Question 1

Place asterisks at all the chirality centers in each molecule below.
-The following atoms are commonly encountered in organic molecules. For which is it not possible to isolate enantiomers due to rapid inversion?

Accepted Answer

A)  trivalent phosphorus 
B)  trivalent nitrogen 
C)  divalent sulfur 
D)  trivalent sulfur 
E)  both b and c

Question 2

Which of the following compounds is (are) achiral? A  B  C  ​

Accepted Answer

A)  only A 
B)  only A and B 
C)  only B and C 
D)  A, B, and C

Question 3

If (+)-sucrose has a specific rotation of +66.47, what is the specific rotation of (−)-sucrose?

Accepted Answer

A)  +66.47 
B)  −66.47 
C)  +33.43 
D)  −33.43 
E)  Must be determined with a polarimeter.

Question 4

Match each definition to a term from the list below.
-Is an atom in a molecule that is bonded to four different atoms or groups of atoms.

Accepted Answer

A) racemates 
B) chirality center 
C) chirality 
D) diastereomers 
E) enantiomers
F)meso compounds
G)optically active
H)prochirality center
I)optically inactive
J)achiral
K)chirality center or meso compounds
L)enantiomers or optically active
M)optically active or optically inactive

Question 5

Match each definition to a term from the list below.
-Are stereoisomers that are not mirror images.

Accepted Answer

A) racemates 
B) chirality center 
C) chirality 
D) diastereomers 
E) enantiomers
F)meso compounds
G)optically active
H)prochirality center
I)optically inactive
J)achiral
K)chirality center or meso compounds
L)enantiomers or optically active
M)optically active or optically inactive

Question 6

Which of the following have the S configuration? A  B  C  ​
​

Accepted Answer

A)  only A 
B)  only B 
C)  only A and B 
D)  A, B, and C

Question 7

Match each definition to a term from the list below.
-Are molecules which contain both chirality centers and a plane of symmetry.

Accepted Answer

A) racemates 
B) chirality center 
C) chirality 
D) diastereomers 
E) enantiomers
F)meso compounds
G)optically active
H)prochirality center
I)optically inactive
J)achiral
K)chirality center or meso compounds
L)enantiomers or optically active
M)optically active or optically inactive

Question 8

2.10 g of an unknown compound was dissolved in 15.00 mL of ethanol. The sample was placed in a 10.0 cm cell in a polarimeter and the angle of rotation was determined to be −18.48°. What is the specific rotation of this unknown and specify if the compound is levorotatory or dextrorotatory?

Accepted Answer

The answer of 2.10 g of an unknown compound was...

Question 9

Which of the following have the R configuration? A  B  C  ​

Accepted Answer

A)  only A 
B)  only B 
C)  only A and B 
D)  A, B, and C

Question 10

Match each definition to a term from the list below.
-Are designated either (±) or d,l.

Accepted Answer

A) racemates 
B) chirality center 
C) chirality 
D) diastereomers 
E) enantiomers
F)meso compounds
G)optically active
H)prochirality center
I)optically inactive
J)achiral
K)chirality center or meso compounds
L)enantiomers or optically active
M)optically active or optically inactive

Question 11

In the molecules below, assign R, S configurations to the chirality center indicated with an arrow.   norepinephrine
alanine
-Refer to instructions. The configuration of this carbon atom is _____.

Accepted Answer

The answer of In the molecules below, assign R, S...

Question 12

Which of the following structures contain a plane of symmetry? A  B  C  ​

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  All three contain a plane of symmetry

Question 13

Identify the indicated hydrogens in the following molecules as pro-R or pro-S.
-Identify:  succinate

Accepted Answer

The answer of Identify the indicated hydrogens in the following...

Question 14

Which of the following is the definition of a meso compound?

Accepted Answer

A)  A molecule with chirality centers which is chiral 
B)  A molecule with chirality centers which is not chiral 
C)  A diastereomer with no chirality centers 
D)  A chiral compound with more than one chirality center

Question 15

How many stereoisomers of 2,3-dimethylbutane exist?

Accepted Answer

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

Question 16

Which of the following is the definition of a pair of enantiomers?

Accepted Answer

A)  A pair of structures that are superimposable mirror images of one another 
B)  A pair of stereoisomers that are non-superimposable mirror images of one another 
C)  A pair of stereoisomers that are not mirror images of one another 
D)  A pair of stereoisomers that have equal specific rotations

Question 17

Place asterisks at all the chirality centers in each molecule below.
-The numbers on the carbon center of the following molecule represent atomic numbers.  The molecule is in

Accepted Answer

A)  the R configuration. 
B)  the S configuration. 
C)  The carbon is not a chiral center in this molecule. 
D)  The exact configuration cannot be determined without knowing additional atomic numbers.

