Question 1

During the nitration of a benzene ring in a mixture of HNO3 and H2SO4 the following species reacts as an electrophile:

Accepted Answer

A)  H3O+ 
B)  H3SO4+ 
C)  H2NO3+ 
D)  H+ 
E)  NO2+ 
A)  H3O+ 
B)  H3SO4+ 
C)  H2NO3+ 
D)  H+ 
E)  NO2+

Question 2

Give the correct mathematical expression for the rate law for E2 reactions (S is a substrate and B is a base).

Accepted Answer

A)  rate = k[S] 
B)  rate = k[B] 
C)  rate = k[S][B] 
D)  rate = k[S]1/2 
E)  rate = k[S]2 
A)  rate = k[S] 
B)  rate = k[B] 
C)  rate = k[S][B] 
D)  rate = k[S]1/2 
E)  rate = k[S]2

Question 3

What product would you expect to obtain from a reaction between one isomer of 3-methyl-1-pentanol and HI?

Accepted Answer

A)  a substitution product with retention of configuration 
B)  only one elimination product 
C)  a substitution product with inversion of configuration 
D)  two elimination products 
E)  a racemic mixture of substitution products 
A)  a substitution product with retention of configuration 
B)  only one elimination product 
C)  a substitution product with inversion of configuration 
D)  two elimination products 
E)  a racemic mixture of substitution products

Question 4

What alkene(s) would be produced in the following reaction?

Accepted Answer

A)  3-methyl-2-pentene 
B)  2-methyl-2-butene 
C)  3-methylbutene 
D)  pentene and 1-methylpentene 
E)  2-methyl-2-butene and 3-methylbutene 
A)  3-methyl-2-pentene 
B)  2-methyl-2-butene 
C)  3-methylbutene 
D)  pentene and 1-methylpentene 
E)  2-methyl-2-butene and 3-methylbutene

Question 5

Which of the following are nucleophiles? 
I. CH3C(O)CH3 
II. CH3Br 
III. CH3CH2C≡C-

Accepted Answer

A)  I 
B)  II 
C)  III 
D)  I + II 
E)  I + III 
A)  I 
B)  II 
C)  III 
D)  I + II 
E)  I + III

Question 6

The following can be said about the reaction profile of an SN1 reaction: 
I. The rate determining step is formation of carbocation.
II. The reaction profile has one transition state.
III. The slow step is the first transition state.
IV. The second step is attack of electrophile on carbocation.
V.The reaction proceeds in a polar aprotic solvent.

Accepted Answer

A)  I, III, and IV 
B)  I, II and IV 
C)  II, III and IV 
D)  I, II and V 
E)  II, IV and V 
A)  I, III, and IV 
B)  I, II and IV 
C)  II, III and IV 
D)  I, II and V 
E)  II, IV and V

Question 7

Write down the rate law for E1 reactions (S is a substrate and B is a base).

Accepted Answer

A)  rate = k[S] 
B)  rate = k[S][B] 
C)  rate = k[B] 
D)  rate = k[S]2 
E)  rate = k[S]1/2 
A)  rate = k[S] 
B)  rate = k[S][B] 
C)  rate = k[B] 
D)  rate = k[S]2 
E)  rate = k[S]1/2

Question 8

The alkanes are known for their reactivity

Accepted Answer

A) True 
 B)False

Question 9

Which of the following alcohols can eliminate water to produce alkene? 
 I) phenol
II) HOC(CH3)3
III) HOCH(CH3)2

Accepted Answer

A)  II) and III) 
B)  I), II) and III) 
C)  III) only 
D)  I) and II) 
E)  II) only 
A)  II) and III) 
B)  I), II) and III) 
C)  III) only 
D)  I) and II) 
E)  II) only

Question 10

Which of the following statements correctly describe SN2 and SN1 reactions?
 I. SN2 reactions proceed with retention of configuration.
II. SN1  reactions prefer polar protic solvents
III. SN1  reactions produce racemic products
IV. SN2 reactions are promoted in the presence of a substrate that produces a very stable carbocation
V.SN1  reactions have a unimolecular rate-determining step.

Accepted Answer

A)  I, II and V 
B)  II, III, and IV 
C)  III, IV and V 
D)  II, III and V 
E)  I, III, and IV 
A)  I, II and V 
B)  II, III, and IV 
C)  III, IV and V 
D)  II, III and V 
E)  I, III, and IV

Question 11

Electrophilic substitution reactions are typical reactions of aromatic compounds.

