH3OH 
D) CH3(CH2)4CH3 
E) CH3CH2OCH2CH3 
Ans: C 
 
Topic: Solvent effects 
 
41. Which might be used as protic solvent? 
A) 
O
O
 
B) 
H2N 
C) 
N
O
 
D) 
O 
E) O
 
 Ans: B 
 
Topic: Solvent effects 
 
42. Which of the following classes of substances cannot be used as protic solvents? 
A) esters 
B) aldehydes 
C) ketones 
D) carboxylic acids 
E) two of the above 
 Ans: D 
 
 
 
 
 
 
 
Chapter 3 
 
 74
Topic: Acid constants 
 
43. If a 0.01 M solution of a weak acid has a pH of 4.0, the pKa of the acid is: 
 A) 10.0 
B) 8.0 
C) 6.0 
D) 4.0 
E) 2.0 
 Ans: C 
 
 
Topic: General 
 
44. Which one of the following is a true statement? 
A) The stronger the acid, the larger is its pKa. 
B) The conjugate base of a strong acid is a strong base. 
C) Acid-base reactions always favor the formation of the stronger acid and the stronger 
base. 
D) Strong acids can have negative pKa values. 
E) Hydrogen need not be present in the molecular formula of a Bronsted-Lowry acid. 
 Ans: D 
 
Topic: Relative acid/base strengths 
 
45. The basic species are arranged in decreasing order of basicity in the sequence: 
A) F− > OCH3− > NH2− > CH3CH2− 
B) OCH3− > CH3CH2− > NH2− > F− 
C) CH3CH2− > NH2− > OCH3− > F− 
 D) NH2− > CH3CH2− > F− > OCH3− 
 E) NH2− > OCH3− > CH3CH2− > F− 
 Ans: C 
 
Topic: pKa calculations 
 
46. A particular acid has Ka = 2.0 x 10-5 (in aqueous solution). The evaluation of which of 
these expressions gives the value for pKa? 
A) 10-14/2.0 x 10-5 
B) 10-14(2.0 x 10-5) 
C) 5 – log 2.0 
D) -5 + log 2.0 
E) 2.0 x 10-5/10-14 
Ans: C 
 
 
 
 
Chapter 3 
 
 75
Topic: Solvent effects 
 
47. As a consequence of the "leveling effect," the strongest acid which can exist in 
appreciable concentration in aqueous solution is: 
 A) H3O+ 
B) H2SO4 
C) HClO4 
D) HCl 
E) HNO3 
 Ans: A 
 
Topic: Relative acid/base strengths 
 
48. Based on the position of the central atom in the periodic chart, we predict that the 
strongest acid of the following is: 
 A) H2O 
B) H2S 
C) H2Se 
D) H2Te 
 Ans: D 
 
Topic: Acid dissociation, thermodynamic calculations 
 
49. An acid, HA, has the following thermodynamic values for its dissociation in water at 
27º C: ΔH = -8.0 kJ mol-1; ΔS = -70 kJ K-1mol-1. The ΔG for the process is: 
A) +29 kJ mol-1 
B) +13 kJ mol-1 
C) -6.1 kJ mol-1 
 D) -13 kJ mol-1 
 E) -29 kJ mol-1 
 Ans: B 
 
Topic: Relative acid/base strengths, solvent effects 
 
50. Which of these bases is the strongest one which can be used (and retains its basic 
character) in aqueous solution? 
 A) OCH3− 
B) F− 
C) OH− 
D) C2H3O2− 
E) HSO4− 
 Ans: C 
 
 
 
 
Chapter 3 
 
 76
Topic: Acidity constant- thermodynamic principles 
 
51. The acidity constant, Ka, differs from the equilibrium constant, Keq, for the dissociation 
of the same acid in water at the same temperature and concentration in what way? 
A) Ka can be determined experimentally with less accuracy than Keq. 
B) The two terms are identical numerically. 
C) Ka is used for strong acids only; Keq for weak acids. 
D) Ka is the reciprocal of Keq. 
E) Keq = Ka/[H2O]. 
 Ans: E 
 
