Question 1

The symbol Δ stands for ________ in a chemical reaction.

Accepted Answer

A) light 
B) heat 
C) reactant 
D) product 
A) light 
B) heat 
C) reactant 
D) product

Question 2

The DG° (free energy change)for the conversion of A to B is predicted to be which of the following?

Accepted Answer

A) DG° = 0 
B) DG°  0 
D) Cannot be determined from the information provided 
A) DG° = 0 
B) DG°  0 
D) Cannot be determined from the information provided

Question 3

Which step would most likely have the largest energy of activation?

Accepted Answer

A) Step one 
B) Step two 
C) Step three 
D) It cannot be determined from the information provided 
A) Step one 
B) Step two 
C) Step three 
D) It cannot be determined from the information provided

Question 4

Which of the following statements about the equilibrium constant,Keq,is true?

Accepted Answer

A) When Keq > 1,the equilibrium favors the reactants. 
B) When Keq eq tells about the position of equilibrium. 
D) For a reaction to be useful,the equilibrium must favor the reactants. 
A) When Keq > 1,the equilibrium favors the reactants. 
B) When Keq eq tells about the position of equilibrium. 
D) For a reaction to be useful,the equilibrium must favor the reactants.

Question 5

What type of bond cleavage takes place in/what type of intermediate is produced in the following reaction?

Accepted Answer

A) Homolysis/Radical 
B) Homolysis/Carbocation 
C) Heterolysis/Carbocation 
D) Heterolysis/Carbanion 
A) Homolysis/Radical 
B) Homolysis/Carbocation 
C) Heterolysis/Carbocation 
D) Heterolysis/Carbanion

Question 6

Which of the following statements is true?

Accepted Answer

A) The product is favored in reaction in which DH° is a positive value. 
B) Entropy decreases when an acyclic compound forms a ring. 
C) In homolytic bond cleavage,entropy decreases and favors formation of products. 
D) The starting material is favored in a reaction in which DH° is a negative value. 
A) The product is favored in reaction in which DH° is a positive value. 
B) Entropy decreases when an acyclic compound forms a ring. 
C) In homolytic bond cleavage,entropy decreases and favors formation of products. 
D) The starting material is favored in a reaction in which DH° is a negative value.

Question 7

Which of the following statements is true?

Accepted Answer

A) Bond dissociation energies increase down a column of the periodic table. 
B) When DH° is positive,more energy is released in forming bonds than is needed to break bonds. 
C) When DH° is negative,more energy is needed to break bonds than is released in forming bonds. 
D) Bond dissociation energies decrease down a column of the periodic table. 
A) Bond dissociation energies increase down a column of the periodic table. 
B) When DH° is positive,more energy is released in forming bonds than is needed to break bonds. 
C) When DH° is negative,more energy is needed to break bonds than is released in forming bonds. 
D) Bond dissociation energies decrease down a column of the periodic table.

Question 8

What kind of reaction does the conversion of A to B represent?

Accepted Answer

A) Addition reaction 
B) Substitution reaction 
C) Elimination reaction 
D) Acid-base reaction 
A) Addition reaction 
B) Substitution reaction 
C) Elimination reaction 
D) Acid-base reaction

Question 9

Which of the Keq corresponds to the highest value of DG°?

Accepted Answer

A) Keq = 10-1 
B) Keq = 10-2 
C) Keq = 10-3 
D) Keq = 10-5 
A) Keq = 10-1 
B) Keq = 10-2 
C) Keq = 10-3 
D) Keq = 10-5

Question 10

Which of the following statements is true?

Accepted Answer

A) Ionic intermediates are formed in radical reactions. 
B) Radicals are intermediates in polar reactions. 
C) Carbocations are electrophiles. 
D) Radicals are nucleophiles. 
A) Ionic intermediates are formed in radical reactions. 
B) Radicals are intermediates in polar reactions. 
C) Carbocations are electrophiles. 
D) Radicals are nucleophiles.

Question 11

Which reaction has a positive DG°,assuming that entropy changes are negligible compared to enthalpy changes?

Accepted Answer

A) A 
B) B 
C) C 
A) A 
B) B 
C) C

Question 12

How many transition states and intermediates would the reaction profile have for the reaction shown below?

Accepted Answer

A) Three transition states and three intermediates 
B) Two transition states and two intermediates 
C) Three transition states and two intermediates 
D) Two transition states and three intermediates 
A) Three transition states and three intermediates 
B) Two transition states and two intermediates 
C) Three transition states and two intermediates 
D) Two transition states and three intermediates

Question 13

For which of the following reactions is ΔS° a positive value?

Accepted Answer

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

Exam 6: Understanding Organic Reactions

The symbol Δ stands for ________ in a chemical reaction.

The DG° (free energy change)for the conversion of A to B is predicted to be which of the following?

Which step would most likely have the largest energy of activation?

Which of the following statements about the equilibrium constant,Keq,is true?

What type of bond cleavage takes place in/what type of intermediate is produced in the following reaction?

Which of the following statements is true?

Which of the following statements is true?

What kind of reaction does the conversion of A to B represent?

Which of the Keq corresponds to the highest value of DG°?

Which of the following statements is true?

Which reaction has a positive DG°,assuming that entropy changes are negligible compared to enthalpy changes?

How many transition states and intermediates would the reaction profile have for the reaction shown below?

For which of the following reactions is ΔS° a positive value?

Structure and Bonding

Acids and Bases

Introduction to Organic Molecules and Functional Groups

Alkanes

Stereochemistry

Alkyl Halides and Nucleophilic Substitution

Alkyl Halides and Elimination Reactions

Alcohols,ethers,and Related Compounds

Alkenes and Addition Reactions

Alkynes and Synthesis

Oxidation and Reduction

Radical Reactions

Conjugation, resonance, and Dienes

Benzene and Aromatic Compounds

Reactions of Aromatic Compounds

Introduction to Carbonyl Chemistry; Organometallic Reagents; Oxidation and Reduction

Aldehydes and Ketones - Nucleophilic Addition

Carboxylic Acids and the Acidity of the O-H Bond

Carboxylic Acids and Their Derivatives - Nucleophilic Acyl Substitution

Substitution Reactions of Carbonyl Compounds at the a Carbon

Carbonyl Condensation Reactions

Amines

Carbon-Carbon Bond-Forming Reactions in Organic Synthesis

Pericyclic Reactions

Carbohydrates

Amino Acids and Proteins

Synthetic Polymers

Lipids

Molecular Ion Peaks and Fragmentation Patterns

Analyzing Molecular Motion and Infrared Spectroscopy

Organic Spectroscopy Concepts

Filters

Which of the following statements about the equilibrium constant,K_eq,is true?

Which of the K_eq corresponds to the highest value of DG°?