Deck 20: Organic Chemistry I: Structures

Question 1

What is the maximum number of covalent bonds that a carbon atom can form?

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

Answer 1

4

Question 2

Which of the following acyclic compounds is an alkane?

A) C₁₀H₂₂
B) C₁₁H₂₂
C) C₁₂H₂₂
D) C₅H₁₀
E) C₅H₈

Answer 2

C₁₀H₂₂

Question 3

Identify the hybridization of carbon atoms numbered 1-6 in the structure below:

A) Carbons 1 and 2 are sp³, carbons 3 and 6 are sp², carbons 4 and 5 are sp hybridized.
B) Carbons 1 and 3 are sp³, carbons 2 and 5 are sp², carbons 4 and 6 are sp hybridized.
C) Carbons 2 and 3 are sp³, carbons 4 and 5 are sp², carbons 1 and 6 are sp hybridized.
D) Carbons 4 and 5 are sp³, carbons 3 and 6 are sp², carbons 1 and 2 are sp hybridized.
E) Carbons 3 and 6 are sp³, carbons 4 and 5 are sp², carbons 1 and 2 are sp hybridized.

Answer 3

Carbons 1 and 2 are sp³, carbons 3 and 6 are sp², carbons 4 and 5 are sp hybridized.

Question 4

Identify the generic formula for alkenes.

A) C_nH_2n+4
B) C_nH_2n+-2
C) C_nH_2n+1
D) C_nH_2n
E) C_nH_2n-4

Question 5

Which of the following compounds is a ketone?

A) CH₃CH₂CH₂CO₂H
B)
C) CH₃CH₂NH₂
D)
E)

Question 6

Which of the following acyclic compounds is an alkene with one double bond in its structure?

A) C₁₀H₂₂
B) C₁₁H₂₂
C) C₁₂H₂₂
D) C₆H₁₀
E) C₅H₈

Question 7

Which of the following compounds is an alcohol?

A) CH₃CH₂CH₂C(=O)OH
B) CH₃-O-CH₂CH₃
C) CH₃CO₂CH₃
D) CH₂OH-CH₂OH
E) CH₃CH₂CH=O

Question 8

Which of the following acyclic compounds is an alkyne with one triple bond in its structure?

A) C₁₀H₂₂
B) C₁₁H₂₂
C) C₁₂H₂₂
D) C₉H₁₈
E) C₅H₁₀

Question 9

Which of the following functional groups is found in amines?

A) -C≡N
B) -NO₂
C) -NH₂
D) -N≡N
E) -N=NH

Question 10

Which of the following statements regarding functional groups and families is TRUE?

A) A group of organic compounds forms a family if they share the same characteristic carbon atom backbone called the functional group.
B) A group of organic compounds forms a family if they share the same characteristic atom or a group of atoms called the functional group.
C) A group of organic compounds forms a family if they differ by one CH group, called the functional group, in their structure.
D) A family of organic compounds are all structural isomers with the same molecular formula called the functional group formula.
E) A family of organic compounds is composed of all isomers that have the same molecular formula and share the same characteristic atom or a group of atoms called the functional group.

Question 11

Which of the following compounds is a carboxylic acid?

A)
B)
C)
D)
E)

Question 12

Which of the following statements is TRUE?

A) Organic halides are polar molecules with C-X bond polarity increasing in order C-Br < C-I < C-Cl < C-F.
B) Alkenes are hydrocarbons that contain one or more C=C bonds and therefore must have some carbons sp hybridized.
C) Amines are organic compounds that contain nitrogen and have R-C(=O)-NH-R as their general formula.
D) Ethers are a family of organic compounds that contain oxygen and have the general formula R-O-R.
E) Because alcohols contain nonpolar C-H bonds, they cannot mix with water.

Question 13

Which one of the following structures belongs to the amide family?

A)
B)
C)
D)
E)

Question 14

Identify the generic formula for alkanes.

A) C_nH_2n+2
B) C_nH_2n-2
C) C_nH_2n
D) C_nH_2n-4
E) C_nH_2n+4

Question 15

Which of the following compounds is an aldehyde?

