Exam Prep Ch.6 Chemical Reactivity And Mechanisms - Organic Chemistry 4e | Test Bank by Klein by David R. Klein. DOCX document preview.

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Exam Prep Ch.6 Chemical Reactivity And Mechanisms

Organic Chemistry, 4e (Klein)

Chapter 6 Chemical Reactivity and Mechanisms

1) Estimate the enthalpy change of the following reaction under standard conditions.

In a reaction, propyl iodide that has a SMILES string of CCCI reacts with hydrogen bromide, H B r to yield propyl bromide that has a SMILES string of CCCBr and a by-product, hydrogen iodide, H I.

A) -8 kJ/mol

B) -6 kJ/mol

C) 0 kJ/mol

D) +6 kJ/mol

E) +8 kJ/mol

Diff: 2

Learning Objective: 6.1 Define enthalpy, homolytic and heterolytic bond cleavage, discussing heat of reaction and the relation of its sign to direction of energy transfer

2) Estimate the enthalpy change of the following reaction under standard conditions.

In a reaction, butane that has a SMILES string of CCCC reacts with a molecule of iodine, I 2 to yield a product that has a SMILES string of CCC(C)I and a by-product, hydrogen iodide, H I.

A) -45 kJ/mol

B) -29 kJ/mol

C) 0 kJ/mol

D) +29 kJ/mol

E) +45 kJ/mol

Diff: 2

Learning Objective: 6.1 Define enthalpy, homolytic and heterolytic bond cleavage, discussing heat of reaction and the relation of its sign to direction of energy transfer

3) Estimate the enthalpy change of the following reaction under standard conditions.

In a reaction, a compound that has a SMILES string of CCC(C)F reacts with a molecule of water, H 2 O to yield a product that has a SMILES string of CCC(C)O and a by-product, hydrogen fluoride, H F.

A) -16 kJ/mol

B) -8 kJ/mol

C) +4 kJ/mol

D) +8 kJ/mol

E) +16 kJ/mol

Diff: 2

Learning Objective: 6.1 Define enthalpy, homolytic and heterolytic bond cleavage, discussing heat of reaction and the relation of its sign to direction of energy transfer

4) Estimate the enthalpy change of the following reaction under standard conditions.

In a reaction, a compound that has a SMILES string of CC(C)Cl reacts with a molecule of hydrogen iodide, H I to yield a product that has a SMILES string of CC(C)I and a by-product, hydrogen chloride, H C l.

A) -21 kJ/mol

B) +21 kJ/mol

C) -171 kJ/mol

D) +171 kJ/mol

Diff: 1

Learning Objective: 6.1 Define enthalpy, homolytic and heterolytic bond cleavage, discussing heat of reaction and the relation of its sign to direction of energy transfer

5) Estimate the enthalpy change of the following reaction under standard conditions.

In a reaction, a compound that has a SMILES string of CCC(C)F reacts with a molecule of water, H 2 O to yield a product that has a SMILES string of CCC(C)O and a by-product, hydrogen fluoride, H F.

A) -8 kJ/mol

B) +8 kJ/mol

C) -506 kJ/mol

D) +63 kJ/mol

Diff: 2

Learning Objective: 6.1 Define enthalpy, homolytic and heterolytic bond cleavage, discussing heat of reaction and the relation of its sign to direction of energy transfer

6) Later in the course, we will compare the halogenation of differently substituted carbons, comparing reactions like the ones below. Which of the following statements is true about reactions I and II?

An illustration shows two reactions, 1 and 2 (in Roman numerals), in which two different alkane compounds react with a molecule of bromine, B r 2 to yield a product and a by-product. In reaction 1, the reactant has a SMILES string of CCC which reacts with a molecule of bromine, B r bonded to B r, to yield a product that has a SMILES string of CC(C)Br and a by-product, hydrogen bromide, H bonded to B r. In reaction 2, the reactant has a SMILES string of CC(C)C which reacts with a molecule of bromine, B r bonded to B r, to yield a product that has a SMILES string of CC(C)(C)Br and a by-product, hydrogen bromide, H bonded to B r.

A) Both reactions have a positive heat of reaction (∆Ho)

B) Neither reaction has a positive heat of reaction (∆Ho)

C) Only reaction I has a positive heat of reaction (∆Ho)

D) Only reaction II has a positive heat of reaction (∆Ho)

Diff: 2

Learning Objective: 6.1 Define enthalpy, homolytic and heterolytic bond cleavage, discussing heat of reaction and the relation of its sign to direction of energy transfer

7) Later in the course, we will compare the halogenation of differently substituted carbons, comparing reactions like the ones below. Which of the following reactions has a more exothermic heat of reaction (∆Ho)?

An illustration shows two reactions, 1 and 2 (in Roman numerals), in which two different alkane compounds react with a molecule of bromine, B r 2 to yield a product and a by-product. In reaction 1, the reactant has a SMILES string of CCC which reacts with a molecule of bromine, B r bonded to B r, to yield a product that has a SMILES string of CC(C)Br and a by-product, hydrogen bromide, H bonded to B r. In reaction 2, the reactant has a SMILES string of CC(C)C which reacts with a molecule of bromine, B r bonded to B r, to yield a product that has a SMILES string of CC(C)(C)Br and a by-product, hydrogen bromide, H bonded to B r.

A) Reaction I has a more exothermic heat of reaction (∆Ho)

B) Reaction II has a more exothermic heat of reaction (∆Ho)

C) Reaction I has a more exothermic heat of reactions ((∆Ho) at low temperatures and the opposite is true at high temperatures

D) Both reactions consistently have the same heat of reaction (∆Ho)

E) It is impossible to determine from the information given.

Diff: 2

Learning Objective: 6.1 Define enthalpy, homolytic and heterolytic bond cleavage, discussing heat of reaction and the relation of its sign to direction of energy transfer

8) You are working in a research laboratory and have developed a new reagent that cleaves C-H bonds homolytically. Unfortunately, this reagent can achieve only one of the transformations shown below. In light of the known bond dissociation energies, which transformation is most likely to be achieved?

An illustration shows two reaction, 1 and 2 (in Roman numerals), in which two different reactants react with a new reagent to yield a free radical. In reaction 1, the reactant has a SMILES string of C=CC which reacts with a "new reagent" to yield a product that has a similar structure as the reactant except C 3 has an unpaired electron. In reaction 2, the reactant has a SMILES string of c1ccccc1 which reacts with a "new reagent" to yield a product that has a similar structure as the reactant except C 1 has an unpaired electron. Another illustration shows two reaction, 3 and 4 (in Roman numerals), in which two different reactants react with a new reagent to yield a free radical. In reaction 3, the reactant has a SMILES string of C=C which reacts with a "new reagent" to yield a product that has a similar structure as the reactant except C 1 has an unpaired electron. In reaction 4, the reactant has a SMILES string of C which reacts with a "new reagent" to yield a product that has a similar structure as the reactant except the carbon atom has an unpaired electron.

A) I

B) II

C) III

D) IV

E) V

Diff: 3

Learning Objective: 6.1 Define enthalpy, homolytic and heterolytic bond cleavage, discussing heat of reaction and the relation of its sign to direction of energy transfer

9) What type of bond cleavage does the following reaction involve?

An illustration shows conversion of hydrogen peroxide, H O O H into two free radicals of hydroxide, O H, in which the oxygen atom has an unpaired electron.

A) homolytic

B) heterolytic

C) covalent

D) ionic

Diff: 1

Learning Objective: 6.1 Define enthalpy, homolytic and heterolytic bond cleavage, discussing heat of reaction and the relation of its sign to direction of energy transfer

10) What type of bond cleavage does the following reaction involve?

In a reaction, a compound that has a SMILES string of CC(C)(C)Br converts into a cation and anion. The cation has a SMILES string of CC(C)(C)Br in which C 2 has a positive charge. The anion has a bromine atom that carries a negative charge.

A) homolytic

B) heterolytic

C) covalent

D) ionic

Diff: 1

Learning Objective: 6.1 Define enthalpy, homolytic and heterolytic bond cleavage, discussing heat of reaction and the relation of its sign to direction of energy transfer

11) In a homolytic bond cleavage, ________ are formed.

A) ions

B) radicals

C) only cations

D) only anions

Diff: 1

Learning Objective: 6.1 Define enthalpy, homolytic and heterolytic bond cleavage, discussing heat of reaction and the relation of its sign to direction of energy transfer

12) In a heterolytic bond cleavage, ________ are formed.

A) ions

B) radicals

C) only cations

D) only anions

Diff: 1

Learning Objective: 6.1 Define enthalpy, homolytic and heterolytic bond cleavage, discussing heat of reaction and the relation of its sign to direction of energy transfer

13) Predict the sign of ∆S for the following reaction.

In a reaction, a compound that has a SMILES string of C#C reacts with a compound that has a SMILES string of CCN=[N+]=[N-] to yield a product that has a SMILES string of n1nn(cc1)CC.

A) positive

B) negative

C) no change

Diff: 1

Learning Objective: 6.2 Define entropy, discussing the role of entropy in spontaneous processes

14) Predict the sign of ∆S for the following reaction.

An illustration shows conversion of a compound that has a SMILES string of CC(C)(C)Br into a compound that has a SMILES string of CC(=C)C and a molecule of hydrogen bromide, H B r.

A) positive

B) negative

C) no change

Diff: 1

Learning Objective: 6.2 Define entropy, discussing the role of entropy in spontaneous processes

15) Predict the sign of ∆S for the following reaction.

An illustration shows conversion of a compound that has a SMILES string of C=CCCCO into a compound that has a SMILES string of CC1CCCO1.

A) positive

B) negative

C) no change

Diff: 1

Learning Objective: 6.2 Define entropy, discussing the role of entropy in spontaneous processes

16) Predict the sign of ∆S for the following reaction.

An illustration shows conversion of a compound that has a SMILES string of CC1CCCO1 into a compound that has a SMILES string of C=CCCCO.

A) positive

B) negative

C) no change

Diff: 2

Learning Objective: 6.2 Define entropy, discussing the role of entropy in spontaneous processes

17) Predict the sign of ∆S for the following reaction.

An illustration shows conversion of a compound that has a five-carbon chain, in which C 1 is double bonded to an oxygen atom, and C 4 is bonded to a hydroxyl group, O H and a methyl group, C H 3, into a compound that has cyclopentane ring, in which a carbon atom is replaced by an oxygen atom, C 2 is bonded to a hydroxyl group, O H, and C 5 is bonded to two methyl groups.

