Question 1

What is the starting material in the reaction shown below?

Accepted Answer

A) I 
B) II 
C) III 
D) IV 
A) I 
B) II 
C) III 
D) IV

Question 2

What is the product of the nucleophilic substitution reaction shown below?

Accepted Answer

A) Only I 
B) Only II 
C) I and II 
D) None 
A) Only I 
B) Only II 
C) I and II 
D) None

Question 3

Which of the following statements is not true?

Accepted Answer

A) Sodium ethoxide is a better nucleophile than sodium tert-butoxide. 
B) Sodium tert-butoxide and sodium ethoxide have similar strengths as bases. 
C) Sterically hindered bases are also called nonnucleophilic bases. 
D) Steric hindrance decreases basicity but not nucleophilicity. 
A) Sodium ethoxide is a better nucleophile than sodium tert-butoxide. 
B) Sodium tert-butoxide and sodium ethoxide have similar strengths as bases. 
C) Sterically hindered bases are also called nonnucleophilic bases. 
D) Steric hindrance decreases basicity but not nucleophilicity.

Question 4

What is the rate-determining step of an SN1 reaction mechanism?

Accepted Answer

A) Reaction of the nucleophile with the carbocation to form the product. 
B) Breaking the bond between the carbon and the leaving group to generate a carbocation. 
C) Attack of the nucleophile on the substrate to generate a pentavalent carbon. 
D) None of these. 
A) Reaction of the nucleophile with the carbocation to form the product. 
B) Breaking the bond between the carbon and the leaving group to generate a carbocation. 
C) Attack of the nucleophile on the substrate to generate a pentavalent carbon. 
D) None of these.

Question 5

Which of the following is not a characteristic of an SN1 reaction?

Accepted Answer

A) The rate is proportional to the concentration of substrate. 
B) The reaction is favored in polar protic solvents. 
C) The rate is independent of the concentration of the nucleophile. 
D) The electrophilic carbon undergoes inversion of stereochemistry. 
A) The rate is proportional to the concentration of substrate. 
B) The reaction is favored in polar protic solvents. 
C) The rate is independent of the concentration of the nucleophile. 
D) The electrophilic carbon undergoes inversion of stereochemistry.

Question 6

Rank the alkyl halides in order of decreasing SN2 reactivity, putting the most reactive first.

Accepted Answer

A) I > II > III 
B) II > I > III 
C) III > I > II 
D) I > III > II 
A) I > II > III 
B) II > I > III 
C) III > I > II 
D) I > III > II

Question 7

For the following reaction, use the identity of the alkyl halide and nucleophile to determine which substitution mechanism occurs.Then determine which solvent affords the faster reaction.

Accepted Answer

A) SN1, CH3OH 
B) SN1, HMPA 
C) SN2, CH3OH 
D) SN2, HMPA 
A) SN1, CH3OH 
B) SN1, HMPA 
C) SN2, CH3OH 
D) SN2, HMPA

Question 8

Which of the following carbocations is the most stable?

Accepted Answer

A) I 
B) II 
C) III 
D) IV 
A) I 
B) II 
C) III 
D) IV

Question 9

Which of the following alkyl halides is a tertiary alkyl halide?

Accepted Answer

A) I 
B) II 
C) III 
D) IV 
A) I 
B) II 
C) III 
D) IV

Question 10

What is the product of the nucleophilic substitution reaction shown below?

Accepted Answer

A) Only I 
B) Only II 
C) I and II 
D) None 
A) Only I 
B) Only II 
C) I and II 
D) None

Question 11

Rank the following in order of increasing leaving group ability, putting the worst leaving group first.

Accepted Answer

A) IV < II < III < I 
B) III < IV < I < II 
C) II < IV < I < III 
D) I < III < II < IV 
A) IV < II < III < I 
B) III < IV < I < II 
C) II < IV < I < III 
D) I < III < II < IV

Question 12

Which of the following statements is not true?