Topic: Acids/bases-general principles 
 
52. Which of the following is an untrue statement? 
A) The % dissociation of a weak acid increases with increasing dilution of the acid 
solution. 
B) The stronger an acid, the weaker its conjugate base. 
C) The larger the value of Ka for an acid, the smaller the value of its pKa. 
D) Comparison of the acidity of strong acids in solution requires the use of a solvent 
less basic than water. 
E) The stronger the acid, the more positive the value of ΔGº for the dissociation. 
 Ans: E 
 
Topic: Acid-base reactions 
53. When proton transfer reactions reach equilibrium, there have been formed: 
A) the weaker acid and the weaker base. 
B) the weaker acid and the stronger base. 
C) the stronger acid and the weaker base. 
D) the stronger acid and the stronger base. 
E) All proton transfers go to completion; they are not equilibrium processes. 
 Ans: A 
 
Topic: Relative acid-base strengths 
 
54. For the simple hydrides, MHn, pKa values decrease in the order: 
A) CH4 > NH3 > H2O > H2S > HBr 
B) HBr > H2S > H2O > NH3 > CH4 
C) HBr > H2O > NH3 > H2S > CH4 
 D) NH3 > H2S > CH4 > H2O > HBr 
 E) H2S > H2O > HBr > NH3 > CH4 
 Ans: A 
 
 
 
 
 
Chapter 3 
 
 77Topic: Relative acid-base strengths, solvent effects 
 
55. The compound aniline, C6H5NH2, has weakly basic properties in aqueous solution. In 
this other solvent, aniline would behave as a strong base. 
A) CH3OH 
B) CH3CH2OH 
C) CF3CO2H 
 D) Liquid NH3 
 E) CH3(CH2)4CH3 
 Ans: C 
 
Topic: Relative acid-base strengths 
 
56. Which of the following organic compounds is the strongest acid? 
A) C6H12 pKa = 52 
B) CH3CH3 pKa = 50 
C) CH3CH2OH pKa = 18 
 D) CH3CO2H pKa = 5 
 E) CF3CO2H pKa = 0 
 Ans: E 
 
Topic: Relative acid-base strengths 
 
57. Which is the strongest acid? 
 A) CH3CH2OH 
B) CH3CO2H 
C) HC≡CH 
D) CH2=CH2 
E) CH3CH3 
 Ans: B 
 
Topic: Relative acid-base strengths 
 
58. Which is the strongest acid? 
A) CH2ClCH2CH2CH2CH2CO2H 
B) CH3CHBrCH2CH2CH2CO2H 
C) CH3CH2CH2CBr2CH2CO2H 
D) CH3CH2CH2CHFCH2CO2H 
E) CH3CH2CH2CF2CH2CO2H 
 Ans: E 
 
 
 
 
 
Chapter 3 
 
 78
Topic: Relative acid-base strengths 
 
59. Which is the strongest acid? 
A) CH3CH2CH2CH2CHFCO2H 
B) CH3CHBrCH2CH2CH2CO2H 
C) CH3CH2CH2CHClCH2CO2H 
D) CH3CH2CH2CHFCH2CO2H 
E) CH3CH2CH2CHICH2CO2H 
 Ans: A 
 
Topic: Relative acid-base strengths 
 
60. Which is the weakest acid? 
A) CH3CH2CH2CH2CHFCO2H 
B) CH3CHCH2CH2CH2CH2OH 
C) CH3CH2CH2CH2CH2SO3H 
D) CH3CH2CH2CH2CH=CH2 
E) CH3CH2CH2CH2NH2 
 Ans: A 
 
Topic: Relative acid-base strengths 
 
61. Which of the following substances has a hydrogen atom with pKa ≈25? 
A) CH3CH2CH2CH2CO2H 
B) CH3CHCH2C≡CCH3 
C) CH3CH2CH2C≡CH 
D) CH3CH2CH2CH2CH=CH2 
E) CH3CH2CH2CH2NH2 
 Ans: C 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 3 
 
 79
Topic: Relative acid-base strengths 
 
62. Hydrogen atom(s) from which position(s) is (are) most likely to be abstracted when the 
following substance is treated with NaH? 
 