A) positive

B) negative

C) no change

Diff: 2

Learning Objective: 6.2 Define entropy, discussing the role of entropy in spontaneous processes

18) Why is the entropy change negative for ring closures?

A) Closing a ring results in fewer molecules.

B) Closing a ring results in more molecules.

C) Closing a ring releases energy.

D) Closing a ring restricts the rotation around individual carbon-carbon bonds.

Diff: 3

Learning Objective: 6.2 Define entropy, discussing the role of entropy in spontaneous processes

19) Which of the following would you expect to have the most negative ∆S?

An illustration shows two conversions, 1 and 2 (in Roman numerals), in which two alcohols convert into heterocyclic rings. In conversion 1, the compound has a SMILES string of C=CCCCO which converts into a compound that has a SMILES string of CC1CCCO1. In conversion 2, the compound has a SMILES string of C=CCO which converts into a compound that has a SMILES string of CC1CO1. Another illustration shows two conversions, 3 and 4 (in Roman numerals), in which two alcohols convert into heterocyclic rings. In conversion 3, the compound has a SMILES string of C=CCCO which converts into a compound that has a SMILES string of CC1CCO1. In conversion 4, the compound has a SMILES string of C=CCCCCO which converts into a compound that has a SMILES string of CC1CCCCO1.

A) I

B) II

C) III

D) IV

Diff: 3

Learning Objective: 6.2 Define entropy, discussing the role of entropy in spontaneous processes

20) From the following reactions, which one(s) would you expect to have a negative ∆S?

An illustration shows two conversions, 1 and 2 (in Roman numerals), in which two compounds convert into bromo substituted rings. In conversion 1, the compound has a SMILES string of C1CCCC1 which reacts in the presence of a bromine molecule, B r 2 to form a compound that has a SMILES string of C1CC(C(C1)Br)Br. In conversion 2, the compound has a SMILES string of CC(C)(CCC=C)Br which converts into a compound that has a SMILES string of CC1(CCC(C1)Br)C. Another illustration shows two conversions, 3 and 4 (in Roman numerals), in which two cyclic compounds convert into double bonded compounds. In conversion 3, the compound has a cyclobutane ring, in which C 1 is bonded to a hydroxyl group and a chlorine atom, which converts into a compound that has a SMILES string of C1CC(=O)C1, and a molecule hydrogen chloride, H C l. In conversion 4, the compound has a SMILES string of C1CC1CBr which converts into a compound that has a SMILES string of C=CCCBr.

A) I

B) II

C) III

D) IV

E) I and II

Diff: 3

Learning Objective: 6.2 Define entropy, discussing the role of entropy in spontaneous processes

21) Predict the sign of ∆G for an exothermic reaction with an increase in entropy.

A) positive

B) negative

C) no change

D) cannot predict without additional information

Diff: 1

Learning Objective: 6.3 Discuss Gibbs free energy and endergonic and exergonic reactions

22) Predict the sign of ∆G for an endothermic reaction with an increase in entropy.

A) positive

B) negative

C) no change

D) cannot predict without additional information

Diff: 1

Learning Objective: 6.3 Discuss Gibbs free energy and endergonic and exergonic reactions

23) Predict the sign of ∆G for an exothermic reaction with a decrease in entropy.

A) positive

B) negative

C) no change

D) cannot predict without additional information

Diff: 1

Learning Objective: 6.3 Discuss Gibbs free energy and endergonic and exergonic reactions

24) Predict the sign of ∆G for an endothermic reaction with a decrease in entropy.

A) positive

B) negative

C) no change

D) cannot predict without additional information

Diff: 1

Learning Objective: 6.3 Discuss Gibbs free energy and endergonic and exergonic reactions

25) Which of the following indicates a reaction with a negative ∆G?

A) endergonic, spontaneous

B) endergonic, not spontaneous

C) exergonic, spontaneous

D) exergonic, not spontaneous

Diff: 1

Learning Objective: 6.3 Discuss Gibbs free energy and endergonic and exergonic reactions

26) Which of the following indicates a reaction with a positive ∆G?

A) endergonic, spontaneous

B) endergonic, not spontaneous

C) exergonic, spontaneous

D) exergonic, not spontaneous

Diff: 1

Learning Objective: 6.3 Discuss Gibbs free energy and endergonic and exergonic reactions

27) Does a reaction with a positive ∆G favor reactants or products?

A) Reactants

B) Products

C) Neither

D) It is impossible to tell without knowing the enthalpy

E) It is impossible to tell without know the entropy

Diff: 1

Learning Objective: 6.4 Describe the factors that affect equilibrium and that determine whether the reaction favors the reactants or products

28) Does a reaction with a value of 0 for ∆G favor reactants or products?

A) Reactants

B) Products

C) Neither

D) It is impossible to tell without knowing the enthalpy

E) It is impossible to tell without know the entropy

Diff: 1

Learning Objective: 6.4 Describe the factors that affect equilibrium and that determine whether the reaction favors the reactants or products

29) Does a reaction with a positive ∆S and a positive ∆H favor reactants or products?

A) Reactants

B) Products

C) Neither

D) It is impossible to determine without knowing the temperature

Diff: 3

Learning Objective: 6.4 Describe the factors that affect equilibrium and that determine whether the reaction favors the reactants or products

30) Does a reaction with a positive ∆S and a negative ∆?H favor reactants or products?

A) Reactants

B) Products

C) Neither

D) It is impossible to determine without knowing the temperature

Diff: 3

Learning Objective: 6.4 Describe the factors that affect equilibrium and that determine whether the reaction favors the reactants or products

31) Does a reaction with a Keq = 10 favor reactants or products?

A) Reactants

B) Products

C) Neither

D) It is impossible to determine without knowing the temperature

Diff: 1

Learning Objective: 6.4 Describe the factors that affect equilibrium and that determine whether the reaction favors the reactants or products

32) Does a reaction with a ∆H of 14 kJ/mol and a ∆S of 150 J/mol·K at 298 K favor reactants or products?

A) Reactants

B) Products

C) Neither

D) It is impossible to determine without more information

Diff: 3

Learning Objective: 6.4 Describe the factors that affect equilibrium and that determine whether the reaction favors the reactants or products

33) Does a reaction with a ∆H of 20 kJ/mol and a ∆S of 10 J/mol·K at 298 K favor reactants or products?

A) Reactants

B) Products

C) Neither

D) It is impossible to determine without more information

Diff: 3

Learning Objective: 6.4 Describe the factors that affect equilibrium and that determine whether the reaction favors the reactants or products

34) Given the following rate law, what is the order of the reaction with respect to MeI?

Rate = k[Mel][NaCN]

A) Zero

B) First

C) Second

D) Third

E) Fourth

Diff: 1

Learning Objective: 6.5 Compare kinetics and thermodynamics

35) Given the following rate law, what is the order of the reaction with respect to tert-butyl iodide?

Rate equals to k, a compound that has a SMILES string of CC(C)(C)I enclosed within square brackets.

A) Zero

B) First

C) Second

D) Third

E) Fourth

Diff: 1

Learning Objective: 6.5 Compare kinetics and thermodynamics

36) Given the following rate law, what is the order of the reaction with respect to sodium cyanide?

Rate = k[Mel][NaCN]2

A) Zero

B) First

C) Second

D) Third

E) Fourth

Diff: 1

Learning Objective: 6.5 Compare kinetics and thermodynamics

37) What is the energy of activation for the following reaction?

A graph plots free energy against reaction coordinate. The y-axis represents free energy in kilo Joule per mole, k J per mol that ranges from 10 to 40 with increment of 10, and x-axis represents reaction coordinate. The curve starts slightly away from the origin of the horizontal axis and around half of the height of the vertical axis, slopes slightly upward, and then decreases in a concave upward manner. After that, the curve ends at three-fourth length of the horizontal axis and up to one-fourth height of the vertical axis.

A) 10 kJ/mol

B) 15 kJ/mol

C) 20 kJ/mol

D) 30 kJ/mol

E) 35 kJ/mol

Diff: 1

Learning Objective: 6.5 Compare kinetics and thermodynamics

38) What is the energy of activation for the following reaction?

A graph plots free energy against reaction coordinate. The y-axis represents free energy in kilo Joule per mole, k J per mol that ranges from 5 to 20 with increment of 5, and the x-axis represents reaction coordinate. The curve starts slightly away from the origin of the horizontal axis and around one-fourth of the height of the vertical axis, slopes upward up to more than half of the height of the vertical axis, and then decreases in a concave upward manner. After that, the curve ends at three-fourth length of the horizontal axis and nearly half of the height of the vertical axis.

A) 10 kJ/mol

B) 15 kJ/mol

C) 20 kJ/mol

D) 30 kJ/mol

E) 35 kJ/mol

Diff: 1

Learning Objective: 6.5 Compare kinetics and thermodynamics

39) Based on the following energy diagram, is the reaction exothermic or endothermic?

A graph plots free energy against reaction coordinate. The y-axis represents free energy in kilo Joule per mole, k J per mol that ranges from 5 to 20 with increment of 5, and x-axis represents reaction coordinate. The curve starts slightly away from the origin of the horizontal axis and around one-fourth of the height of the vertical axis, slopes upward up to half of the height of the vertical axis, and then decreases in a concave upward manner, which is followed by another curve that slopes upward up to more than half of the height of the vertical axis, and then decreases in a concave upward manner. After that, the curve ends at three-fourth length of the horizontal axis and nearly one-fourth of the height of the vertical axis.

A) endothermic

B) exothermic

C) isothermic

D) it is impossible to tell from the information given

Diff: 3

Learning Objective: 6.5 Compare kinetics and thermodynamics

40) Based on the following energy diagram, is the reaction exothermic or endothermic?

A graph plots free energy against reaction coordinate. The y-axis represents free energy in kilo Joule per mole, k J per mol and the x-axis represents reaction coordinate. The curve starts slightly away from the origin of the horizontal axis and up to one-fourth of the height of the vertical axis, slopes upward up to half of the height of the vertical axis, and then decreases in a concave upward manner, which is followed by another curve that slopes upward slightly up to more than half of the height of the vertical axis, and then again decreases in a concave upward manner. After that, the curve ends at three-fourth length of the horizontal axis and nearly half of the height of the vertical axis.

A) endothermic

B) exothermic

C) isothermic

D) it is impossible to tell from the information given

Diff: 3

Learning Objective: 6.5 Compare kinetics and thermodynamics

41) What is the effect of a catalyst on a reaction?

A) It increases the rate.

