Question 1

If a stereoisomer has an enantiomer,it does not have a diastereomer.

Accepted Answer

A) True 
 B)False

Question 2

Alanine,shown below,is a naturally occurring chiral amino acid. Which pair represents the two enantiomers of alanine?

Accepted Answer

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

Question 3

Any molecule with one chirality center is a chiral compound.

Accepted Answer

A) True 
 B)False

Question 4

Two enantiomers rotate plane-polarized light ________.

Accepted Answer

A) to an equal extent but in opposite directions 
B) to an equal extent in the same direction 
C) to vastly differing extents in random directions 
D) exactly 90º clockwise 
A) to an equal extent but in opposite directions 
B) to an equal extent in the same direction 
C) to vastly differing extents in random directions 
D) exactly 90º clockwise

Question 5

The amino acid alanine found in the proteins of the body has a melting point of 297 °C and a specific rotation of +8.5. The enantiomer of alanine would have a melting point of -297 °C and a specific rotation of -8.5.

Accepted Answer

A) True 
 B)False

Question 6

How can the following molecules be classified correctly?

Accepted Answer

A) II and III are identical molecules 
B) I and II are constitutional isomers 
C) I and III are stereoisomers 
D) II and III are stereoisomers 
E) Both statements B and D are correct 
A) II and III are identical molecules 
B) I and II are constitutional isomers 
C) I and III are stereoisomers 
D) II and III are stereoisomers 
E) Both statements B and D are correct

Question 7

Consider the stereoisomers (A-E)drawn below:   Which structure(s)is/are diastereomers of structure E?

Accepted Answer

A) Structure A 
B) Structure B 
C) Structure C 
D) Structure D 
E) Structures A and B 
A) Structure A 
B) Structure B 
C) Structure C 
D) Structure D 
E) Structures A and B

Question 8

A compound that does not change the direction of plane-polarized light is called

Accepted Answer

A) Chiral 
B) Diastereomer 
C) Achiral 
D) Neutral 
E) Acidic 
A) Chiral 
B) Diastereomer 
C) Achiral 
D) Neutral 
E) Acidic

Question 9

A carbonyl carbon is a common example of a chirality center.

Accepted Answer

A) True 
 B)False

Question 10

The dipeptide molecule shown below contains two chirality centers.

Accepted Answer

A) True 
 B)False

Question 11

Which choice is the enantiomer of the molecule given below?

Accepted Answer

A)    
B)    
C)    
D) None of these molecules is an enantiomer of the original molecule. 
A)    
B)    
C)    
D) None of these molecules is an enantiomer of the original molecule.

Question 12

Which molecule is not an enantiomer of the molecule whose structure is shown below?

Accepted Answer

A)    
B)    
C)    
D) All the molecules are enantiomers of the original structure. 
A)    
B)    
C)    
D) All the molecules are enantiomers of the original structure.

Question 13

A nail is an example of a chiral object.

Accepted Answer

A) True 
 B)False

Question 14

If one enantiomer causes plane-polarized light to rotate counterclockwise,that enantiomer is labeled as the (-)-enantiomer.

Accepted Answer

A) True 
 B)False

Question 15

Which statement concerning stereochemistry is incorrect?

Accepted Answer

A) An object or molecule is chiral if it is nonsuperimposable on its mirror image. 
B) A chiral molecule is optically active and rotates plane polarized light either clockwise or counterclockwise. 
C) Enantiomers are superimposable mirror image isomers. 
D) Diastereomers are stereoisomers that are not related as mirror images. 
A) An object or molecule is chiral if it is nonsuperimposable on its mirror image. 
B) A chiral molecule is optically active and rotates plane polarized light either clockwise or counterclockwise. 
C) Enantiomers are superimposable mirror image isomers. 
D) Diastereomers are stereoisomers that are not related as mirror images.

Question 16

Which structure represents the three-dimensional structure of the Fischer projection shown?

Accepted Answer

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

Question 17

In organic molecules,oxygen atoms cannot be chirality centers.

Accepted Answer

A) True 
 B)False

Question 18

For an odor to be perceived,a molecule must bind to an olfactory receptor,resulting in a nerve impulse that travels to the brain.

Accepted Answer

A) True 
 B)False

Question 19

Two enantiomers typically have the same biological activity.

Accepted Answer

A) True 
 B)False

Question 20

The Fischer projection to the right represents the compound to the left.

Accepted Answer

A) True 
 B)False

Exam 15: The Three-Dimensional Shape of Molecules

If a stereoisomer has an enantiomer,it does not have a diastereomer.

Alanine,shown below,is a naturally occurring chiral amino acid. Which pair represents the two enantiomers of alanine?

Any molecule with one chirality center is a chiral compound.

Two enantiomers rotate plane-polarized light ________.

The amino acid alanine found in the proteins of the body has a melting point of 297 °C and a specific rotation of +8.5. The enantiomer of alanine would have a melting point of -297 °C and a specific rotation of -8.5.

How can the following molecules be classified correctly?

Consider the stereoisomers (A-E)drawn below: Which structure(s)is/are diastereomers of structure E?

A compound that does not change the direction of plane-polarized light is called

A carbonyl carbon is a common example of a chirality center.

The dipeptide molecule shown below contains two chirality centers.

Which choice is the enantiomer of the molecule given below?

Which molecule is not an enantiomer of the molecule whose structure is shown below?

A nail is an example of a chiral object.

If one enantiomer causes plane-polarized light to rotate counterclockwise,that enantiomer is labeled as the (-)-enantiomer.

Which statement concerning stereochemistry is incorrect?

Which structure represents the three-dimensional structure of the Fischer projection shown?

In organic molecules,oxygen atoms cannot be chirality centers.

For an odor to be perceived,a molecule must bind to an olfactory receptor,resulting in a nerve impulse that travels to the brain.

Two enantiomers typically have the same biological activity.

The Fischer projection to the right represents the compound to the left.

Matter and Measurement

Atoms and the Periodic Table

Ionic Compounds

Covalent Compounds

Chemical Reactions

Energy Changes,reaction Rates,and Equilibrium

Gases,liquids,and Solids

Solutions

Acids and Bases

Nuclear Chemistry

Introduction to Organic Molecules and Functional Groups

Alkanes

Unsaturated Hydrocarbons

Organic Compounds That Contain Oxygen,halogen,or Sulfur

Aldehydes and Ketones

Carboxylic Acids,esters,and Amides

Amines and Neurotransmitters

Lipids

Carbohydrates

Amino Acids,proteins,and Enzymes

Nucleic Acids and Protein Synthesis

Metabolism and Energy Production

Carbohydrate,lipid,and Protein Metabolism

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