Question 1

How many stereogenic centers are present in the following compound?

Accepted Answer

A) 1 
B) 2 
C) 3 
D) 4 
A) 1 
B) 2 
C) 3 
D) 4

Question 2

Which of the following is the definition for a pair of diastereomers?

Accepted Answer

A) A pair of stereoisomers with stereogenic centers but is not chiral. 
B) A pair of stereoisomers that are superimposable mirror images of each other. 
C) A pair of stereoisomers that are not superimposable mirror images of each other. 
D) A pair of stereoisomers that are not mirror images of each other. 
A) A pair of stereoisomers with stereogenic centers but is not chiral. 
B) A pair of stereoisomers that are superimposable mirror images of each other. 
C) A pair of stereoisomers that are not superimposable mirror images of each other. 
D) A pair of stereoisomers that are not mirror images of each other.

Question 3

A natural product was isolated in the laboratory, and its observed rotation was +10° when measured in a 1 dm sample tube containing 1.0 g of compound in 10 mL of H2O.What is the specific rotation of this compound?

Accepted Answer

A) -10° 
B) +100° 
C) +10° 
D) -100° 
A) -10° 
B) +100° 
C) +10° 
D) -100°

Question 4

Rank the following groups in order of decreasing priority according to the Cahn-Ingold-Prelog system.

Accepted Answer

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

Question 5

Rank the following groups in order of decreasing priority according to the Cahn-Ingold-Prelog system.

Accepted Answer

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

Question 6

Which of the following compounds can have a meso stereoisomer?

Accepted Answer

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

Question 7

How much of the R enantiomer is present in 10 g of a mixture that has an enantiomeric excess of 30% of the S isomer?

Accepted Answer

A) 3.0 g 
B) 3.5 g 
C) 6.5 g 
D) 7.0 g 
A) 3.0 g 
B) 3.5 g 
C) 6.5 g 
D) 7.0 g

Question 8

What is the relationship between the following compounds?

Accepted Answer

A) Constitutional isomers 
B) Diastereomers 
C) Enantiomers 
D) Identical 
A) Constitutional isomers 
B) Diastereomers 
C) Enantiomers 
D) Identical

Question 9

How many stereogenic centers are present in fructose, a simple sugar?

Accepted Answer

A) 1 
B) 2 
C) 3 
D) 4 
A) 1 
B) 2 
C) 3 
D) 4

Question 10

How many stereoisomers of 1,3-dibromocyclopentane exist?

Accepted Answer

A) 1 
B) 2 
C) 3 
D) 4 
A) 1 
B) 2 
C) 3 
D) 4

Question 11

Which of the following structures has the R configuration?

Accepted Answer

A) Only I 
B) Only II 
C) Only I and II 
D) I, II, and III 
A) Only I 
B) Only II 
C) Only I and II 
D) I, II, and III

Question 12

What is the main carbohydrate in the seeds and roots of plants?

Accepted Answer

A) Starch 
B) Glucose 
C) Cellulose 
D) Glycogen 
A) Starch 
B) Glucose 
C) Cellulose 
D) Glycogen

Question 13

How many stereogenic centers are present in menthol?

Accepted Answer

A) 1 
B) 2 
C) 3 
D) 4 
A) 1 
B) 2 
C) 3 
D) 4

Question 14

What is the relationship between the following compounds?

Accepted Answer

A) Constitutional isomers 
B) Diastereomers 
C) Enantiomers 
D) Identical 
A) Constitutional isomers 
B) Diastereomers 
C) Enantiomers 
D) Identical

Question 15

Which of the following structures has a different configuration from the other three?

Accepted Answer

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

Question 16

Which of the following statements about meso compounds is not true?

Accepted Answer

A) A meso compound generally has a plane of symmetry. 
B) A meso compound and its mirror image are identical. 
C) A meso compound is achiral. 
D) A meso compound is chiral. 
A) A meso compound generally has a plane of symmetry. 
B) A meso compound and its mirror image are identical. 
C) A meso compound is achiral. 
D) A meso compound is chiral.

Question 17

Which of the following statements is not true?