B) It decreases the entropy.

C) It changes the equilibrium.

D) It makes the products more stable.

Diff: 1

Learning Objective: 6.5 Compare kinetics and thermodynamics

42) Which of the following describes the effect of a catalyst on a reaction?

A) It lowers the free energy of the products.

B) It makes the reactants less stable.

C) It changes the equilibrium constant.

D) It lowers the energy of activation.

Diff: 1

Learning Objective: 6.5 Compare kinetics and thermodynamics

43) Which of the following is an energy diagram for a three-step reaction?

An illustration shows four graphs, A., B., C., and D. The y-axis represents free energy in kilo Joule per mole, k J per mol and the x-axis represents reaction coordinate. In graph A., the curve starts slightly away from the origin of the horizontal axis and up to half of the height of the vertical axis, slopes upward up to three-fourth of the height of the vertical axis, and then decreases in a concave upward manner up to nearly one-fourth of the vertical axis, which is followed by another curve that slopes upward slightly up to less than half of the height of the vertical axis, and then again decreases in a concave upward manner. After that, the curve ends at nearly the complete length of the horizontal axis at up to one-fourth of the height of the vertical axis. In graph B., the curve starts slightly away from the origin of the horizontal axis and up to half of the height of the vertical axis, slopes upward up to more than half of the height of the vertical axis, and then slightly decreases in a concave upward manner, followed by second curve that slopes upward up to three-fourth height of the vertical axis, and then decreases in a concave upward manner, followed by the third curve that slopes upward up to half of the height of the vertical axis, and then decreases in a concave upward manner,. After that, the curve ends at nearly three-fourth height of the horizontal axis at up to one-fourth of the height of the vertical axis. In graph C., the curve starts slightly away from the origin of the horizontal axis and less than half of the height of the vertical axis, slopes upward up to more than half of the height of the vertical axis, and then decreases in a concave upward manner. After that, the curve ends at three-fourth length of the horizontal axis and nearly half of the height of the vertical axis. In graph D., the curve starts slightly away from the origin of the horizontal axis and up to one-fourth of the height of the vertical axis, slopes upward up to three-fourth of the height of the vertical axis, and then decreases in a concave upward manner, which is followed by another curve that slopes upward slightly up to three-fourth of the height of the vertical axis, and then again decreases in a concave upward manner. After that, the curve ends at nearly three-fourth length of the horizontal axis at up to nearly half of the height of the vertical axis.

A) A

B) B

C) C

D) D

Diff: 2

Learning Objective: 6.6 Describe an energy diagram, including what is represented by the peaks and valleys, and the Hammond postulate

44) Which of the following is an energy diagram for a two-step reaction?

An illustration shows four graphs, A., B., C., and D. The y-axis represents free energy in kilo Joule per mole, k J per mol and the x-axis represents reaction coordinate. In graph A., the curve starts slightly away from the origin of the horizontal axis and nearly half of the height of the vertical axis, slopes upward up to more than half of the height of the vertical axis, and then decreases in a concave upward manner. After that, the curve ends at three-fourth length of the horizontal axis and slightly less than half of the height of the vertical axis. In graph B., the curve starts slightly away from the origin of the horizontal axis and up to half of the height of the vertical axis, slopes upward up to three-fourth of the height of the vertical axis, and then decreases in a concave upward manner, which is followed by another curve that slopes upward slightly above half of the height of the vertical axis, and then again decreases in a concave upward manner. After that, the curve ends at nearly the complete length of the horizontal axis at up to one-fourth of the height of the vertical axis. In graph C., the curve starts slightly away from the origin of the horizontal axis and up to less than half of the height of the vertical axis, slopes upward up to three-fourth of the height of the vertical axis, and then slightly decreases in a concave upward manner, followed by second curve that slopes upward up to three-fourth height of the vertical axis, and then decreases in a concave upward manner up to less than half of the vertical axis, followed by the third curve that slopes upward up to slightly less than half of the height of the vertical axis, and then decreases in a concave upward manner,. After that, the curve ends at nearly three-fourth height of the horizontal axis at up to one-fourth of the height of the vertical axis. In graph D., the curve starts slightly away from the origin of the horizontal axis and nearly half of the height of the vertical axis, slopes upward as a straight line up to three-fourth of the height of the vertical axis and up to three-fourth of the length of the horizontal axis.

A) A

B) B

C) C

D) D

Diff: 2

Learning Objective: 6.6 Describe an energy diagram, including what is represented by the peaks and valleys, and the Hammond postulate

45) Which illustration shows an energy diagram for an endothermic reaction with two steps?

An illustration shows four graphs, A., B., C., and D. The y-axis represents free energy in kilo Joule per mole, k J per mol and the x-axis represents reaction coordinate. In graph A., the curve starts slightly away from the origin of the horizontal axis and up to half of the height of the vertical axis, slopes upward up to three-fourth of the height of the vertical axis, and then decreases in a concave upward manner up to nearly one-fourth of the vertical axis, which is followed by another curve that slopes upward slightly up to less than half of the height of the vertical axis, and then again decreases in a concave upward manner. After that, the curve ends at nearly the complete length of the horizontal axis at up to one-fourth of the height of the vertical axis. In graph B., the curve starts slightly away from the origin of the horizontal axis and up to half of the height of the vertical axis, slopes upward up to more than half of the height of the vertical axis, and then slightly decreases in a concave upward manner, followed by second curve that slopes upward up to three-fourth height of the vertical axis, and then decreases in a concave upward manner, followed by the third curve that slopes upward up to half of the height of the vertical axis, and then decreases in a concave upward manner,. After that, the curve ends at nearly three-fourth height of the horizontal axis at up to one-fourth of the height of the vertical axis. In graph C., the curve starts slightly away from the origin of the horizontal axis and less than half of the height of the vertical axis, slopes upward up to more than half of the height of the vertical axis, and then decreases in a concave upward manner. After that, the curve ends at three-fourth length of the horizontal axis and nearly half of the height of the vertical axis. In graph D., the curve starts slightly away from the origin of the horizontal axis and up to one-fourth of the height of the vertical axis, slopes upward up to three-fourth of the height of the vertical axis, and then decreases in a concave upward manner, which is followed by another curve that slopes upward slightly up to three-fourth of the height of the vertical axis, and then again decreases in a concave upward manner. After that, the curve ends at nearly three-fourth length of the horizontal axis at up to nearly half of the height of the vertical axis.

A) A

B) B

C) C

D) D

Diff: 2

Learning Objective: 6.6 Describe an energy diagram, including what is represented by the peaks and valleys, and the Hammond postulate

46) Which illustration shows an energy diagram for an exothermic reaction with three steps?

An illustration shows four graphs, A., B., C., and D. The y-axis represents free energy in kilo Joule per mole, k J per mol and the x-axis represents reaction coordinate. In graph A., the curve starts slightly away from the origin of the horizontal axis and up to half of the height of the vertical axis, slopes upward up to three-fourth of the height of the vertical axis, and then decreases in a concave upward manner up to nearly one-fourth of the vertical axis, which is followed by another curve that slopes upward slightly up to less than half of the height of the vertical axis, and then again decreases in a concave upward manner. After that, the curve ends at nearly the complete length of the horizontal axis at up to one-fourth of the height of the vertical axis. In graph B., the curve starts slightly away from the origin of the horizontal axis and up to half of the height of the vertical axis, slopes upward up to more than half of the height of the vertical axis, and then slightly decreases in a concave upward manner, followed by second curve that slopes upward up to three-fourth height of the vertical axis, and then decreases in a concave upward manner, followed by the third curve that slopes upward up to half of the height of the vertical axis, and then decreases in a concave upward manner,. After that, the curve ends at nearly three-fourth height of the horizontal axis at up to one-fourth of the height of the vertical axis. In graph C., the curve starts slightly away from the origin of the horizontal axis and less than half of the height of the vertical axis, slopes upward up to more than half of the height of the vertical axis, and then decreases in a concave upward manner. After that, the curve ends at three-fourth length of the horizontal axis and nearly half of the height of the vertical axis. In graph D., the curve starts slightly away from the origin of the horizontal axis and up to one-fourth of the height of the vertical axis, slopes upward up to three-fourth of the height of the vertical axis, and then decreases in a concave upward manner, which is followed by another curve that slopes upward slightly up to three-fourth of the height of the vertical axis, and then again decreases in a concave upward manner. After that, the curve ends at nearly three-fourth length of the horizontal axis at up to nearly half of the height of the vertical axis.

A) A

B) B

C) C

D) D

Diff: 2

Learning Objective: 6.6 Describe an energy diagram, including what is represented by the peaks and valleys, and the Hammond postulate

47) Which energy diagram below represents a concerted exothermic reaction?

An illustration shows four graphs, A., B., C., and D. The y-axis represents free energy in kilo Joule per mole, k J per mol, and the x-axis represents reaction coordinate. In graph A., the curve starts slightly away from the origin of the horizontal axis and up to half of the height of the vertical axis, slopes upward up to three-fourth of the height of the vertical axis, and then decreases in a concave upward manner, which is followed by another curve that slopes upward slightly above half of the height of the vertical axis, and then again decreases in a concave upward manner. After that, the curve ends at nearly the complete length of the horizontal axis at up to one-fourth of the height of the vertical axis. In graph B., the curve starts slightly away from the origin of the horizontal axis and up to half of the height of the vertical axis, slopes upward up to more than half of the height of the vertical axis, and then decreases in a concave upward manner, which is followed by another curve that slopes upward slightly up to three-fourth of the height of the vertical axis, and then again decreases in a concave upward manner. After that, the curve ends at nearly three-fourth length of the horizontal axis at up to more than half of the height of the vertical axis. In graph C., the curve starts slightly away from the origin of the horizontal axis and nearly half of the height of the vertical axis, slopes upward up to more than half of the height of the vertical axis, and then decreases sharply in a concave upward manner. After that, the curve ends at three-fourth length of the horizontal axis and up to one-fourth of the height of the vertical axis. In graph D., the curve starts slightly away from the origin of the horizontal axis and at one-fourth of the height of the vertical axis, slopes upward up to half of the height of the vertical axis, and then decreases in a concave upward manner. After that, the curve ends at three-fourth length of the horizontal axis and slightly less than half of the height of the vertical axis.

A) A

B) B

C) C

D) D

Diff: 2

Learning Objective: 6.6 Describe an energy diagram, including what is represented by the peaks and valleys, and the Hammond postulate

48) Which of the following energy diagrams shows a concerted endothermic reaction?