Question 18

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

Accepted Answer

A)  A pair of structures that are superimposable mirror images of one another 
B)  A pair of stereoisomers that are non-superimposable mirror images of one another 
C)  A pair of stereoisomers that are not mirror images of one another 
D)  A pair of stereoisomers that have equal specific rotations

Question 19

Identify the indicated hydrogens in the following molecules as pro-R or pro-S.
-Identify:  phenylpyruvate

Accepted Answer

The answer of Identify the indicated hydrogens in the following...

Question 20

(−)-cholesterol

Accepted Answer

A)  does not have a chiral center. 
B)  is dextrorotatory. 
C)  rotates the plane of polarized light counterclockwise. 
D)  does not rotate polarized light.

Exam 5: Stereochemistry at Tetrahedral Centers

Place asterisks at all the chirality centers in each molecule below. -The following atoms are commonly encountered in organic molecules. For which is it not possible to isolate enantiomers due to rapid inversion?

Which of the following compounds is (are) achiral? A B C

If (+) -sucrose has a specific rotation of +66.47, what is the specific rotation of (−) -sucrose?

Match each definition to a term from the list below. -Is an atom in a molecule that is bonded to four different atoms or groups of atoms.

Match each definition to a term from the list below. -Are stereoisomers that are not mirror images.

Which of the following have the S configuration? A B C

Match each definition to a term from the list below. -Are molecules which contain both chirality centers and a plane of symmetry.

2.10 g of an unknown compound was dissolved in 15.00 mL of ethanol. The sample was placed in a 10.0 cm cell in a polarimeter and the angle of rotation was determined to be −18.48°. What is the specific rotation of this unknown and specify if the compound is levorotatory or dextrorotatory?

Which of the following have the R configuration? A B C

Match each definition to a term from the list below. -Are designated either (±) or d,l.

In the molecules below, assign R, S configurations to the chirality center indicated with an arrow. norepinephrine alanine -Refer to instructions. The configuration of this carbon atom is _____.

Which of the following structures contain a plane of symmetry? A B C

Identify the indicated hydrogens in the following molecules as pro-R or pro-S. -Identify: succinate

Which of the following is the definition of a meso compound?

How many stereoisomers of 2,3-dimethylbutane exist?

Which of the following is the definition of a pair of enantiomers?

Place asterisks at all the chirality centers in each molecule below. -The numbers on the carbon center of the following molecule represent atomic numbers. The molecule is in

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

Identify the indicated hydrogens in the following molecules as pro-R or pro-S. -Identify: phenylpyruvate

(−) -cholesterol

Exam 5: Stereochemistry at Tetrahedral Centers

Place asterisks at all the chirality centers in each molecule below. -The following atoms are commonly encountered in organic molecules. For which is it not possible to isolate enantiomers due to rapid inversion?

Which of the following compounds is (are) achiral? A B C ​

If (+) -sucrose has a specific rotation of +66.47, what is the specific rotation of (−) -sucrose?

Match each definition to a term from the list below. -Is an atom in a molecule that is bonded to four different atoms or groups of atoms.

Match each definition to a term from the list below. -Are stereoisomers that are not mirror images.

Which of the following have the S configuration? A B C ​ ​

Match each definition to a term from the list below. -Are molecules which contain both chirality centers and a plane of symmetry.

2.10 g of an unknown compound was dissolved in 15.00 mL of ethanol. The sample was placed in a 10.0 cm cell in a polarimeter and the angle of rotation was determined to be −18.48°. What is the specific rotation of this unknown and specify if the compound is levorotatory or dextrorotatory?

Which of the following have the R configuration? A B C ​

Match each definition to a term from the list below. -Are designated either (±) or d,l.

In the molecules below, assign R, S configurations to the chirality center indicated with an arrow. norepinephrine alanine -Refer to instructions. The configuration of this carbon atom is _____.

Which of the following structures contain a plane of symmetry? A B C ​

Identify the indicated hydrogens in the following molecules as pro-R or pro-S. -Identify: succinate

Which of the following is the definition of a meso compound?

How many stereoisomers of 2,3-dimethylbutane exist?

Which of the following is the definition of a pair of enantiomers?

Place asterisks at all the chirality centers in each molecule below. -The numbers on the carbon center of the following molecule represent atomic numbers. The molecule is in

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

Identify the indicated hydrogens in the following molecules as pro-R or pro-S. -Identify: phenylpyruvate

(−) -cholesterol

Which of the following compounds is (are) achiral? A B C

Which of the following have the S configuration? A B C

Which of the following have the R configuration? A B C

Which of the following structures contain a plane of symmetry? A B C