Accepted Answer

A) True 
 B)False

Question 12

Finish the sentence: "Elimination reactions....

Accepted Answer

A)  ...can follow two different mechanisms." 
B)  ...do not compete with other reaction types." 
C)  ...usually give a saturated product." 
D)  ...always give only one product." 
E)  ...have only one mechanistic path." 
A)  ...can follow two different mechanisms." 
B)  ...do not compete with other reaction types." 
C)  ...usually give a saturated product." 
D)  ...always give only one product." 
E)  ...have only one mechanistic path."

Question 13

Complete the following reaction: NH3 + CH3Br →

Accepted Answer

A)  CH4 + NH2Br 
B)  CH2=NH + H2 + HBr 
C)  CH3NH2 + NH4+Br- 
D)  CH3NH3+Br- 
E)  There is no reaction. 
A)  CH4 + NH2Br 
B)  CH2=NH + H2 + HBr 
C)  CH3NH2 + NH4+Br- 
D)  CH3NH3+Br- 
E)  There is no reaction.

Question 14

Which reagents would you choose to carry out the following transformations? I)   II)   III)

Accepted Answer

A)  Reaction I use KOtBu Reaction II use MeOH
Reaction III use NaOCH(CH3)2 
B)  Reaction I use NaOMe Reaction II use MeOH
Reaction III use NaOC(CH3)3 
C)  Reaction I use NaOMe Reaction II use MeOH
Reaction III use NaOMe 
D)  Reaction I use KOtBu Reaction II use HC(=O)H
Reaction III use NaOCH(CH3)2 
E)  Reaction I use KOtBu Reaction II use Na2Cr2O7 or K2Cr2O7
Reaction III use NaOCH(CH3)2 
A)  Reaction I use KOtBu Reaction II use MeOH
Reaction III use NaOCH(CH3)2 
B)  Reaction I use NaOMe Reaction II use MeOH
Reaction III use NaOC(CH3)3 
C)  Reaction I use NaOMe Reaction II use MeOH
Reaction III use NaOMe 
D)  Reaction I use KOtBu Reaction II use HC(=O)H
Reaction III use NaOCH(CH3)2 
E)  Reaction I use KOtBu Reaction II use Na2Cr2O7 or K2Cr2O7
Reaction III use NaOCH(CH3)2

Question 15

The rate of E2 reaction between an alkyl halide RX and a base B is given by the following expression (k is a rate constant):

Accepted Answer

A)  k[RX} 
B)  k[B] 
C)  k[RX]{B] 
D)  k{RX]2 
E)  k{RX]2[B] 
A)  k[RX} 
B)  k[B] 
C)  k[RX]{B] 
D)  k{RX]2 
E)  k{RX]2[B]

Question 16

What type of polymerization reaction occurred to produce the following polymer?

Accepted Answer

A)  addition polymerization 
B)  elimination reaction 
C)  chain-reaction polymerization 
D)  condensation polymerization 
E)  propagation polymerization 
A)  addition polymerization 
B)  elimination reaction 
C)  chain-reaction polymerization 
D)  condensation polymerization 
E)  propagation polymerization

Question 17

Which of the following trends in nucleophilicity are correct? 
I. Everything else being equal, a negatively charged nucleophile will react faster than a neutral one.
II. Generally, species containing elements of high electronegativity are good nucleophiles.
III. Anionic nucleophiles are more reactive in polar and aprotic solvents than in polar and protic solvents
IV. Generally, nucleophilicity is increasing with the increase in size of an atom.
V. Bulky groups adjacent to the nucleophilic atom enhance the nucleophilicity and reactivity of the species.