An illustration shows four graphs, A., B., C., and D. The y-axis represents free energy in kilo Joule per mole, k J per mol, and the x-axis represents reaction coordinate. In graph A., the curve starts slightly away from the origin of the horizontal axis and up to half of the height of the vertical axis, slopes upward up to three-fourth of the height of the vertical axis, and then decreases in a concave upward manner, which is followed by another curve that slopes upward slightly above half of the height of the vertical axis, and then again decreases in a concave upward manner. After that, the curve ends at nearly the complete length of the horizontal axis at up to one-fourth of the height of the vertical axis. In graph B., the curve starts slightly away from the origin of the horizontal axis and up to half of the height of the vertical axis, slopes upward up to more than half of the height of the vertical axis, and then decreases in a concave upward manner, which is followed by another curve that slopes upward slightly up to three-fourth of the height of the vertical axis, and then again decreases in a concave upward manner. After that, the curve ends at nearly three-fourth length of the horizontal axis at up to more than half of the height of the vertical axis. In graph C., the curve starts slightly away from the origin of the horizontal axis and nearly half of the height of the vertical axis, slopes upward up to more than half of the height of the vertical axis, and then decreases sharply in a concave upward manner. After that, the curve ends at three-fourth length of the horizontal axis and up to one-fourth of the height of the vertical axis. In graph D., the curve starts slightly away from the origin of the horizontal axis and at one-fourth of the height of the vertical axis, slopes upward up to half of the height of the vertical axis, and then decreases in a concave upward manner. After that, the curve ends at three-fourth length of the horizontal axis and slightly less than half of the height of the vertical axis.

A) A

B) B

C) C

D) D

Diff: 2

Learning Objective: 6.6 Describe an energy diagram, including what is represented by the peaks and valleys, and the Hammond postulate

49) Which of the following energy diagrams shows the reaction with the smallest energy of activation?

An illustration shows four graphs, A., B., C., and D. The y-axis represents free energy in kilo Joule per mole, k J per mol and the x-axis represents reaction coordinate. In graph A., the curve starts slightly away from the origin of the horizontal axis and nearly half of the height of the vertical axis, slopes upward up to more than half of the height of the vertical axis, and then decreases in a concave upward manner. After that, the curve ends at three-fourth length of the horizontal axis and slightly less than half of the height of the vertical axis. In graph B., the curve starts slightly away from the origin of the horizontal axis and up to half of the height of the vertical axis, slopes upward up to three-fourth of the height of the vertical axis, and then decreases in a concave upward manner, which is followed by another curve that slopes upward slightly above half of the height of the vertical axis, and then again decreases in a concave upward manner. After that, the curve ends at nearly the complete length of the horizontal axis at up to one-fourth of the height of the vertical axis. In graph C., the curve starts slightly away from the origin of the horizontal axis and up to less than half of the height of the vertical axis, slopes upward up to three-fourth of the height of the vertical axis, and then slightly decreases in a concave upward manner, followed by second curve that slopes upward up to three-fourth height of the vertical axis, and then decreases in a concave upward manner up to less than half of the vertical axis, followed by the third curve that slopes upward up to slightly less than half of the height of the vertical axis, and then decreases in a concave upward manner,. After that, the curve ends at nearly three-fourth height of the horizontal axis at up to one-fourth of the height of the vertical axis. In graph D., the curve starts slightly away from the origin of the horizontal axis and nearly half of the height of the vertical axis, slopes upward as a straight line up to three-fourth of the height of the vertical axis and up to three-fourth of the length of the horizontal axis.

A) A

B) B

C) C

D) D

Diff: 2

Learning Objective: 6.6 Describe an energy diagram, including what is represented by the peaks and valleys, and the Hammond postulate

50) What is a transition state?

A) An isolable intermediate in a reaction.

B) The starting materials of the reaction.

C) A local maximum on the energy diagram.

D) A low-energy point between the starting materials and the product.

Diff: 1

Learning Objective: 6.6 Describe an energy diagram, including what is represented by the peaks and valleys, and the Hammond postulate

51) What is an intermediate?

A) A local maximum on the energy diagram.

B) A point on the reaction pathway that has a discrete minima.

C) A point half-way between the starting materials and products.

D) The highest energy compound on an energy diagram.

Diff: 1

Learning Objective: 6.6 Describe an energy diagram, including what is represented by the peaks and valleys, and the Hammond postulate

52) Which of the following energy diagrams describes a reaction with one transition state?

An illustration shows four graphs, A., B., C., and D. The y-axis represents free energy in kilo Joule per mole, k J per mol and the x-axis represents reaction coordinate. In graph A., the curve starts slightly away from the origin of the horizontal axis and nearly half of the height of the vertical axis, slopes upward up to more than half of the height of the vertical axis, and then decreases in a concave upward manner. After that, the curve ends at three-fourth length of the horizontal axis and slightly less than half of the height of the vertical axis. In graph B., the curve starts slightly away from the origin of the horizontal axis and up to half of the height of the vertical axis, slopes upward up to three-fourth of the height of the vertical axis, and then decreases in a concave upward manner, which is followed by another curve that slopes upward slightly above half of the height of the vertical axis, and then again decreases in a concave upward manner. After that, the curve ends at nearly the complete length of the horizontal axis at up to one-fourth of the height of the vertical axis. In graph C., the curve starts slightly away from the origin of the horizontal axis and up to less than half of the height of the vertical axis, slopes upward up to three-fourth of the height of the vertical axis, and then slightly decreases in a concave upward manner, followed by second curve that slopes upward up to three-fourth height of the vertical axis, and then decreases in a concave upward manner up to less than half of the vertical axis, followed by the third curve that slopes upward up to slightly less than half of the height of the vertical axis, and then decreases in a concave upward manner,. After that, the curve ends at nearly three-fourth height of the horizontal axis at up to one-fourth of the height of the vertical axis. In graph D., the curve starts slightly away from the origin of the horizontal axis and nearly half of the height of the vertical axis, slopes upward as a straight line up to three-fourth of the height of the vertical axis and up to three-fourth of the length of the horizontal axis.

A) A

B) B

C) C

D) D

Diff: 2

Learning Objective: 6.6 Describe an energy diagram, including what is represented by the peaks and valleys, and the Hammond postulate

53) Which of the following energy diagrams describes a reaction with one intermediate?

An illustration shows four graphs, A., B., C., and D. The y-axis represents free energy in kilo Joule per mole, k J per mol and the x-axis represents reaction coordinate. In graph A., the curve starts slightly away from the origin of the horizontal axis and nearly half of the height of the vertical axis, slopes upward up to more than half of the height of the vertical axis, and then decreases in a concave upward manner. After that, the curve ends at three-fourth length of the horizontal axis and slightly less than half of the height of the vertical axis. In graph B., the curve starts slightly away from the origin of the horizontal axis and up to half of the height of the vertical axis, slopes upward up to more than half of the height of the vertical axis, and then decreases in a concave upward manner, which is followed by another curve that slopes upward slightly up to half of the height of the vertical axis, and then again decreases in a concave upward manner. After that, the curve ends at nearly the complete length of the horizontal axis at up to one-fourth of the height of the vertical axis. In graph C., the curve starts slightly away from the origin of the horizontal axis and up to less than half of the height of the vertical axis, slopes upward up to three-fourth of the height of the vertical axis, and then slightly decreases in a concave upward manner, followed by second curve that slopes upward up to three-fourth height of the vertical axis, and then decreases in a concave upward manner up to less than half of the vertical axis, followed by the third curve that slopes upward up to slightly less than half of the height of the vertical axis, and then decreases in a concave upward manner. After that, the curve ends at nearly three-fourth height of the horizontal axis at up to one-fourth of the height of the vertical axis. In graph D., the curve starts slightly away from the origin of the horizontal axis and nearly half of the height of the vertical axis, slopes upward as a straight line up to three-fourth of the height of the vertical axis and up to three-fourth of the length of the horizontal axis.

A) A

B) B

C) C

D) D

Diff: 2

Learning Objective: 6.6 Describe an energy diagram, including what is represented by the peaks and valleys, and the Hammond postulate

54) Which arrow identifies the nucleophilic site in the molecule shown?

The bond-line structure of a compound has a SMILES string of C1CCC(=O)CC1. An arrow, labeled, a points to the oxygen atom. An arrow, labeled, b points to C 1. An arrow, labeled, c points to C 2. An arrow, labeled, d points to C 3. An arrow, labeled, e points to C 4.

A) a

B) b

C) c

D) d

E) e

Diff: 1

Learning Objective: 6.7 Compare nucleophiles, electrophiles, and carbocations

55) Which arrow identifies the nucleophilic site in the molecule shown?

The bond-line structure of a compound has a SMILES string of C1CCOC1. An arrow, labeled, a points to C 1. An arrow, labeled, b points to C 2. An arrow, labeled, c points to C 3. An arrow, labeled, d points to C 4. An arrow, labeled, e points to the oxygen atom.

A) a

B) b

C) c

D) d

E) e

Diff: 1

Learning Objective: 6.7 Compare nucleophiles, electrophiles, and carbocations

56) Which arrow(s) identifies the nucleophilic site(s) in the molecule shown?

The bond-line structure of a compound has a SMILES string of CCCNC(=O)C. An arrow, labeled, a points to C 1 of the propyl chain bonded to amide group. An arrow, labeled, b points to the nitrogen atom of the amide group. An arrow, labeled, c points to the oxygen atom double bonded to the carbonyl carbon. An arrow, labeled, d points to the carbonyl carbon atom. An arrow, labeled, e points to C 2 bonded to the carbonyl carbon atom.

A) a and b

B) b and c

C) d

D) e

E) a and e

Diff: 2

Learning Objective: 6.7 Compare nucleophiles, electrophiles, and carbocations

57) Which arrow(s) identifies the nucleophilic center(s) in the molecule shown?

The bond-line structure of a compound has a two-carbon chain, in which C 1 is double bonded to C 2 that carries a negative charge. An arrow, labeled, a points to C 1. An arrow, labeled, b points to C 2. An arrow, labeled, c points to the double bond.

A) a

B) b

C) c

D) a and b

E) b and c

Diff: 1

Learning Objective: 6.7 Compare nucleophiles, electrophiles, and carbocations

58) Identify the nucleophilic atom in Me3P.

A) P

B) C

C) H

D) Me

Diff: 1

Learning Objective: 6.7 Compare nucleophiles, electrophiles, and carbocations

59) Identify the electrophilic site in the molecule shown.