1
2
3
4
8
5
6
7
910
 
 
A) 1 
B) 1, 5, 6 
C) 1, 2 
D) 3, 4, 7, 8, 9, 10 
E) Hydrogens from all of the positions are equally likely to be abstracted by NaH. 
 Ans: A 
 
Topic: Relative acid-base strengths 
 
63. Which of the following correctly lists the compounds in order of decreasing acidity? 
A) H2O > HC≡CH > NH3 > CH3CH3 
B) HC≡CH > H2O > NH3 > CH3CH3 
C) CH3CH3 > HC≡CH > NH3 > H2O 
 D) CH3CH3 > HC≡CH > H2O > NH3 
 E) H2O > NH3 > HC≡CH > CH3CH3 
 Ans: A 
 
Topic: Relative acid-base strengths 
 
64. Select the strongest base. 
 A) OH− 
B) RC≡C− 
C) NH2− 
D) CH2=CH− 
E) CH3CH2− Ans: E 
 
 
 
 
 
 
 
 
 
 
Chapter 3 
 
 80
Topic: Relative acid-base strengths 
 
65. A group of acids arranged in order of decreasing acidity is: 
 HNO3 > CH3COOH > C6H5OH > H2O > HC≡CH 
What is the arrangement of the conjugate bases of these compounds in decreasing order 
of basicity? 
A) NO3− > CH3COO− > C6H5O− > OH− > HC≡C− 
B) CH3COO− > C6H5O− > NO3− > OH− > HC≡C− 
C) C6H5O− > NO3− > HC≡C− > OH− > CH3COO− 
D) HC≡C− > OH− > C6H5O− > CH3COO− > NO3− 
E) No prediction of relative base strength is possible. 
 Ans: D 
 
Topic: Relative acid-base strengths 
 
66. What prediction can be made of the relative strengths of the conjugate bases of: H2S, 
HCl, SiH4, PH3? 
A) PH2− > SiH3− > HS− > Cl− 
B) SiH3− > PH2− > HS− > Cl− 
C) Cl− > HS− > PH2− > SiH3− 
 D) HS− > Cl− > SiH3− > PH2− 
 E) Cl− > PH2− > SiH3− > HS− 
 Ans: B 
 
Topic: Acids/bases- general 
 
67. Which of these species is not amphoteric? 
 A) HC≡C− 
B) HS− 
C) NH3 
D) CH3− 
E) HPO4− 
 Αns: D 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 3 
 
 81
Topic: Acids/bases- general 
 
68. Which of these phosphorus-based acids is dibasic? 
A) 
P
O
OH
OHHO
 
B) 
P
O
H
OHHO
 
C) 
P
O
OH
HH
 
D) 
P
O
OH
OHO P
O
OH
OH 
E) 
P
O
OH
PHO
O
OH
OH
 
 Ans: B 
 
Topic: Acids/bases- general 
 
69. Why cannot one determine the relative acid strengths of HClO4 and HNO3 using 
aqueous solutions of these acids? 
A) The acids are insufficiently soluble for the measurements. 
B) A more basic solvent than H2O must be used. 
C) H2O is too basic a solvent for the distinction to be made. 
D) These oxidizing acids cause redox reactions to occur. 
E) Actually, the acid strengths can be determined using aqueous solutions. 
 Ans: C 
 
Topic: Acids/bases- general 
 
70. Which of these is not a diprotic acid? 
 A) H2S 
B) H2SO4 
C) H2O 
D) (COOH)2 
E) H2PO4- 
 Ans: C 
 
 
Chapter 3 
 
 82
Topic: Acids/bases- thermodynamic principles 
 
71. Which set contains non-equivalent members? 
A) Enthalpy and heat content 
B) Endothermic reaction and +ΔH 
C) Exothermic reaction and -ΔH 
 D) Kinetic energy and energy of motion 
 E) High energy and high stability 
 Ans: E 
 
