Question 1

A mixture of equal amounts of two enantiomers ________.

Accepted Answer

A) is called a racemic mixture 
B) is optically inactive 
C) implies that the enantiomers are meso forms 
D) both A and B 
E) none of the above 
A) is called a racemic mixture 
B) is optically inactive 
C) implies that the enantiomers are meso forms 
D) both A and B 
E) none of the above

Question 2

What is the relationship between the structures shown below?

Accepted Answer

A) enantiomers 
B) diastereomers 
C) configurational isomers 
D) identical compounds 
E) constitutional isomers 
A) enantiomers 
B) diastereomers 
C) configurational isomers 
D) identical compounds 
E) constitutional isomers

Question 3

Which of the statements below correctly describes an achiral molecule?

Accepted Answer

A) The molecule has a nonsuperimposable mirror image. 
B) The molecule exhibits optical activity when it interacts with plane-polarized light. 
C) The molecule has an enantiomer. 
D) The molecule might be a meso form. 
E) none of the above 
A) The molecule has a nonsuperimposable mirror image. 
B) The molecule exhibits optical activity when it interacts with plane-polarized light. 
C) The molecule has an enantiomer. 
D) The molecule might be a meso form. 
E) none of the above

Question 4

Give the number of asymmetric centers in limonene.

Accepted Answer

A) 2 
B) 3 
C) 1 
D) 5 
E) 4 
A) 2 
B) 3 
C) 1 
D) 5 
E) 4

Question 5

Which of the following terms best describes the pair of compounds shown: enantiomers, diastereomers, or the same compound?

Accepted Answer

The answer of Which of the following terms best describes...

Question 6

Is the molecule shown chiral? Is it a meso compound?

Accepted Answer

not chiral

Question 7

Is the molecule shown below chiral or achiral?

Accepted Answer

The answer of Is the molecule shown below chiral or...

Question 8

Identify all configurational isomers.

Accepted Answer

A) B and D, A and C 
B) A and C 
C) B and D 
D) A and B, A and D, B and C, C and D 
E) B and D, A and B, A and D, B and C, C and D 
A) B and D, A and C 
B) A and C 
C) B and D 
D) A and B, A and D, B and C, C and D 
E) B and D, A and B, A and D, B and C, C and D

Question 9

A sample of (+)and (-)-3-chlorohexane has a rotation of -20 degrees. Pure (+)-3-chlorohexane has a rotation of +40 degrees. Calculate the enantiomeric excess and the amount of (-)and (+)-3-chlorohexane in the original sample.

Accepted Answer

50%, 75% (

Question 10

Give the complete name(s)of the following compound.

Accepted Answer

(2R, 4S)-2,4-dichlor

Question 11

Is the molecule shown chiral? Is it a meso compound?

Accepted Answer

not chiral

Question 12

What is the relationship between the following compounds?

Accepted Answer

A) superimposable without bond rotation 
B) constitutional isomers 
C) conformational isomers 
D) diastereomers 
E) enantiomers 
A) superimposable without bond rotation 
B) constitutional isomers 
C) conformational isomers 
D) diastereomers 
E) enantiomers

Question 13

Provide a careful structure for (2S,3R)-2,3-dibromohexane.

Accepted Answer

The answer of Provide a careful structure for (2S,3R)-2,3-dibromohexane....

Question 14

In the Fischer projection below, what are the configurations of the two asymmetric centers?

Accepted Answer

A) 2R, 3R 
B) 2R, 3S 
C) 2S, 3R 
D) 2S, 3S 
E) cannot be determined from structure 
A) 2R, 3R 
B) 2R, 3S 
C) 2S, 3R 
D) 2S, 3S 
E) cannot be determined from structure

Question 15

Twenty grams of a compound was dissolved in 100 mL of solvent and gave an observed rotation of -20 degrees. The sample tube is 4 dm long. Calculate the specific rotation.

Accepted Answer

The answer of Twenty grams of a compound was dissolved...

Question 16

Which of the following statements correctly describes the molecule shown below?