The bond-line structure of a compound has a SMILES string of C1CCC(=O)CC1. An arrow, labeled, a points to the oxygen atom. An arrow, labeled, b points to C 1. An arrow, labeled, c points to C 2. An arrow, labeled, d points to C 3. An arrow, labeled, e points to C 4.

A) a

B) b

C) c

D) d

E) e

Diff: 1

Learning Objective: 6.7 Compare nucleophiles, electrophiles, and carbocations

60) Identify the electrophilic site in the molecule shown.

The bond-line structure of a compound has a SMILES string of CCC(C)Br. An arrow, labeled, a points to C 1. An arrow, labeled, b points to C 2. An arrow, labeled, c points to the bromine atom. An arrow, labeled, d points to C 3. An arrow, labeled, e points to C 4.

A) a

B) b

C) c

D) d

E) e

Diff: 1

Learning Objective: 6.7 Compare nucleophiles, electrophiles, and carbocations

61) Identify the electrophilic site in the molecule shown.

The bond-line structure of a compound has a SMILES string of c1ccccc1, in which C 1 carries a positive charge. An arrow, labeled, a points to the positive charge. An arrow, labeled, b points to C 2. An arrow, labeled, c points to C 3. An arrow, labeled, d points to C 4. An arrow, labeled, e points to C 5.

A) a

B) b

C) c

D) d

E) e

Diff: 1

Learning Objective: 6.7 Compare nucleophiles, electrophiles, and carbocations

62) Identify the electrophilic site in the molecule shown.

The bond-line structure of a compound has a four-carbon chain, in which C 2 and C 3 each are single bonded to a methyl group and an oxygen atom. Each oxygen atom is bonded to a common boron atom, which is further bonded to a methyl group.

A) C

B) O

C) B

D) no electrophilic site

Diff: 2

Learning Objective: 6.7 Compare nucleophiles, electrophiles, and carbocations

63) Which of the structures shown cannot be a nucleophile?

An illustration shows four chemical structures, labeled, 1, 2, 3, and 4. Structure 1 has a five-carbon chain, in which C 2 carries a positive charge. Structure 2 has a SMILES string of CC(C)O. Structure 3 has a SMILES string of CC(=C)C. Structure 4 has a bromine anion, B r superscript minus.

A) I

B) II

C) III

D) IV

Diff: 1

Learning Objective: 6.7 Compare nucleophiles, electrophiles, and carbocations

64) Which of the structures shown cannot be an electrophile?

An illustration shows four chemical structures, labeled, 1, 2, 3, and 4. Structure 1 has a five-carbon chain, in which C 2 carries a positive charge. Structure 2 has a SMILES string of CC(C)Br. Structure 3 has a SMILES string of CC(=O)C. Structure 4 has a sodium cation, N a superscript plus.

A) I

B) II

C) III

D) IV

Diff: 1

Learning Objective: 6.7 Compare nucleophiles, electrophiles, and carbocations

65) Which of the choices shown is hydride?

A) H+

B) H

C) H−

D) H2

Diff: 1

Learning Objective: 6.8 List the four characteristic arrow pushing patterns and discuss the events of carbocation rearrangement

66) Which of the structures shown is the most stable cation?

An illustration shows four chemical structures, labeled, 1, 2, 3, and 4 (in Roman numerals). Structure 1 has a five-carbon chain, in which C 2 carries a positive charge. Structure 2 has a SMILES string of C1CCCC[CH+]1. Structure III has a SMILES string of C[C+](C)C. Structure IV has a SMILES string of CCC[CH2+].

A) I

B) II

C) III

D) IV

Diff: 1

Learning Objective: 6.8 List the four characteristic arrow pushing patterns and discuss the events of carbocation rearrangement

67) Which pattern of arrow pushing is involved in the reaction step shown?

In a reaction, the reactant has a SMILES string of CC(=O)C, in which the oxygen atom carries two lone pairs of electrons that reacts with hydrogen ion, H superscript plus. A curved arrow points from the lone pair of electrons toward the hydrogen ion. A cation is formed that has a three-carbon chain, in which C 2 is double bonded to an oxygen atom that carries a lone pair of electrons and positive charge, which is further bonded to a hydrogen atom.

A) proton transfer

B) loss of leaving group

C) nucleophilic attack

D) rearrangement

Diff: 1

Learning Objective: 6.8 List the four characteristic arrow pushing patterns and discuss the events of carbocation rearrangement

68) Indicate which pattern of arrow pushing is involved in the reaction step shown.

An illustration shows a cation that has a benzene ring, in which C 1 is bonded to an oxygen atom having a positive charge, and further bonded to two hydrogen atoms. A curved arrow points from the bond between C 1 and the oxygen atom toward the same oxygen atom having a positive charge, to form another cation that has a benzene ring, in which C 1 carries a positive charge.

A) proton transfer

B) loss of leaving group

C) nucleophilic attack

D) rearrangement

Diff: 1

Learning Objective: 6.8 List the four characteristic arrow pushing patterns and discuss the events of carbocation rearrangement

69) Indicate which pattern of arrow pushing it is involved in the reaction step shown.

In a reaction, the reactant has a SMILES string of c1ccc(cc1)O that reacts with a hydrogen ion, H superscript plus. A curved arrow points from the oxygen atom of the hydroxyl group toward the hydrogen ion. A cation is formed that has a benzene ring , in which C 1 is bonded to an oxygen atom that carries a positive charge, and is further bonded to two hydrogen atoms.

A) proton transfer

B) loss of leaving group

C) nucleophilic attack

D) rearrangement

Diff: 1

Learning Objective: 6.8 List the four characteristic arrow pushing patterns and discuss the events of carbocation rearrangement

70) Indicate which pattern of arrow pushing it is involved in the reaction step shown.

An illustration shows a cation that has a four-carbon chain, in which C 2 is bonded to a hydrogen atom and a methyl group, and C 3 carries a positive charge. A curved arrow points from the bond between C 2 and the hydrogen atom toward C 3 to form another cation that has a four-carbon chain, in which C 2 has a positive charge, and is bonded to a methyl group.

A) proton transfer

B) loss of leaving group

C) nucleophilic attack

D) rearrangement

Diff: 1

Learning Objective: 6.8 List the four characteristic arrow pushing patterns and discuss the events of carbocation rearrangement

71) Indicate which pattern of arrow pushing it is involved in the reaction step shown.

In a reaction, a cation that has a benzene ring , in which C 1 carries a positive charge, reacts with a bromine ion, B r superscript minus. An arrow points from the negative charge on the bromine ion toward C 1 that carries a positive charge. A compound that has a SMILES string of c1ccc(cc1)Br is formed.

A) proton transfer

B) loss of leaving group

C) nucleophilic attack

D) rearrangement

Diff: 1

Learning Objective: 6.8 List the four characteristic arrow pushing patterns and discuss the events of carbocation rearrangement

72) Melphalan, a drug used in chemotherapy, reacts with itself in the body before binding with its target, as illustrated in the mechanism below. Which two patterns of arrow pushing are seen in this reaction?

An illustration shows conversion of melphalan into a salt. Melphalan has a SMILES string of c1cc(ccc1CC(C(=O)O)N)N(CCCl)CCCl, in which the nitrogen atom at C 4 has a lone pair of electrons. The salt has a similar structure as melphalan except an ethyl chain bonded to the nitrogen atom forms a cyclopropane ring with the nitrogen atom having a positive charge, replacing one of the carbon atoms of the same ring, and a chlorine ion, C l superscript minus.

Diff: 2

Learning Objective: 6.8 List the four characteristic arrow pushing patterns and discuss the events of carbocation rearrangement

73) The reaction shown has three mechanistic steps. Which choice shows the curved arrows necessary to complete the mechanism?

An illustration shows three reaction mechanisms. Mechanism 1: The reactant that has a SMILES string of CCC(C)(C(C)C)O with two lone pairs of electrons on the oxygen reacts with hydrogen bromide to form a product that has a similar structure as that of the reactant, except that the hydroxyl group is replaced by a bromine atom. A curved arrow from the hydrogen atom of hydrogen bromide points toward the hydroxyl hydrogen. In the first intermediate, C 3 is bonded to O H 2 with a positive charge on the oxygen atom in place of the hydroxyl group. Second curved arrow from bromine atom of hydrogen bromide points toward the O H 2 group. The second intermediate has a 5-carbon chain. C 2 and C 3 are each bonded to a methyl group. C 3 carries a positive charge. A bromide ion attacks C 3. A hydronium ion departs the reaction. Mechanism 2: A curved arrow from one of the lone pairs of electrons on the hydroxyl group points toward the hydrogen atom of hydrogen bromide. The first intermediate has a SMILES string of CCC(C)(C)C(C)C. H O B r departs the reaction. The second intermediate has a 5-carbon chain. C 2 and C 3 are each bonded to a methyl group. C 3 carries a positive charge. A bromide ion attacks C 3. A water molecule departs the reaction. A curved arrow from a bromide ion points toward C 3. Mechanism 3: A curved arrow from one of the lone pairs of electrons on the hydroxyl oxygen of reactant points toward the hydrogen atom of hydrogen bromide. Another curved arrow from the single bond between H and B r points toward the bromine atom. In the first intermediate, C 3 is bonded to O H 2 with a positive charge on the oxygen atom in place of the hydroxyl group. Hydrogen bromide departs the reaction. Second curved arrow from the single bond of O H 2 group points toward a lone pair of electrons on the oxygen. The second intermediate has a 5-carbon chain. C 2 and C 3 are each bonded to a methyl group. C 3 carries a positive charge. A bromide ion attacks C 3. A bromide ion attacks C 3. A water molecule departs the reaction.

A) I

B) II

C) III

D) The reaction will not occur

Diff: 2

Learning Objective: 6.8 List the four characteristic arrow pushing patterns and discuss the events of carbocation rearrangement

74) What is wrong with the mechanism shown?

In a reaction, a cation has a four-carbon chain, in which C 2 is bonded to an oxygen atom that carries a positive charge and is bonded to two hydrogen atoms. The cation reacts with a bromine anion, B r superscript minus to yield a bromo substituted product. An arrow points from the negative charge on the bromine ion toward C 2 of the cation. The product has a SMILES string of CCC(C)Br.

A) There is no leaving group, so there should be no arrows.

B) The arrow should be removing a proton from the H2O group.

C) An arrow is also needed to indicate the loss of the leaving group.

D) The arrow is backwards.

Diff: 2

Learning Objective: 6.8 List the four characteristic arrow pushing patterns and discuss the events of carbocation rearrangement

75) What is wrong with the mechanism shown?