 
SHORT-ANSWER QUESTIONS: 
 
Topic: General Reactivity 
 
72. Addition reactions are characteristic of compounds with ______________. 
 Ans: multiple bonds 
 
Topic: Reaction Types 
 
73. The four basic types of reactions are: ________________. 
 Ans: substitution, addition, elimination, rearrangement 
 
Topic: Reaction Mechanisms 
 
74. The process of bond-breaking where each fragment takes away one of the electrons 
from the bond is called ____________. 
 Ans: homolysis 
 
Topic: Reaction Mechanisms 
 
75. Heterolytic bond-breaking produces __________. 
 Ans: charged fragments/ions 
 
Topic: Acids and Bases 
 
76. According to Bronsted-Lowry theory, an acid is a substance that can ____________. 
 Ans: donate a proton 
 
Topic: Acids and Bases 
 
77. According to Lewis theory, a base is a substance that can _________. 
 Ans: donate a lone pair of electrons 
 
 
 
Chapter 3 
 
 83
 
Topic: Acids and Bases 
 
78. The molecule or ion that is formed when an acid loses its proton is called the 
______________. 
 Ans: conjugate base 
 
Topic: Nucleophiles and Electrophiles 
 
79. Reagents that seek to react with a proton or some other electron-deficient center are 
called ____________. 
 Ans: nucleophiles 
 
Topic: Acids and Bases 
 
80. A substance that can donate a lone pair of electrons is a ____________ according to 
____________ theory. 
 Ans: base; Lewis 
 
Topic: Curved Arrow Notation 
 
81. When drawing mechanisms, chemists generally use curved arrows. The curved arrow 
begins with ______________ and points toward ______________. 
 Ans: a lone pair or covalent bond; a site of electron deficiency 
 
Topic: Acids and Bases 
 
82. Why do water-insoluble carboxylic acids dissolve in aqueous sodium hydroxide? 
 Ans: Because they are converted to water-soluble salts. 
 
Topic: Relative Acidity 
 
83. Bond polarization that takes place through space and through the bonds of the molecule 
is called the _____________. 
 Ans: inductive effect 
 
Topic: Energy 
 
84. What are the two fundamental types of energy? 
 Ans: potential energy and kinetic energy 
 
Topic: Types of Solvents 
 
85. Define a protic solvent. 
Ans: one that has a hydrogen atom attached to a strongly electronegative element such as 
oxygen 
Chapter 3 
 
 84
 
Topic: Relative acid strength 
 
86. Briefly, but clearly, explain why the –OH hydrogen in acetic acid (CH3CO2H) is more 
acidic than in ethanol (C2H5OH). 
 
 Ans: The greater acidity of the –OH hydrogen in acetic acid is due primarily to twofactors: resonance and inductive effects. In acetic acid, the presence of the neighboring 
carbonyl group has an electron-withdrawing inductive effect on the –OH hydrogen, 
increasing its acidity relative to ethanol, in which there is no carbonyl group. Also, 
comparison of the respective conjugate bases shows that, unlike the ethoxide ion, the 
acetate ion is stabilized by resonance. This too, is reflected in the greater acid strength 
of the corresponding acid species. 
O
H
O
O
H
O
O
O
O
O(- H+)
(- H+)
Inductive effect: 
electron withdrawing resonance stabilized anion
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 3 
 
 85
 
Topic: Relative acid strength, isotope labeling 
 
87. Isotope labeling is an important tool in the study of reaction mechanisms. How will you 
selectively deuterate the specified hydrogen atom, indicated by an arrow, in the 
following compound? Use equations to clarify your answer and briefly explain your 
rationale. 
H
 
 
 Ans: The specified hydrogen is attached to an sp-hybridized carbon and is thus more 
acidic than all the other hydrogens in the molecule. By using an appropriate strong 
base, such as NaH or NaNH2, the acetylenic hydrogen is selectively removed; adding 
D2O then replaces the lost hydrogen atom with a deuterium atom. 
H
i) NaH or NaNH2
D
ii) D2O 
 
 
 
Topic: Acid-base reactions 
 
88. Write an equation to show the reaction between ethanol, C2H5OH and methyllithium, 
CH3Li. Draw all non-bonding electrons and show electron flow with curved arrows. 
 