A) CH₃CH₂CH=O
B) CH₃CH₂CH₂CO₂H
C) CH₃CO₂CH₃
D) CH₃-O-CH₃
E) CH₂OH-CH₂OH

Question 16

Which of the following compounds is an ester?

A)
B)
C)
D)
E)

Question 17

Which of the following compounds is an amine?

A) (CH₃CH₂)₂NH
B) CH₃CH₂CH₂CH₂CO₂CH₃
C) CH₃CH₂CH₂CH₂-O-CH₂CH₂CH₃
D) CH₃CH=O
E) CH₃COCH₃

Question 18

Identify hybridization of carbon atoms numbered 1-6 in the structure below:

A) Carbons 3, 4, and 6 are sp³, carbons 1, 2 and 5 are sp hybridized.
B) Carbons 2, 3, and 4 are sp³, carbons 1, 5, and 6 are sp² hybridized.
C) Carbons 2, 3, 4, and 6 are sp³, carbons 1 and 5 are sp² hybridized.
D) Carbons 2, 3, 4, and 6 are sp³, carbons 1 and 5 are sp hybridized.
E) Carbons 3, 4, and 6 are sp³, carbons 1, 2, and 5 are sp² hybridized.

Question 19

When does conjugation occur?

A) Conjugation occurs every time an organic molecule has a heteroatom in its structure regardless of hybridization.
B) Conjugation occurs every time an organic molecule has a sequence of three or more sp² hybridized atoms.
C) Conjugation occurs every time an organic molecule has a sequence of three or more sp³ hybridized atoms.
D) Conjugation occurs every time an organic molecule has a sequence of two or more sp² hybridized atoms.
E) Conjugation occurs every time an organic molecule has a ring-type structure.

Question 20

Which of the following compounds is an ether?

A)
B)
C)
D)
E)

Question 21

Which of the following structures shows a primary amine?

A)
B)
C)
D)
E)

Question 22

Which of the following alcohols has the lowest solubility in water?

A) CH₃CH₂OH
B) CH₃CH₂CH₂CH₂OH
C) CH₃CH₂CH₂CH₂CH₂OH
D) CH₃CH₂CH₂CH₂CH₂CH₂OH
E) CH₃CH₂CH₂CH₂CH₂CH₂CH₂CH₂OH

Question 23

Which of the following organic families contains nearly nonpolar compounds?

A) carboxylic acids
B) alcohols
C) amines
D) esters
E) ethers

Question 24

Which of the following alcohols has the highest solubility in water?

A) CH₃CH₂OH
B) CH₃CH₂CH₂CH₂OH
C) CH₃CH₂CH₂CH₂CH₂OH
D) CH₃CH₂CH₂CH₂CH₂CH₂OH
E) CH₃CH₂CH₂CH₂CH₂CH₂CH₂CH₂OH

Question 25

Which one of the following molecules is the most polar?

A) butane
B) acetic acid
C) cyclohexane
D) methanol
E) cyclohexanone

Question 26

Which of the following condensed general formulas represents tertiary alcohols?

A) RCH₂OR
B) RCH₂OH
C) R₃COR
D) R₃COH
E) R₃CCH₂OH

Question 27

Which of the following compounds is ethanol?

A) C₂H₆
B) C₂H₅OH
C) CH₃CO₂H
D) CH₃CO₂CH₃
E) CH₃-O-CH₃

Question 28

Which of the following is a secondary alcohol?

A) CH₃CH₂OH
B) (CH₃)₂(CH₃CH₂)COH
C) (CH₃)₃COH
D) (CH₃)₂CHCH(CH₃)OH
E) CH₃OCH₃

Question 29

Which of the following molecules is the least polar?

A) octanol
B) cyclohexane
C) ethylamine
D) dodecanol
E) cyclohexanone

Question 30

Which of the following is a primary alcohol?

A) CH₃CH₂OH
B) (CH₃)₂CHOH
C) (CH₃)₃COH
D) (CH₃)₂CHCH(CH₃)OH
E) CH₃OCH₃

Question 31

Which of the following condensed general formulas represents alcohols?

A) ROR
B) RCOR
C) RCHO
D) ROH
E) RCOOH

Question 32

Which of the following statements correctly describes organic halides?