In a reaction, a cation has a four-carbon chain, in which C 2 is bonded to an oxygen atom that carries a positive charge and is bonded to two hydrogen atoms. The cation reacts with a bromine anion, B r superscript minus to yield a bromo substituted product. An arrow points from C 2 toward the bromine anion. Another curved arrow points from the bond between C 2 and the oxygen atom toward the same oxygen atom having a positive charge. The product has a SMILES string of CCC(C)Br.

A) There is no leaving group, so there should be no arrows.

B) The arrow should be removing a proton from the H2O group.

C) An arrow is also needed to indicate the loss of the leaving group.

D) The arrow indicating the formation of the C-Br bond (nucleophilic attack) should start at the bromide anion.

Diff: 2

Learning Objective: 6.8 List the four characteristic arrow pushing patterns and discuss the events of carbocation rearrangement

76) Which of the mechanistic steps shown represents a nucleophilic attack?

An illustration shows four reactions, 1, 2, 3, and 4 (in Roman numerals), in which a cation reacts with a bromine anion to form a bromo substituted product. In reaction 1, the cation has a four-carbon chain, in which C 2 is bonded to an oxygen atom that carries a positive charge and is bonded to two hydrogen atoms. A curved arrow points from the bromine anion toward C 2. The product has a SMILES string of CCC(C)Br. In reaction 2, the cation has a four-carbon chain, in which C 2 is bonded to an oxygen atom that carries a positive charge and is bonded to two hydrogen atoms. A curved arrow points from the bromine anion toward C 2. Another curved arow points from the bond between C 2 and the oxygen atom toward the same oxygen atom having a positive charge. The product has a SMILES string of CCC(C)Br. In reaction 3, the cation has a four-carbon chain, in which C 2 is bonded to an oxygen atom that carries a positive charge and is bonded to two hydrogen atoms. A curved arrow points from C 2 toward the bromine anion. Another curved arow points from the bond between C 2 and the oxygen atom toward the same oxygen atom having a positive charge. The product has a SMILES string of CCC(C)Br. In reaction 4, the cation has a four-carbon chain, in which C 2 is bonded to an oxygen atom that carries a positive charge and is bonded to two hydrogen atoms. A curved arrow points from C 2 toward the bromine anion. The product has a SMILES string of CCC(C)Br.

A) I

B) II

C) III

D) IV

Diff: 2

Learning Objective: 6.8 List the four characteristic arrow pushing patterns and discuss the events of carbocation rearrangement

77) Which of the mechanistic steps shown represents the loss of a leaving group?

An illustration shows four interconversions, 1, 2, 3, and 4 (in Roman numerals). In conversion 1, the compound has a SMILES string of c1ccc(cc1)O that reacts with hydrogen ion, H superscript plus. A curved arrow points from the oxygen atom of the hydroxyl group toward the hydrogen ion. A cation is formed that has a cyclohexane ring, in which C 1 is bonded to an oxygen atom that carries a positive charge, and is bonded to two hydrogen atoms. In conversion 2, the cation has a SMILES string of C1CCCC[CH+]1 that reacts with bromine ion, B r superscript minus. A curved arrow points from the bromine ion toward C 1 that carries a positive charge. The compound has a SMILES string of CC1CCCCC1. In conversion 3, a cation has a cyclohexane ring, in which C 1 is bonded to an oxygen atom that carries a positive charge, and is bonded to two hydrogen atoms that converts into a cation that has a SMILES string of C1CCCC[CH+]1. In conversion 4, a cation has a four-carbon chain, in which C 2 is bonded to a methyl group and a hydrogen atom, and C 3 carries a positive charge. An arrow points from the bond between C 2 and the hydrogen atom toward C 3. Another carbocation is formed that has a SMILES string of CC[C+](C)C.

A) I

B) II

C) III

D) IV

Diff: 2

Learning Objective: 6.8 List the four characteristic arrow pushing patterns and discuss the events of carbocation rearrangement

78) Identify the sequence of curved arrows (electron movement) in the steps of the reaction shown.

An illustration shows two-step reaction, in which a ketone converts into an alcohol. Step 1: The reactant has a SMILES string of CC(=O)C, in which the oxygen atom has two lone pairs of electrons that reacts with a hydrogen ion, H superscript plus to form an intermediate cation. A curved arrow points from a lone pair of electrons on the oxygen atom of the reactant toward the hydrogen ion. The intermediate cation has a three-carbon chain, in which C 2 is double bonded to an oxygen atom that carries a lone pair of electrons and a positive charge and is further bonded to a hydrogen atom. C 3 is bonded to a hydrogen atom. Step 2: In the presence of a boron atom that carries a lone pair of electrons, the product is formed. A curved arrow points from the lone pair on the boron atom toward the hydrogen atom bonded at C 3. Another curved arrow points from the bond between C 3 and the hydrogen atom toward the adjacent bond between C 2 and C 3. The third curved arrow points from the double bond between C 2 and the oxygen atom toward the same oxygen atom with a positive charge. The product has a SMILES string of CC(=C)O.

A) proton transfer, proton transfer

B) proton transfer, loss of leaving group

C) nucleophilic attack, proton transfer

D) proton transfer, nucleophilic attack

Diff: 2

Learning Objective: 6.9 Describe what happens in a concerted process, including the kinds of arrow-pushing patterns that can be found

79) Identify the sequence of curved arrows (electron movement) in the steps of the reaction shown.

An illustration shows three-step reaction, in which a ketone converts into an alcohol. Step 1: The reactant has a SMILES string of CC(=O)C, in which the oxygen atom has two lone pairs of electrons that reacts with a hydrogen ion, H superscript plus to form an intermediate cation. A curved arrow points from a lone pair of electrons on the oxygen atom of the reactant toward the hydrogen ion. The intermediate cation has a three-carbon chain, in which C 2 is double bonded to an oxygen atom that carries a lone pair of electrons and a positive charge and is further bonded to a hydrogen atom. Step 2: In the presence of methanol, M e O H, in which the oxygen atom carries two lone pairs of electrons, another intermediate is formed. A curved arrow points from the lone pair on the oxygen atom of methanol toward C 2. Another curved arrow points from the double bond between C 2 and the oxygen atom toward the same oxygen atom with a positive charge. The second intermediate cation has a three-carbon chain. C 2 is bonded to a hydroxyl group, and an oxygen atom having a positive charge which is further bonded to a hydrogen atom and a methyl group. Step 3: The product has a SMILES string of CC(=C)O. In the presence of methanol, M e O H, in which the oxygen atom carries two lone pairs of electrons, another intermediate is formed. A curved arrow points from the lone pair on the oxygen atom of methanol toward the hydrogen atom bonded to the oxygen atom having a positive charge bonded at C 2. Another curved arrow points from the bond between the hydrogen atom and the oxygen atom toward the same oxygen atom with a positive charge. The product has a SMILES string of OC(OC)(C)C.

A) proton transfer, proton transfer, nucleophilic Attack

B) proton transfer, loss of leaving group

C) nucleophilic attack, proton transfer, loss of leaving group

D) proton transfer, nucleophilic attack, proton transfer

Diff: 3

Learning Objective: 6.9 Describe what happens in a concerted process, including the kinds of arrow-pushing patterns that can be found

80) Identify the sequence of curved arrows (electron movement) in the steps of the reaction shown.

An illustration shows two-step reaction, in which an alkene converts into a chloro substituted alkane. Step 1: The reactant has a SMILES string of CC(=C)C that reacts with hydrogen chloride, H bonded to C l to form an intermediate cation. A curved arrow points from the double bond toward the hydrogen atom. Another curved arrow points from the bond between the hydrogen atom and the chlorine atom toward the same chlorine atom. The intermediate cation has a SMILES string of C[C+](C)C. Step 2: In the presence of chlorine ion, C l superscript minus, the intermediate cation forms a product. A curved arrow points from the chlorine ion toward the positive charge on the intermediate cation. The product has a SMILES string of CC(C)(C)Cl.

A) proton transfer, proton transfer

B) proton transfer, loss of leaving group

C) nucleophilic attack, proton transfer

D) proton transfer, nucleophilic attack

Diff: 3

Learning Objective: 6.9 Describe what happens in a concerted process, including the kinds of arrow-pushing patterns that can be found

81) What pattern of curved arrow pushing is the second step of this reaction?

A) proton transfer

B) loss of leaving group

C) nucleophilic attack

D) rearrangement

Diff: 3

Learning Objective: 6.9 Describe what happens in a concerted process, including the kinds of arrow-pushing patterns that can be found

82) What pattern of curved arrow pushing is the fourth step of this reaction?

A) proton transfer

B) loss of leaving group

C) nucleophilic attack

D) rearrangement

Diff: 3

Learning Objective: 6.9 Describe what happens in a concerted process, including the kinds of arrow-pushing patterns that can be found

83) What pattern of curved arrow pushing is the second step of this reaction?

An illustration shows two-step reaction, in which an alkene converts into a chloro substituted alkane. Step 1: The reactant has a SMILES string of CC(=C)C that reacts with hydrogen chloride, H bonded to C l to form an intermediate cation. A curved arrow points from the double bond toward the hydrogen atom. Another curved arrow points from the bond between the hydrogen atom and the chlorine atom toward the same chlorine atom. The intermediate cation has a SMILES string of C[C+](C)C. Step 2: In the presence of chlorine ion, C l superscript minus, the intermediate cation forms a product. A curved arrow points from the chlorine ion toward the positive charge on the intermediate cation. The product has a SMILES string of CC(C)(C)Cl.

A) proton transfer

B) loss of leaving group

C) nucleophilic attack

D) rearrangement

Diff: 2

Learning Objective: 6.9 Describe what happens in a concerted process, including the kinds of arrow-pushing patterns that can be found

84) Which of the following mechanisms correctly uses curved arrows to show the movement of electrons?