 
Ans: 
O
H
CH3 Li
+
O Li+ CH4+
..
..
: +..
..
:
 
 
 
Topic: Acid-base reactions, solvent selection 
 
89. You are planning to carry out a reaction between propyne, CH3C≡CH and sodium 
amide, NaNH2. You also need to choose an appropriate solvent for carrying out the 
reaction. Would ethanol be suitable for this purpose? Explain your rationale clearly. 
 
 Ans: No, ethanol would be unsuitable for carrying out the reaction between propyne and 
methyllithium. The pKa of ethanol is ~16, and sodium amide is strong enough a base to 
readily abstract a proton from the solvent ( pKa of NH3 is ~38); in doing so, it becomes 
deactivated and is no longer available to react with propyne (pKa ~25). Typically, the 
selected solvent should be chemically inert toward all substances used in the reaction, so 
that it does not interfere with the desired reaction. 
 
 
 
Chapter 3 
 
 86
 
Topic: Acid-base reactions, solvent selection 
 
90. You are planning to purify an impure sample of benzoic acid, known to be contaminated 
with naphthalene. Propose a strategy for purifying this sample, making use of acid-base 
principles, using equations to further clarify your answer. 
 Ans: Benzoic acid reacts with aqueous NaOH to form a water soluble salt, while 
naphthalene, which is not soluble in water to any appreciable extent, does not react with 
NaOH. So, upon shaking the impure sample with NaOH (aq), the naphthalene remains 
as a solid, while the benzoic acid dissolves in the aqueous medium as sodium benzoate. 
After filtration, HCl is added to the filtrate to regenerate benzoic acid, which 
precipitates as almost pure crystals. Cooling maximizes the yield of the purified 
product, after which pure crystals can be obtained by filtration. 
Alternatively, before beginning the reaction with aqueous NaOH, the impure 
sample is first dissolved in diethyl ether (benzoic acid and naphthalene are both 
soluble in ether) and placed in a separatory funnel. After shaking thoroughly 
with aqueous NaOH, the aqueous layer (which now contains sodium benzoate) is 
collected. The rest of the procedure is as described earlier. 
OH
O
NaOH
OH
O
NaOH
X
ONa
O
HCl OH
O
No reaction
water soluble
water insoluble
water insoluble water insoluble
PURE
 
 
 
 
Chapter 4 
 87
MULTIPLE CHOICE QUESTIONS 
 
Topic: Nomenclature 
 
1. 
The IUPAC name for is: 
A) 6-Ethyl-3,4-dimethylheptane 
B) 2-Ethyl-4,5-dimethylheptane 
C) 3,4,6-Trimethyloctane 
D) 3,5,6-Trimethyloctane 
E) 2-(1-Methylpropyl)-4-methylhexane 
Ans: C 
 
Topic: Nomenclature 
 
2. 
An IUPAC name for is: 
A) 5-Methyl-4-(1-methylpropyl)hexane 
B) 2-Methyl-3-(1-methylpropyl)hexane 
C) 2-Methyl-3-(2-methylpropyl)hexane 
D) 3-Methyl-4-(1-methylethyl)heptane 
E) 5-Methyl-4-(1-methylethyl)heptane 
Ans: D 
 
Topic: Nomenclature 
 
3. A correct IUPAC name for the following compound is: 
 
A) 2,5-Dimethyl-3-propylheptane 
B) 3,6-Dimethyl-5-propylheptane 
C) 6-Methyl-4-(1-methylethyl)octane 
D) 2-Methyl-3-(2-methylbutyl)hexane 
E) 3-Methyl-5-(1-methylethyl)octane 
Ans: E 
 