A) Organic halides have one or more H atoms substituted by an electronegative atom from group 16 of the periodic table.
B) Organic halides have one or more C atoms substituted by an electronegative atom from group 17 of the periodic table.
C) Organic halides have one or more H atoms substituted by an electronegative atom from group 17 of the periodic table.
D) Organic halides have one or more H atoms substituted by an electropositive atom from group 17 of the periodic table.
E) Organic halides have one or more H atoms substituted by an electronegative atom from group 7 of the periodic table.

Question 33

Which of the following compounds contain an acyl group?

A) esters, ethers, carboxylic acids
B) esters, carboxylic acids, amines
C) esters, carboxylic acids, amides
D) esters, alcohols, amines
E) ethers, amides, esters

Question 34

Which of the following condensed general formulas represents ethers?

A) RCOR
B) RCHO
C) ROR
D) ROH
E) RCONH₂

Question 35

Which of the following sets of compounds contain one ether, one alcohol, and one ketone (not necessarily in this order)?

A)
B)
C)
D)
E)

Question 36

Which of the following is a tertiary alcohol?

A) CH₃CH₂OH
B) (CH₃)₂CHOH
C) (CH₃)₃COH
D) (CH₃)₂CHCH(CH₃)OH
E) CH₃OCH₃

Question 37

Which of the following structures shows a secondary amine?

A)
B)
C)
D)
E)

Question 38

Which two functional groups combined give the functional group found in carboxylic acids?

A) carbonyl and hydroxyl
B) carbonyl and amine
C) ether and hydroxyl
D) ester and hydroxyl
E) chlorido and carbonyl

Question 39

Which of the following condensed general formulas represents aldehydes?

A) ROR
B) RCOR
C) RCHO
D) ROH
E) RCOOH

Question 40

Which compound is a saturated hydrocarbon?

A) 1-butyne
B) acetylene
C) 3-methylheptane
D) 2-methylheptene
E) ethene

Question 41

Which of the following lists the substituents in the order of priority, from highest (priority 1) to lowest (priority 4)?

A) -Cl, -CH₂CH₃, -CH=CH₂, -CH₃
B) -OH, -CH₂CH₃, -CH=CH₂, CH₃
C) -NH₂, -CONH₂, -COOH, CH₃
D) -NH₂, -COOH, -C(=O)H, -CH₃
E) -Cl, -Br, -OH, -H

Question 42

Which of the following pairs of organic compound families could have constitutional isomers?

A) an ether and an alcohol
B) an amide and an amine
C) an ether and a carboxylic acid
D) a carboxylic acid and an amide
E) an amine and an alcohol

Question 43

Which of the following statements is TRUE?

A) Enantiomers are molecules that are nonsuperimposable mirror images of each other and they have a chiral sp² carbon atom with four different substituents in a tetrahedral arrangement.
B) Enantiomers are molecules that are nonsuperimposable mirror images of each other and they have a prochiral carbon atom with four different substituents in a tetrahedral arrangement.
C) Enantiomers are molecules that are superimposable mirror images of each other and they have a chiral carbon atom with four different substituents in a tetrahedral arrangement.
D) Enantiomers are molecules that are nonsuperimposable mirror images of each other and they have a chiral carbon atom with four different substituents in a planar arrangement.
E) Enantiomers are molecules that are nonsuperimposable mirror images of each other and they have a chiral carbon atom with four different substituents in a tetrahedral arrangement.

Question 44

Which of the following pairs are constitutional isomers?

A) CH₃CH=CHCH₂OH and CH₃CH=CHOCH₃
B) ClCH₂CH₂CH₂CH₃ and CH₃CH₂CH₂CH₂Cl
C) CH₃CH(OH)CH₂CH₃ and CH₃CH₂(HO)CHCH₃
D) H₂NCH₂CH=CHCOOH and HOOCCH=CH(H₂N)CH₂
E) CH₃OCH₂CH₂CH₂CH₃ and CH₃OCH₂CH₂CH₂OCH₃

Question 45

Which of the following is TRUE regarding constitutional isomers?

A) Constitutional isomers have the same molecular formula but different structures, physical, and chemical properties.
B) Constitutional isomers have the same molecular formula and physical properties but different structures and chemical properties.
C) Constitutional isomers have the same molecular formula, physical, and chemical properties but different structures.
D) Constitutional isomers have the same chemical structure and molecular formula but different physical and chemical properties.
E) Constitutional isomers have the same chemical structure but different formulas, physical, and chemical properties.