An illustration shows five multi-step reactions, 1, 2, 3, 4, and 5 (in Roman numerals) in which a dihydroxy compound converts into a ketone. The reactant has two central carbon atoms bonded to each other, in which C 1 and C 2 are each bonded to a hydroxyl group, O H, wedge and dash bonded to a methyl group. In reaction 1, the reactant reacts with a hydrogen ion, H superscript plus to form an intermediate cation. A curved arrow points from one of the oxygen atoms of the hydroxyl group at C 1 toward the hydrogen ion. The intermediate cation has a similar structure as the reactant except the oxygen atom of the hydroxyl group bonded to C 1 carries a positive charge, and is bonded to two hydrogen atoms. A curved arrow points from the bond between C 1 and the oxygen atom toward the same oxygen atom having a positive charge. A second intermediate cation is formed that has a similar structure as the reactant except the hydroxyl group at C 1 is eliminated and C 1 carries a positive charge. A curved arrow points from the wedge bond between C 2 and the methyl group toward the positive charge at C 1. A third intermediate cation is formed that has a similar structure as the reactant except the hydroxyl group at C 1 is replaced by a methyl group, the wedge bonded methyl group is eliminated, and C 2 carries a positive charge. A curved arrow points from the oxygen atom of the hydroxyl group bonded at C 2 toward the bond between C 2 and the oxygen atom. The fourth intermediate cation has a similar structure as the reactant except the hydroxyl group at C 1 is replaced by a methyl group, the wedge bonded methyl group at C 2 is eliminated, and C 2 is double bonded to an oxygen atom that carries a positive charge, and is further bonded to a hydrogen atom. A curved arrow points from the bond between the hydrogen atom and the oxygen atom bonded at C 2 toward the same oxygen atom that carries a positive charge. The product has two central carbon atoms bonded to each other, in which C 1 double bonded to an oxygen atom, and dash bonded to a methyl group, C 2 is single bonded, wedge bonded, and dash bonded to a methyl group. In reaction 2, the reactant reacts with a hydrogen ion, H superscript plus to form an intermediate cation that has a similar structure as the reactant except the dash bonded methyl group is eliminated from C 1, and C 1 carries a positive charge. The product has two central carbon atoms bonded to each other, in which C 1 is double bonded to an oxygen atom, and wedge bonded to a methyl group, C 2 is bonded to a hydroxyl group, O H, wedge bonded, and dash bonded to a methyl group. In reaction 3, the reactant reacts with a hydrogen ion, H superscript plus to form an intermediate cation. A curved arrow points from one of the oxygen atoms of the hydroxyl group at C 1 toward the hydrogen ion. The intermediate cation has a similar structure as the reactant except the oxygen atom of the hydroxyl group bonded to C 1 carries a positive charge, and is bonded to two hydrogen atoms. A curved arrow points from the oxygen atom having positive charge toward the bond between the same oxygen atom and C 1. A second intermediate is formed that has a similar structure as the reactant except C 1 carries a positive charge, and is double bonded to an oxygen atom. The product has two central carbon atoms bonded to each other, in which C 1 is double bonded to an oxygen atom, and dash bonded to a methyl group, C 2 is bonded to a hydroxyl group, O H, wedge bonded, and dash bonded to a methyl group.

In reaction 4, the reactant reacts with a hydrogen ion, H superscript plus to form an intermediate cation. A curved arrow points from one of the oxygen atoms of the hydroxyl group at C 1 toward the hydrogen ion. The intermediate cation has a similar structure as the reactant except the oxygen atom of the hydroxyl group bonded to C 1 carries a positive charge, and is bonded to two hydrogen atoms. A curved arrow points from the bond between C 1 and the oxygen atom toward the same oxygen atom having a positive charge. A second intermediate cation is formed that has a similar structure as the reactant except the hydroxyl group at C 1 is eliminated and C 1 carries a positive charge. A curved arrow points from the wedge bond between C 2 and the methyl group toward the positive charge at C 1. A third intermediate cation is formed that has a similar structure as the reactant except the hydroxyl group at C 1 is replaced by a methyl group, the wedge bonded methyl group is eliminated, and C 2 carries a positive charge. A curved arrow points from the dash bond between C 2 and the methyl group toward the positive charge at C 2. A compound is formed that has a similar structure as the reactant except C 1 is double bonded to C 2, the hydroxyl group at C 1 is replaced by a methyl group, the wedge and dash bonded methyl groups at C 2 are eliminated. A curved arrow points from the double bond between C 1 and C 2 toward the bond between C 1 and the methyl group. The product has two central carbon atoms bonded to each other, in which C 1 double bonded to an oxygen atom, and dash bonded to a methyl group, C 2 is single bonded, wedge bonded, and dash bonded to a methyl group. In reaction 5, the reactant reacts with a hydrogen ion, H superscript plus to form an intermediate cation. A curved arrow points from one of the oxygen atoms of the hydroxyl group at C 1 toward the hydrogen ion. The intermediate cation has a similar structure as the reactant except the oxygen atom of the hydroxyl group bonded to C 1 carries a positive charge, and is bonded to two hydrogen atoms. A curved arrow points from the bond between C 1 and the oxygen atom toward the same oxygen atom having a positive charge. Another curved arrow points from C 2 toward the oxygen atom of the hydroxyl group bonded to C 2. A second intermediate cation is formed that has a similar structure as the reactant except the hydroxyl group at C 1 is eliminated and C 1 carries a positive charge, the oxygen atom is double bonded to C 2, which is further bonded to two hydrogen atoms. A curved arrow points from the wedge bond between C 2 and the methyl group toward the positive charge at C 1. A compound is formed that has a similar structure as the reactant except the hydroxyl group at C 1 is replaced by a methyl group, the wedge bonded methyl group is eliminated, and an oxygen atom is bonded to C 2 which is further bonded to two hydrogen atoms. A curved arrow points from the oxygen atom bonded to C 2 toward the bond between the same oxygen atom and C 2. The product has two central carbon atoms bonded to each other, in which C 1 double bonded to an oxygen atom, and dash bonded to a methyl group, C 2 is single bonded, wedge bonded, and dash bonded to a methyl group.

A) I

B) II

C) III

D) IV

E) V

Diff: 3

Learning Objective: 6.10 Describe the proper placement of the head and tail of a curved arrow

85) Which of the following mechanisms correctly uses curved arrows to show the movement of electrons?

An illustration shows five multi-step reactions, 1, 2, 3, 4, and 5 (in Roman numerals) of a hydroxyl compound. The reactant has a SMILES string of CCC(C)O, in which the oxygen atom of the hydroxyl group has a lone pair of electrons. In reaction 1, the reactant reacts with a hydrogen ion, H superscript plus to form an intermediate cation. A curved arrow points from the bond between C 1 and C 2 toward the hydrogen ion. The intermediate cation has a four-carbon chain, in which C 2 is bonded to an oxygen atom that carries a lone pair of electrons and a positive charge, and is further bonded to two hydrogen atoms. A curved arrow points from the bond between C 2 and the oxygen atom toward the same oxygen atom having a positive charge. Another intermediate cation is formed that has a four-carbon chain, in which C 2 is bonded to a methyl group, and C 3 carries a positive charge. In the presence of a boron atom that carries a lone pair of electrons, a product is formed that has a similar structure as the previous intermediate cation except C 3 is bonded to a boron atom. In reaction 2, the reactant reacts with a hydrogen ion, H superscript plus to form an intermediate cation. A curved arrow points from the oxygen atom of the hydroxyl group toward the hydrogen ion. The intermediate cation has a four-carbon chain, in which C 2 is bonded to an oxygen atom that carries a lone pair of electrons and a positive charge, and is further bonded to two hydrogen atoms. A curved arrow points from the bond between C 2 and the oxygen atom toward the same oxygen atom having a positive charge. Another intermediate cation is formed that has a four-carbon chain, in which C 2 is bonded to a hydrogen atom, and C 3 carries a positive charge. In the presence of a boron atom that carries a lone pair of electrons, a product is formed. A curved arrow points from the boron atom toward the hydrogen atom bonded at C 2. Another curved arrow points from the bond between C 2 and the hydrogen atom toward the adjacent bond between C 2 and C 3. The product has a SMILES string of C/C=C/C. In reaction 3, the reactant reacts with a hydrogen ion, H superscript plus to form an intermediate cation. A curved arrow points from the oxygen atom of the hydroxyl group bonded to C 2 toward the hydrogen ion. The intermediate cation has a four-carbon chain, in which C 2 is bonded to an oxygen atom that carries a lone pair of electrons and a positive charge, and is further bonded to two hydrogen atoms. A curved arrow points from the bond between C 2 and the oxygen atom toward the same oxygen atom having a positive charge. A product that has a SMILES string of CCC(=O)C is formed. In reaction 4, the reactant reacts with a hydrogen ion, H superscript plus to form an intermediate cation. A curved arrow points from the oxygen atom of the hydroxyl group bonded to C 2 toward the hydrogen ion. The intermediate cation has a four-carbon chain, in which C 2 is bonded to an oxygen atom that carries a lone pair of electrons and a positive charge, and is further bonded to two hydrogen atoms. A curved arrow from the oxygen atom bonded to C 2 points outward. A product that has a SMILES string of CC(C)C(C)C is formed, which is followed by a forward arrow. In reaction 5, the reactant converts into a product. An arrow points toward the bond between C 2 and the oxygen atom of the hydroxyl group. The product has a SMILES string of CCC(=O)C is formed.

A) I

B) II

C) III

D) IV

E) V

Diff: 3

Learning Objective: 6.10 Describe the proper placement of the head and tail of a curved arrow

86) Which of the following correctly uses curved arrows to derive the corresponding resonance structure?

An illustration shows reactions, 1, 2, 3, 4, and 5 (in Roman numerals), in which a compound that has a SMILES string of CCNC(=O)C is converted into an intermediate ion. In reaction 1, a curved arrow points from the bond between the nitrogen atom and the carbonyl carbon atom toward the same nitrogen atom. Another curved arrow points from the oxygen atom toward the double bond between the oxygen atom and the carbonyl carbon atom. An intermediate ion is formed that has a similar structure as the compound except the nitrogen atom carries a positive charge, and oxygen atom carries a negative charge, and the nitrogen atom is double bonded to a carbon atom which is single bonded to the oxygen atom having a negative charge. In reaction 2, a curved arrow points from the nitrogen atom toward the bond between the nitrogen atom and the carbonyl carbon atom. Another curved arrow points from the double bond between the oxygen atom and the carbonyl carbon atom toward the same oxygen atom. An intermediate ion is formed that has a similar structure as the compound except the nitrogen atom carries a positive charge, and oxygen atom carries a negative charge, and the nitrogen atom is double bonded to a carbon atom which is single bonded to the oxygen atom having a negative charge. In reaction 3, a curved arrow points from the bond between the nitrogen atom and the carbonyl carbon atom toward the same nitrogen atom. Another curved arrow points from the double bond between the oxygen atom and the carbonyl carbon atom toward the oxygen atom. An intermediate ion is formed that has a similar structure as the compound except the nitrogen atom carries a positive charge, and oxygen atom carries a negative charge, and the nitrogen atom is double bonded to a carbon atom which is single bonded to the oxygen atom having a negative charge. In reaction 4, a curved arrow points from the nitrogen atom toward the bond between the nitrogen atom and the carbonyl carbon atom. Another curved arrow points from the double bond between the oxygen atom and the carbonyl carbon atom toward the same oxygen atom. An intermediate ion is formed that has a similar structure as the compound except the nitrogen atom is double bonded to a carbon atom which is single bonded to the oxygen atom. In reaction 5, a curved arrow points from the nitrogen atom toward the bond between the nitrogen atom and the carbonyl carbon atom. An intermediate ion is formed that has a similar structure as the compound except the nitrogen atom carries a positive charge, and oxygen atom carries a negative charge, and the nitrogen atom is double bonded to a carbon atom which is single bonded to the oxygen atom having a negative charge.