Accepted Answer

A) It is achiral. 
B) It is meso. 
C) Its asymmetric center possesses the R configuration. 
D) The mirror image of this molecule is its enantiomer. 
E) The molecule possesses enantiotopic hydrogens. 
A) It is achiral. 
B) It is meso. 
C) Its asymmetric center possesses the R configuration. 
D) The mirror image of this molecule is its enantiomer. 
E) The molecule possesses enantiotopic hydrogens.

Question 17

Is the molecule shown below chiral or achiral?

Accepted Answer

The answer of Is the molecule shown below chiral or...

Question 18

Draw the structure of (2S,3R)-dichloropentane. Take particular care to indicate three-dimensional stereochemistry detail properly.

Accepted Answer

The answer of Draw the structure of (2S,3R)-dichloropentane. Take particular...

Question 19

Which of the following compounds has an asymmetric center?

Accepted Answer

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

Question 20

Which of the following is a meso compound?

Accepted Answer

A) trans-1, 4-dimethylcyclohexane 
B) cis-1, 3-dimethylcyclohexane 
C) trans-1, 3-dimethylcyclohexane 
D) cis-1, 4-dimethylcyclohexane 
E) trans-1, 2-dimethylcyclohexane 
A) trans-1, 4-dimethylcyclohexane 
B) cis-1, 3-dimethylcyclohexane 
C) trans-1, 3-dimethylcyclohexane 
D) cis-1, 4-dimethylcyclohexane 
E) trans-1, 2-dimethylcyclohexane

Exam 4: Isomers: the Arrangement of Atoms in Space

A mixture of equal amounts of two enantiomers ________.

What is the relationship between the structures shown below?

Which of the statements below correctly describes an achiral molecule?

Give the number of asymmetric centers in limonene.

Which of the following terms best describes the pair of compounds shown: enantiomers, diastereomers, or the same compound?

Is the molecule shown chiral? Is it a meso compound?

Is the molecule shown below chiral or achiral?

Identify all configurational isomers.

A sample of (+)and (-)-3-chlorohexane has a rotation of -20 degrees. Pure (+)-3-chlorohexane has a rotation of +40 degrees. Calculate the enantiomeric excess and the amount of (-)and (+)-3-chlorohexane in the original sample.

Give the complete name(s)of the following compound.

Is the molecule shown chiral? Is it a meso compound?

What is the relationship between the following compounds?

Provide a careful structure for (2S,3R)-2,3-dibromohexane.

In the Fischer projection below, what are the configurations of the two asymmetric centers?

Twenty grams of a compound was dissolved in 100 mL of solvent and gave an observed rotation of -20 degrees. The sample tube is 4 dm long. Calculate the specific rotation.

Which of the following statements correctly describes the molecule shown below?

Is the molecule shown below chiral or achiral?

Draw the structure of (2S,3R)-dichloropentane. Take particular care to indicate three-dimensional stereochemistry detail properly.

Which of the following compounds has an asymmetric center?

Which of the following is a meso compound?

Remembering General Chemistry: Electronic Structure and Bonding

Acids and Bases: Central to Understanding Organic Chemistry

An Introduction to Organic Compounds

Alkenes Thermodynamics and Kinetics

Reactions of Alkenes

Reactions of Alkynes Introduction to Multistep Synthesis

Electron Delocalization, Resonance, and Aromaticity More About Molecular Orbital Theory

Substitution Reactions of Alkyl Halides

Elimination Reactions of Alkyl Halides Competition Between Substitution and Elimination

Reactions of Alcohols, Ethers, Epoxides, and Sulfur-Containing Compounds

Organometallic Compounds

Reactions of Alkanes, Radicals

Mass Spectrometry, Infrared Spectroscopy, and Uvvis Spectroscopy

Nmr Spectroscopy

Reactions of Carboxylic Acids and Carboxylic Acid Derivatives

Reactions of Aldehydes and Ketones

Reactions at the Alpha Carbon of Carbonyl Compounds

Reactions of Benzene and Substituted Benzenes

More About Amines Heterocylic Compounds

Carbohydrates

Amino Acids, Peptides, and Proteins

Catalysis

The Organic Mechanisms of the Coenzymes

The Chemistry of Metabolism

Nucleosides, Nucleotides, and Nucleic Acids

Synthetic Polymers

Pericyclic Reactions

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