Accepted Answer

A)  I, III, and V 
B)  II, III and V 
C)  I, II and IV 
D)  II, III and V. 
E)  III, IV and V 
A)  I, III, and V 
B)  II, III and V 
C)  I, II and IV 
D)  II, III and V. 
E)  III, IV and V

Question 18

Classify the following polymers as atactic, isotactic or syndiotactic:

Accepted Answer

A)  Polymer A is isotactic, polymer B is atactic and polymer C is syndiotactic 
B)  Polymer A is atactic, polymer B is isotactic and polymer C is syndiotactic 
C)  Polymers A and B are isotactic and polymer C is syndiotactic 
D)  Polymer A is isotactic and polymers B and C is syndiotactic 
E)  Polymer A is syndiotactic, polymer B is isotactic and polymer C is atactic 
A)  Polymer A is isotactic, polymer B is atactic and polymer C is syndiotactic 
B)  Polymer A is atactic, polymer B is isotactic and polymer C is syndiotactic 
C)  Polymers A and B are isotactic and polymer C is syndiotactic 
D)  Polymer A is isotactic and polymers B and C is syndiotactic 
E)  Polymer A is syndiotactic, polymer B is isotactic and polymer C is atactic

Question 19

Which of the four positions 1-4 marked on the structure of aromatic compound shown below would be preferentially substituted in an electrophilic aromatic substitution reaction?

Accepted Answer

A)  4 only 
B)  2 and 4 
C)  2 only 
D)  1 and 3 
E)  3 only 
A)  4 only 
B)  2 and 4 
C)  2 only 
D)  1 and 3 
E)  3 only

Question 20

Predict the product and mechanism type for the following reaction:

Accepted Answer

A) 
 
SN2 mechanism 
B) 
 
SN2 mechanism 
C) 
 
SN1 mechanism 
D) 
 
SN1 mechanism 
E) 
 
SN1 mechanism 
A) 
 
SN2 mechanism 
B) 
 
SN2 mechanism 
C) 
 
SN1 mechanism 
D) 
 
SN1 mechanism 
E) 
 
SN1 mechanism

Exam 27: Reactions of Organic Compounds

During the nitration of a benzene ring in a mixture of HNO3 and H2SO4 the following species reacts as an electrophile:

Give the correct mathematical expression for the rate law for E2 reactions (S is a substrate and B is a base).

What product would you expect to obtain from a reaction between one isomer of 3-methyl-1-pentanol and HI?

What alkene(s) would be produced in the following reaction?

Which of the following are nucleophiles? I. CH3C(O)CH3 II. CH3Br III. CH3CH2C≡C-

Write down the rate law for E1 reactions (S is a substrate and B is a base).

The alkanes are known for their reactivity

Which of the following alcohols can eliminate water to produce alkene? I) phenol II) HOC(CH3)3 III) HOCH(CH3)2

Electrophilic substitution reactions are typical reactions of aromatic compounds.

Finish the sentence: "Elimination reactions....

Complete the following reaction: NH3 + CH3Br →

Which reagents would you choose to carry out the following transformations? I) II) III)

The rate of E2 reaction between an alkyl halide RX and a base B is given by the following expression (k is a rate constant):

What type of polymerization reaction occurred to produce the following polymer?

Classify the following polymers as atactic, isotactic or syndiotactic:

Which of the four positions 1-4 marked on the structure of aromatic compound shown below would be preferentially substituted in an electrophilic aromatic substitution reaction?

Predict the product and mechanism type for the following reaction:

Matter - Its Properties and Measurement

Atoms and the Atomic Theory

Chemical Compounds

Chemical Reactions

Introduction to Reactions in Aqueous Solutions

Gases

Thermochemistry

Electrons in Atoms

The Periodic Table and Some Atomic Properties

Chemical Bonding I: Basic Concepts

Chemical Bonding II: Additional Aspects

Intermolecular Forces: Liquids and Solids

Solutions and Their Physical Properties

Chemical Kinetics

Principles of Chemical Equilibrium

Acids and Bases

Additional Aspects of Acid-Base Equilibria

Solubility and Complex-Ion Equilibria

Spontaneous Change: Entropy and Free Energy

Electrochemistry

Main Group Elements I: Groups 1, 2, 13, and 14

Main Group Elements II: Groups 18, 17, 16, 15, and Hydrogen

The Transition Elements

Complex Ions and Coordination Compounds

Nuclear Chemistry 1-41

Structures of Organic Compounds

Chemistry of the Living State

Filters

During the nitration of a benzene ring in a mixture of HNO₃ and H₂SO₄ the following species reacts as an electrophile:

Which of the following are nucleophiles? I. CH₃C(O)CH₃ II. CH₃Br III. CH₃CH₂C≡C^-

Which of the following alcohols can eliminate water to produce alkene? I) phenol II) HOC(CH₃)₃ III) HOCH(CH₃)₂

Complete the following reaction: NH₃ + CH₃Br →