A) I

B) II

C) III

D) IV

E) V

Diff: 3

Learning Objective: 6.10 Describe the proper placement of the head and tail of a curved arrow

87) Which letters indicate the nucleophilic and electrophilic sites in the reactants of the reaction shown?

In a reaction, the reactant that has a SMILES string of CC(C)C=O reacts with L i single bonded to M e to form a product. The methyl group at C 2, oxygen atom, C 1, L i, and M e are labeled a through e. The product has a 3-carbon chain. C 1 is bonded to an oxygen anion and a methyl group, depicted as M e. C 2 is bonded to a methyl group. A lithium cation is present near the oxygen anion.

A) The nucleophile is c and the electrophile is e.

B) The nucleophile is b and the electrophile is d.

C) The nucleophile is e and the electrophile is c.

D) The nucleophile is a and the electrophile is c.

E) The nucleophile is b and the electrophile is e.

Diff: 1

Learning Objective: 6.10 Describe the proper placement of the head and tail of a curved arrow

88) Identify the nucleophilic and electrophilic sites in the substrate and reagent of the following reaction.

In a reaction, a reactant that has a SMILES string of c1ccc(cc1)C(=O)Cl reacts with methanol, M e O H to form a compound that has a SMILES string of COC(=O)c1ccccc1. An arrow, labeled, a points to C 1. An arrow, labeled, b points to the carbonyl carbon atom. An arrow, labeled, c points to the chlorine atom. An arrow, labeled, d points to the oxygen atom of methanol, M e O H.

A) The nucleophile is c and the electrophile is e.

B) The nucleophile is b and the electrophile is d.

C) The nucleophile is c and the electrophile is b.

D) The nucleophile is b and the electrophile is c.

E) The nucleophile is d and the electrophile is b.

Diff: 2

Learning Objective: 6.10 Describe the proper placement of the head and tail of a curved arrow

89) Will the carbocation shown undergo rearrangement?

The bond-line structure of a compound has a four-carbon chain, in which C 2 is bonded to a methyl group, and C 3 carries a positive charge.

A) Yes

B) No

Diff: 1

Learning Objective: 6.11 Discuss when a carbocation rearrangement will occur

90) Will the carbocation shown undergo rearrangement?

The bond-line structure of a compound has a four-carbon chain, in which C 2 is bonded to a methyl group, and carries a positive charge.

A) Yes

B) No

Diff: 1

Learning Objective: 6.11 Discuss when a carbocation rearrangement will occur

91) Will the carbocation shown undergo rearrangement?

The bond-line structure of a compound has a five-carbon chain, in which C 1 is bonded to a C 2, and C 4 carries a positive charge.

A) Yes

B) No

Diff: 1

Learning Objective: 6.11 Discuss when a carbocation rearrangement will occur

92) Will the carbocation shown undergo rearrangement?

The bond-line structure of a compound has a cyclohexane ring, in which C 1 is bonded to two methyl groups, and C 2 carries a positive charge.

A) Yes

B) No

Diff: 1

Learning Objective: 6.11 Discuss when a carbocation rearrangement will occur

93) Which of the structures shown is the most likely structure of the given carbocation after rearrangement?

The bond-line structure of a compound has a cyclopentane ring, in which C 1 is bonded to two methyl groups, and C 2 carries a positive charge.

An illustration shows bond-line structures of five cations, 1, 2, 3, 4, and 5 (in Roman numerals). Cation 1 has a cyclopentane ring, in which each C 1 and C 2 are bonded to a methyl group, C H 3, and C 1 carries a positive charge. Cation 2 has a cyclopentane ring, in which C 1 is bonded to a methyl group, C H 3, and carries a positive charge. Cation 3 has a cyclopentane ring, in which C 1 is bonded to a methyl group, C H 3, and C 2 carries a positive charge. Cation 4 has a cyclohexane ring, in which C 1 is bonded to a methyl group, C H 3, and carries a positive charge. Cation 5 has a cyclohexane ring, in which C 1 is bonded to a methyl group, C H 3, and C 2 carries a positive charge.

A) I

B) II

C) III

D) IV

E) V

Diff: 1

Learning Objective: 6.11 Discuss when a carbocation rearrangement will occur

94) What is the most likely structure of the carbocation shown after it has undergone rearrangement?

The bond-line structure of the compound has a five-carbon chain, in which C 1 is double bonded to C 2, and C 4 carries a positive charge.

An illustration shows bond-line structures of five cations, 1, 2, 3, 4, and 5 (in Roman numerals). Cation 1 has a five-carbon chain, in which C 1 is double bonded to C 2, and C 4 carries a positive charge. Cation 2 has a five-carbon chain, in which C 3 carries a positive charge. Cation 3 has a five-carbon chain, in which C 2 is double bonded to C 3, and C 1 carries a positive charge. Cation 4 has a five-carbon chain, in which C 1 carries a positive charge. Cation 5 has a five-carbon chain, in which C 1 is double bonded to C 2, and C 3 carries a positive charge.

A) I

B) II

C) III

D) IV

E) V

Diff: 3

Learning Objective: 6.11 Discuss when a carbocation rearrangement will occur

95) What is the most likely product for the following carbocation rearrangement?

The bond-line structure of the compound has a cyclohexane ring, in which C 1 is bonded to two methyl groups, and C 2 carries a positive charge.

An illustration shows bond-line structures of five cations, 1, 2, 3, 4, and 5 (in Roman numerals). Cation 1 has a cyclohexane ring, in which C 1 is bonded to a methyl group, and C 2 carries a positive charge. Cation 2 has a cyclohexane ring, in which C 1 is bonded to two methyl groups, and C 2 carries a positive charge. Cation 3 has a cyclohexane ring, in which each C 1 and C 2 are bonded to a methyl group, and C 1 carries a positive charge. Cation 4 has a cyclohexane ring, in which each C 1 and C 4 are bonded to a methyl group, and C 2 carries a positive charge. Cation 5 has a cyclohexane ring, in which C 1 carries a positive charge.

A) I

B) II

C) III

D) IV

E) V

Diff: 3

Learning Objective: 6.11 Discuss when a carbocation rearrangement will occur

96) Identify the appropriate reaction arrow for the following reaction.

An illustration shows an incomplete reaction, in which a cation reacts with a molecule of water, H 2 O, and another intermediate cation is formed. The cation has a four-carbon chain, in which C 2 is bonded to a methyl group, and carries a positive charge. The molecule of water has a central oxygen atom bonded to two hydrogen atoms on each side. The intermediate cation has a similar structure as the cation except C 2 is bonded to an oxygen atom which is further bonded to two hydrogen atoms, and the positive charge shifts on the oxygen atom. The reactants and the intermediate cation have a question mark in-between.

A) An illustration shows an arrow (highlighted) that points toward right.

B) An illustration shows an arrow (highlighted) that points toward left.

C) An illustration shows a reversible arrow(highlighted).

D) An illustration shows an arrow(highlighted) that points toward right, and has an X-mark on the tail.

Diff: 2

Learning Objective: 6.12 Describe reversible and irreversible reactions and how they are represented using arrows

97) Identify the appropriate reaction arrow for the following reaction.

An illustration shows an incomplete reaction, in which a compound forms a cation and an anion. The bond-line structure of the compound has a SMILES string of CC(C)Br. A curved arrow points from the bond between C 2 and the bromine atom toward the same bromine atom. A cation that has a three-carbon chain, in which C 2 carries and a positive charge, and a bromine anion, B r superscript minus are formed. The compound and the ions have a question mark in-between.

A) An illustration shows an arrow (highlighted) that points toward right.

B) An illustration shows an arrow (highlighted) that points toward left.

C) An illustration shows a reversible arrow(highlighted).

D) An illustration shows an arrow(highlighted) that points toward right, and has an X-mark on the tail.

Diff: 2

Learning Objective: 6.12 Describe reversible and irreversible reactions and how they are represented using arrows

98) Identify the appropriate reaction arrow for the following reaction.

An illustration shows an incomplete reaction, in which an anion forms another intermediate anion and carbon dioxide, C O 2. The bond-line structure of the anion has a four-carbon chain, in which C 1 is bonded to an oxygen atom that carries a lone pair of electrons and a negative charge, each C 1 and C 3 are double bonded to an oxygen atom. A curved arrow points from the negative charge on the oxygen atom toward the bond between the same oxygen atom and C 1. Another curved arrow points from the bond between C 1 and C 2 toward the adjacent bond between C 2 and C 3. The third curved arrow points from the double bond between C 3 and the oxygen atom toward the same oxygen atom. The intermediate anion has a three-carbon chain, in which C 1 is double bonded to C 2, and C 2 is bonded to an oxygen atom that carries a negative charge. Carbon dioxide has a central carbon atom which is double bonded to an oxygen atom on each side. The first anion and the second intermediate anion have a question mark in-between.

A) An illustration shows an arrow (highlighted) that points toward right.

B) An illustration shows an arrow (highlighted) that points toward left.

C) An illustration shows a reversible arrow(highlighted).

D) An illustration shows an arrow(highlighted) that points toward right, and has an X-mark on the tail.

Diff: 2

Learning Objective: 6.12 Describe reversible and irreversible reactions and how they are represented using arrows

© (2021) John Wiley & Sons, Inc. All rights reserved. Instructors who are authorized users of this course are permitted to download these materials and use them in connection with the course. Except as permitted herein or by law, no part of these materials should be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise.

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Document Type:
DOCX
Chapter Number:
6
Created Date:
Aug 21, 2025
Chapter Name:
Chapter 6 Chemical Reactivity And Mechanisms
Author:
David R. Klein

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