Question 46

Which of the following structures shows an E alkene isomer?

A)
B)
C)
D)
E)

Question 47

Which of the following structures shows a Z alkene isomer?

A)
B)
C)
D)
E)

Question 48

Which of the following is a constitutional isomer of the following organic molecule?

A)
B)
C)
D)
E)

Question 49

Which of the following compounds exhibit optical isomerism?

A) sec-butylbenzene
B) CH₂Cl₂
C) CF₂BrI
D) CHBr₂I
E) tert-butylbenzene

Question 50

Find the correct Newman projection formula showing a staggered conformer of n-hexane.

A)
B)
C)
D)
E)

Question 51

What is angle strain in cycloalkanes?

A) Angle strain is the angle between carbon bonds on the outer side of a cycloalkane ring.
B) Angle strain is the difference between an ideal bond angle for sp³ hybridized carbon atoms and the actual bond angle in the ring.
C) Angle strain is the difference between and ideal bond angle for sp hybridized carbon atoms and the actual bond angle in the ring.
D) Angle strain is the angle between C-C bonds in the cycloalkane ring.
E) Angle strain is the difference between the C-C bond angles found in a flat ring structure and in an actual ring structure.

Question 52

Which of the following structures are constitutional isomers of a compound with molecular formula C₄H₉N?

A)
B)
C)
D)
E)

Question 53

Which of the following Newman projections shows a staggered conformer of 2-methyl-butane?

A)
B)
C)
D)
E)

Question 54

Which of the following compounds exhibit cis-trans isomerism?

A) CH₂=CH-CH₃
B) CCl₂=CBr₂
C) CH₃-CH=CH-CH₃
D) CCl₂=CHBr
E) (CH₃)₂C=CH(CH₃)

Question 55

Which of the following is TRUE regarding stereoisomers?

A) Stereoisomers differ in the way atoms are connected but have identical spatial orientation of atoms. They can be conformational or configurational.
B) Stereoisomers differ in the way atoms are connected but have identical spatial orientation of atoms. They can be constitutional or configurational.
C) Stereoisomers have the same atom connectivity but have different spatial orientation of atoms. They can be constitutional or enantiomeric.
D) Stereoisomers have the same atom connectivity but have different spatial orientation of atoms. They can be conformational or configurational.
E) Stereoisomers have the same atom connectivity but have different functional groups on the same positions of the carbon backbone. They can be conformational or configurational.

Question 56

Which of the following compounds exhibit cis-trans isomerism?

A) CH₂=CH₂
B) CH₂=CCl₂
C) CBr₂=CHBr
D) CHCl=CHCl
E) (CH₃)₂C=CH-CH₂CH₃

Question 57

Find the correct statement about cis-trans isomers.

A) Cis-trans isomers are diastereomers and occur because the rotation around a C≡C bond is very restricted.
B) Cis-trans isomers are enantiomers and occur because the rotation around a C=C bond is very restricted.
C) Cis-trans isomers are diastereomers and occur because the rotation around a C=C bond is very restricted.
D) Cis-trans isomers are superimposable constitutional isomers of substituted alkenes formed around a C=C bond.
E) Cis-trans isomers are chiral molecules and occur because the rotation around a C=C bond is very restricted.

Question 58

Which of the following Newman projections shows an antistaggered conformation of n-pentane?

A)
B)
C)
D)
E)

Question 59

Which of the following lists the substituents in the order of priority, from highest (priority 1) to lowest (priority 4)?

A) -CH₃, -CH=CH₂, -CH₂CH₃, -Cl
B) -CH₃, -CH₂CH₃, -CH=CH₂, -Cl
C) -Cl, -CH₂CH₃, -CH₃, -CH=CH₂
D) -Cl, -CH₂CH₃, -CH=CH₂, -CH₃
E) -Cl, -CH=CH₂, -CH₂CH₃, -CH₃

Question 60

Which of the following lists the substituents in the order of priority, from highest (priority 1) to lowest (priority 4)?