Accepted Answer

A) All good leaving groups are weak bases with strong conjugate acids. 
B) Left-to-right across a row of the periodic table, leaving group ability increases. 
C) Down a column of the periodic table, leaving group ability increases. 
D) Equilibrium favors the products of the nucleophilic substitution when the leaving group is a stronger base than the nucleophile. 
A) All good leaving groups are weak bases with strong conjugate acids. 
B) Left-to-right across a row of the periodic table, leaving group ability increases. 
C) Down a column of the periodic table, leaving group ability increases. 
D) Equilibrium favors the products of the nucleophilic substitution when the leaving group is a stronger base than the nucleophile.

Question 13

Which of the following statements explain why aryl halides and vinyl halides do not undergo nucleophilic substitution by either the SN1 or SN2 mechanism?

Accepted Answer

A) They don't undergo SN1 reactions because a higher percent s-character makes the bond longer and stronger. 
B) They don't undergo SN2 reactions because a higher percent s-character makes the bond shorter and stronger. 
C) They don't undergo SN2 reactions because heterolysis of the C-X bond forms a highly unstable carbocation. 
D) They don't undergo SN1 reactions because the carbocation is highly electronegative. 
A) They don't undergo SN1 reactions because a higher percent s-character makes the bond longer and stronger. 
B) They don't undergo SN2 reactions because a higher percent s-character makes the bond shorter and stronger. 
C) They don't undergo SN2 reactions because heterolysis of the C-X bond forms a highly unstable carbocation. 
D) They don't undergo SN1 reactions because the carbocation is highly electronegative.

Question 14

Rank the following compounds in order of increasing SN2 reactivity?

Accepted Answer

A) I > II > III > IV 
B) IV > I > II > III 
C) IV > III > II > I 
D) III > II > I > IV 
A) I > II > III > IV 
B) IV > I > II > III 
C) IV > III > II > I 
D) III > II > I > IV

Question 15

Which of the following statements about carbocation stability is true?

Accepted Answer

A) Carbocations are stabilized by electron-withdrawing inductive effects only. 
B) Carbocations are stabilized by electron-withdrawing inductive effects and hyperconjugation. 
C) Carbocations are stabilized by electron-donating inductive effects only. 
D) Carbocations are stabilized by electro-donating inductive effects and hyperconjugation. 
A) Carbocations are stabilized by electron-withdrawing inductive effects only. 
B) Carbocations are stabilized by electron-withdrawing inductive effects and hyperconjugation. 
C) Carbocations are stabilized by electron-donating inductive effects only. 
D) Carbocations are stabilized by electro-donating inductive effects and hyperconjugation.

Question 16

What is the IUPAC name of the following compound?

Accepted Answer

A) 2-Bromo-5,5-dimethylheptane 
B) 3,3-Dimethyl-6-bromoheptane 
C) 6-Bromo-3,3-dimethylheptane 
D) 2-Bromo-5,5-dimethyloctane 
A) 2-Bromo-5,5-dimethylheptane 
B) 3,3-Dimethyl-6-bromoheptane 
C) 6-Bromo-3,3-dimethylheptane 
D) 2-Bromo-5,5-dimethyloctane

Question 17

Which of the following anions is the most nucleophilic in polar aprotic solvents?

Accepted Answer

A) F- 
B) Cl- 
C) Br- 
D) I- 
A) F- 
B) Cl- 
C) Br- 
D) I-

Question 18

Rank the following molecules in order of increasing polarity, putting the least polar first.

Accepted Answer

A) IV < III < II < I 
B) I < IV < III < II 
C) I < II < III < IV 
D) II < I < III < IV 
A) IV < III < II < I 
B) I < IV < III < II 
C) I < II < III < IV 
D) II < I < III < IV

Question 19

For the following reaction, use the identity of the alkyl halide and nucleophile to determine which substitution mechanism occurs.Then determine which solvent affords the faster reaction.