Accepted Answer

A) A molecule that is superimposable on its mirror image is said to achiral. 
B) A molecule that is not superimposable on its mirror image is said to be chiral. 
C) A molecule that is superimposable on its mirror image is said to be chiral. 
D) A carbon atom bonded to four different groups is a stereogenic center. 
A) A molecule that is superimposable on its mirror image is said to achiral. 
B) A molecule that is not superimposable on its mirror image is said to be chiral. 
C) A molecule that is superimposable on its mirror image is said to be chiral. 
D) A carbon atom bonded to four different groups is a stereogenic center.

Question 18

How many stereoisomers can be drawn for a molecule with formula CH3CH(OH)CH(OH)CH3?

Accepted Answer

A) 1 
B) 2 
C) 3 
D) 4 
A) 1 
B) 2 
C) 3 
D) 4

Question 19

Which of the following statements is true?

Accepted Answer

A) The presence of a plane of symmetry makes a molecule chiral. 
B) An achiral molecule must have one or more stereogenic centers. 
C) All molecules that have stereogenic centers are chiral. 
D) Stereoisomers that are not superimposable on their mirror image are enantiomers. 
A) The presence of a plane of symmetry makes a molecule chiral. 
B) An achiral molecule must have one or more stereogenic centers. 
C) All molecules that have stereogenic centers are chiral. 
D) Stereoisomers that are not superimposable on their mirror image are enantiomers.

Exam 5: Stereochemistry

How many stereogenic centers are present in the following compound?

Which of the following is the definition for a pair of diastereomers?

A natural product was isolated in the laboratory, and its observed rotation was +10° when measured in a 1 dm sample tube containing 1.0 g of compound in 10 mL of H2O.What is the specific rotation of this compound?

Rank the following groups in order of decreasing priority according to the Cahn-Ingold-Prelog system.

Rank the following groups in order of decreasing priority according to the Cahn-Ingold-Prelog system.

Which of the following compounds can have a meso stereoisomer?

How much of the R enantiomer is present in 10 g of a mixture that has an enantiomeric excess of 30% of the S isomer?

What is the relationship between the following compounds?

How many stereogenic centers are present in fructose, a simple sugar?

How many stereoisomers of 1,3-dibromocyclopentane exist?

Which of the following structures has the R configuration?

What is the main carbohydrate in the seeds and roots of plants?

How many stereogenic centers are present in menthol?

What is the relationship between the following compounds?

Which of the following structures has a different configuration from the other three?

Which of the following statements about meso compounds is not true?

Which of the following statements is not true?

How many stereoisomers can be drawn for a molecule with formula CH3CH(OH)CH(OH)CH3?

Which of the following statements is true?

Structure and Bonding

Acids and Bases

Introduction to Organic Molecules and Functional Groups

Alkanes

Understanding Organic Reactions

Alkyl Halides and Nucleophilic Substitution

Alkyl Halides and Elimination Reactions

Alcohols, Ethers, and Related Compounds

Alkenes

Alkynes

Oxidation and Reduction

Mass Spectrometry and Infrared Spectroscopy

Nuclear Magnetic Resonance Spectroscopy

Radical Reactions

Conjugation, Resonance, and Dienes

Benzene and Aromatic Compounds

Reactions of Aromatic Compounds

Carboxylic Acids and the Acidity of the O-H Bond

Introduction to Carbonyl Chemistry;

Aldehydes and Ketones Nucleophilic Addition

Carboxylic Acids and Derivatives

Substitution Reactions of Carbonyl Compounds at the Alpha-Carbon

Carbonyl Condensation Reactions

Amines

Carbon-Carbon Bond Forming Reactions in Organic Synthesis

Pericyclic Reactions

Carbohydrates

Amino Acids and Proteins

Synthetic Polymers

Lipids

Filters

A natural product was isolated in the laboratory, and its observed rotation was +10° when measured in a 1 dm sample tube containing 1.0 g of compound in 10 mL of H₂O.What is the specific rotation of this compound?

How many stereoisomers can be drawn for a molecule with formula CH₃CH(OH)CH(OH)CH₃?