 
Chapter 4 
 88
 
 
Topic: Nomenclature 
 
4. A correct IUPAC name for the following compound is: 
OH Cl 
A) 4-propyl-5-chloro-3-heptanol 
B) 4-propyl-3-chloro-5-heptanol 
C) 4-(1-chloropropyl)-3-heptanol 
D) 5-chloro-4-propyl-3-heptanol 
E) 3-hydroxy-4-propyl-5-chloroheptane 
Ans: D 
 
Topic: Nomenclature 
 
5. Which of the following pairs of compounds represent pairs of constitutional isomers? 
A) 2-Methylbutane and pentane 
B) 2-Chlorohexane and 3-chlorohexane 
C) sec-Butyl bromide and tert-butyl bromide 
D) Propyl chloride and isopropyl chloride 
E) All of the above 
Ans: E 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 4 
 89
Topic: Nomenclature 
 
6. Which of the following is bicyclo[3.2.2]nonane? 
 
I II III
IV V
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: C 
 
Topic: Nomenclature 
 
7. Select the systematic name for 
HCl
H Cl 
A) cis-1,3-Dichlorocyclopentane 
B) trans-1,4-Dichlorocyclopentane 
C) cis-1,2-Dichlorocyclopentane 
D) trans-1,3-Dichlorocyclopentane 
E) 1,1-Dichlorocyclopentane 
Ans: D 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Chapter 4 
 90
Topic: Nomenclature 
 
8. Which compound is a bicycloheptane? 
 
I II III
IV V
A) I 
B) II 
C) III 
D) IV 
E) V 
Ans: D 
 
Topic: Nomenclature 
 
9. Which isomer of C5H10 would you expect to have the smallest heat of combustion? 
A) Cyclopentane 
B) Methylcyclobutane 
C) 1,1-Dimethylcyclopropane 
D) cis-1,2-Dimethylcyclopropane 
E) trans-1,2-Dimethylcyclopropane 
Ans: A 
 
Topic: Nomenclature 
 
10. Which is the correct name for the compound shown below? 
 
A) Bicyclo[2.2.0]hexane 
B) Bicyclo[2.2.0]butane 
C) Bicyclo[2.2.2]hexane 
D) Bicyclo[2.2.1]hexane 
E) Disquarane 
Ans: A 
 
 
 
 
 
Chapter 4 
 91
Topic: Nomenclature 
 
11. What is the name of this compound? 
 
A) Bicyclo[2.2.2]octane 
B) Bicyclo[3.2.1]octane 
C) Bicyclo[4.1.1]octane 
D) Bicyclo[4.2.0]octane 
E) Bicyclo[3.3.0]octane 
Ans: D 
 
Topic: Nomenclature 
 
12. What is the common name for this compound? 
 
Br
 
A) Isobutyl bromide 
B) tert-Butyl bromide 
C) Butyl bromide 
D) sec-Butyl bromide 
E) Bromo-sec-butane 
Ans: A 
 
Topic: Nomenclature 
 
13. A correct IUPAC name for the following compound is: 
Br
 
A) 3,6,7-trimethyl-4-bromo-1-octene 
B) 4-bromo-3-methyl-6-isopropyl-1-heptene 
C) 4-bromo-3,6,7-trimethyl-1-octene 
D) 4-bromo-6-isopropyl-3-methyl-1-heptene 
E) 4-bromo-6-isopropyl-3,6-dimethyl-1-hexene 
Ans: C 
 
 
 
 
 
 
 
 
Chapter 4 
 92
Topic: Nomenclature 
 
14. A correct name for the following compound is: 
 
A) 2-Methylbicyclo[4.3.0]nonane 
B) 1-Methylbicyclo[4.3.1]nonane 
C) 7-Methylbicyclo[4.3.0]nonane 
D) 2-Methylbicyclo[4.3.1]nonane 
E) 1-Methylbicyclo[4.3.0]nonane 
Ans: A 
 
Topic: Nomenclature 
 
Use the following to answer questions 15-17: 
 
I II III
IV V 
 
 
15. Which of the above is bicyclo[3.3.1]nonane? 
A) I 
B) II 
C) III 
D)