Accepted Answer

A) SN1, CH3OH 
B) SN1, DMSO 
C) SN2, CH3OH 
D) SN2, DMSO 
A) SN1, CH3OH 
B) SN1, DMSO 
C) SN2, CH3OH 
D) SN2, DMSO

Question 20

What is the IUPAC name of the following compound?

Accepted Answer

A) (R)-3-Bromo-1-methylcyclohexene 
B) (S)-3-Bromo-1-methylcyclohexene 
C) (S)-1-Bromo-3-methyl-2-cyclohexene 
D) (R)-1-Bromo-3-methyl-2-cyclohexene 
A) (R)-3-Bromo-1-methylcyclohexene 
B) (S)-3-Bromo-1-methylcyclohexene 
C) (S)-1-Bromo-3-methyl-2-cyclohexene 
D) (R)-1-Bromo-3-methyl-2-cyclohexene

Exam 7: Alkyl Halides and Nucleophilic Substitution

What is the starting material in the reaction shown below?

What is the product of the nucleophilic substitution reaction shown below?

Which of the following statements is not true?

What is the rate-determining step of an SN1 reaction mechanism?

Which of the following is not a characteristic of an SN1 reaction?

Rank the alkyl halides in order of decreasing SN2 reactivity, putting the most reactive first.

For the following reaction, use the identity of the alkyl halide and nucleophile to determine which substitution mechanism occurs.Then determine which solvent affords the faster reaction.

Which of the following carbocations is the most stable?

Which of the following alkyl halides is a tertiary alkyl halide?

What is the product of the nucleophilic substitution reaction shown below?

Rank the following in order of increasing leaving group ability, putting the worst leaving group first.

Which of the following statements is not true?

Which of the following statements explain why aryl halides and vinyl halides do not undergo nucleophilic substitution by either the SN1 or SN2 mechanism?

Rank the following compounds in order of increasing SN2 reactivity?

Which of the following statements about carbocation stability is true?

What is the IUPAC name of the following compound?

Which of the following anions is the most nucleophilic in polar aprotic solvents?

Rank the following molecules in order of increasing polarity, putting the least polar first.

For the following reaction, use the identity of the alkyl halide and nucleophile to determine which substitution mechanism occurs.Then determine which solvent affords the faster reaction.

What is the IUPAC name of the following compound?

Structure and Bonding

Acids and Bases

Introduction to Organic Molecules and Functional Groups

Alkanes

Stereochemistry

Understanding Organic Reactions

Alkyl Halides and Elimination Reactions

Alcohols, Ethers, and Related Compounds

Alkenes

Alkynes

Oxidation and Reduction

Mass Spectrometry and Infrared Spectroscopy

Nuclear Magnetic Resonance Spectroscopy

Radical Reactions

Conjugation, Resonance, and Dienes

Benzene and Aromatic Compounds

Reactions of Aromatic Compounds

Carboxylic Acids and the Acidity of the O-H Bond

Introduction to Carbonyl Chemistry;

Aldehydes and Ketones Nucleophilic Addition

Carboxylic Acids and Derivatives

Substitution Reactions of Carbonyl Compounds at the Alpha-Carbon

Carbonyl Condensation Reactions

Amines

Carbon-Carbon Bond Forming Reactions in Organic Synthesis

Pericyclic Reactions

Carbohydrates

Amino Acids and Proteins

Synthetic Polymers

Lipids

Filters

What is the rate-determining step of an S_N1 reaction mechanism?

Which of the following is not a characteristic of an S_N1 reaction?

Rank the alkyl halides in order of decreasing S_N2 reactivity, putting the most reactive first.

Which of the following statements explain why aryl halides and vinyl halides do not undergo nucleophilic substitution by either the S_N1 or S_N2 mechanism?

Rank the following compounds in order of increasing S_N2 reactivity?