A) -NH₂, -C(=O)H, -COOH, -CH₃
B) -CH₃, -COOH, -C(=O)H, -NH₂
C) -NH₂, -CH₃, -C(=O)H, -COOH
D) -NH₂, -COOH, -C(=O)H, -CH₃
E) -NH₂, -CH₃, -COOH, -C(=O)H

Question 61

The general formula for alkanes is C_nH_2n+2. What is the value of n in 3,7-dimethyldecane? How many chiral centres does this molecule have?

A) n = 10; there are two chiral centres
B) n = 10; there is one chiral centre
C) n = 12; there are two chiral centres
D) n = 12; there are three chiral centres
E) n = 12; there is one chiral centre

Question 62

Determine the absolute configuration of the molecule shown below:

A) S configuration
B) R configuration
C) E configuration
D) Z configuration
E) l configuration

Question 63

How many of the carbons in the following compound are chiral centre(s)?

A) 0
B) 1
C) 2
D) 3
E) 4

Question 64

Determine the absolute configuration of the molecule shown below:

A) S configuration
B) R configuration
C) E configuration
D) Z configuration
E) l configuration

Question 65

Which of the following statements is TRUE?

A) Optical activity describes the property of a chiral compound to rotate the plane of polarized light.
B) Two enantiomers differ significantly in physical properties. This difference is the basis for the separation of the two enantiomers from a racemic mixture.
C) A racemic mixture is an optically active mixture of two enantiomers.
D) It is possible to determine if an enantiomer is the levorotatory or dextrorotatory isomer by analyzing its infrared spectrum.
E) If an enantiomer has an S absolute configuration then it must be the levorotatory isomer.

Question 66

What is the index of hydrogen deficiency in C₁₀H₁₂N₂O₃?

A) 5
B) 4
C) 3
D) 2
E) 6

Question 67

Which of the following structures is S-2-chlorobutane?

A)
B)
C)
D)
E)

Question 68

The general formula for alkanes is C_nH_2n+2. What is the value of n in 3-ethyl-4,7-dimethylnonane? How many chiral centres does this molecule have?

A) n = 9; there are two chiral centres
B) n = 9; there are three chiral centres
C) n = 13; there are two chiral centres
D) n = 13; there are three chiral centres
E) n = 13; there is one chiral centre

Question 69

In which of the following structures have the group priorities been assigned correctly?

A)
B)
C)
D)
E)

Question 70

How many of the carbons in the following compound are chiral centre(s)?

A) 0
B) 1
C) 2
D) 3
E) 4 or more

Question 71

Which of the following structures are enantiomers?

A)
B)
C)
D)
E)

Question 72

What is the index of hydrogen deficiency in C₂₀H₃₆?

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

Question 73

Determine the absolute configuration of the molecule shown below:

A) R configuration
B) S configuration
C) E configuration
D) Z configuration
E) d configuration

Question 74

Which of the following have correct assignments of both group priorities and absolute configurations?

A) , R configuration
B) , S configuration
C) , S configuration
D) , l configuration
E) , d configuration

Question 75

Which of the following compounds is chiral?

A) 2-methylpentane
B) 3-ethylhexane
C) 3-methylheptane
D) 4-ethylheptane
E) 3-methylpentane

Question 76

What is the index of hydrogen deficiency in C₉H₁₆Br₂?

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

Question 77

Which of the following compounds exhibits optical isomerism?

A) CH₃-CH₂-CH₃
B) CH₃-CH₂-CHBr-CH₂-CH₃
C) CH₃-CHCl-CH₃
D) CH₃-CH₂-CHBr-CH₃
E) CH₃-CH₂-CBr₂-CH₃

Question 78

Which of the following structures is R-but-3-en-2-ol?

A)
B)
C)
D)
E)

Question 79

Determine the absolute configuration of the molecule shown below:

A) S configuration
B) R configuration
C) E configuration
D) Z configuration
E) d configuration

Question 80

The general formula for alkanes is C_nH_2n+2. What is the value of n in 4-methylethylheptane? Is this molecule chiral?

A) n = 9; yes, it is chiral
B) n = 9; no, it is not chiral
C) n = 10; yes, it is chiral
D) n = 10; no, it is not chiral
E) n = 7; yes, it is chiral