Deck 12: Alkanes

Question 1

What is the IUPAC name of this compound?

A)4-isopentylnonane
B)3-ethyl-4-propylnonane
C)3, 3-dimethyl-4-propylnonane
D)3, 3-dimethyl-4-butylnonane

Answer 1

C

Question 2

What is the IUPAC name of CH₃CH₂CH₂CH₂CH₂CH₃?

A)butane
B)hexane
C)propane
D)pentane
E)heptane

Answer 2

B

Question 3

What is the IUPAC name of this compound?

A)3-ethyl-5-methyldecane
B)3-ethyl-2-pentylhexane
C)3-ethyl-5-pentylhexane
D)8-ethyl-6-methyldecane

Answer 3

A

Question 4

What is the IUPAC name of this compound?

A)ethyl-methyl-cyclopropane
B)ethyl-2-methylcyclobutane
C)1-ethyl-2-methylcyclobutane
D)1-ethyl-2-methylcyclopropane
E)ethyl-2-methylcyclotriane

Question 5

Which formula represents a cyclic alkane?

A)C₁₀H₁₈
B)C₁₀H₂₂
C)C₉H₂₀
D)C₁₀H₂₀
E)C₁₁H₂₀

Question 6

How many hydrogen atoms are present in a cyclic alkane with six (6)carbon atoms?

A)6
B)8
C)10
D)12
E)14

Question 7

Which formula represents an acyclic alkane?

A)C₁₀H₁₈
B)C₉H₁₈
C)C₁₂H₂₆
D)C₁₀H₂₀
E)C₁₂H₂₈

Question 8

Which compound is a constitutional isomer of the one shown below?

A)
B)
C)
D)
E)More than one of the compounds above is a constitutional isomer.

Question 9

Which structure depicts an alkane of molecular formula C₆H₁₂ that has two 1° carbons and two 3° carbons?

A)
B)CH₃CH₂CH₂CH₂CH₂CH₃
C)
D)

Question 10

What is the most preferred arrangement of the atoms in n-pentane?

A)
B)
C)
D)

Question 11

What is the IUPAC name of this compound?

A)4-propylhexane
B)3-ethyl-2-methylhexane
C)2-methyl-3-ethylhexane
D)4-ethyl-5-methylheptane

Question 12

How many hydrogen atoms are present in an acyclic alkane with five (5)carbon atoms?

A)5
B)7
C)9
D)10
E)12

Question 13

How many secondary carbons are in the straight-chain alkane with the formula C₄H₁₀?

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

Question 14

Which of the following is a constitutional isomer of the compound shown below?

A)
B)
C)
D)
E)More than one of the molecules above is a constitutional isomer of the original molecule.

Question 15

Which of the following is a constitutional isomer of the compound shown below?

A)
B)
C)
D)
E)More than one of the molecules above is a constitutional isomer of the original molecule.

Question 16

What is the classification of each labeled carbon atom in the structure below?

A)C1 is a secondary carbon and C2 is a primary carbon.
B)C1 is a tertiary carbon and C2 is a secondary carbon.
C)C1 is a secondary carbon and C2 is a tertiary carbon.
D)C1 is a primary carbon and C2 is a tertiary carbon.

Question 17

Which of the following compounds is identical to the one shown below?

A)
B)
C)
D)

Question 18

How many primary carbon atoms are in the straight-chain alkane with the formula C₃H₈?

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

Question 19

What is the IUPAC name of CH₃CH₂CH₂CH₃?

A)butane
B)methane
C)propane
D)pentane

Question 20

What is the IUPAC name of this compound?

A)4-isopentylnonane
B)3-ethyl-4-propylnonane
C)3, 3-dimethyl-4-propylnonane
D)3, 3-dimethyl-4-butylnonane

Question 21

What is the structure of 2-methylhexane?

A)(CH₃)₂CHCH₂CH₂CH₃
B)(CH₃)₂CHCH₂CH₂CH₂CH₃
C)(CH₃)₃CCH₂CH₂CH₂CH₃
D)

Question 22

Which compound is identical to this molecule?

A)(CH₃)₂CHCH₂CH₂CH₃
B)CH₃(CH₂)₄CH₃
C)
D)
E)More than one molecule is identical to the original molecule.

Question 23

Which name represents a valid IUPAC name for an alkane?

A)1, 4-diethylheptane
B)4, 4-diethyl-2, 3, 4-trimethylpentane
C)4, 4-diethyl-2, 3, 4-trimethylcycloheptane
D)4, 4-diethyl-2, 3-dimethylheptane
E)More than one of the names above is a valid IUPAC name for an alkane.

Question 24

Which has the highest boiling point?

A)natural gas
B)lubricating oil
C)gasoline
D)kerosene
E)fuel oil

Question 25

Which balanced chemical equation represents the incomplete combustion of a hydrocarbon?

A)CH₃CH₂CH₃ + 5 O₂ $\rightarrow$ 3 CO₂ + 4 H₂O
B)2 CH₃CH₂CH₃ + 7 O₂ $\rightarrow$ 6 CO + 8 H₂O
C)C₃₆H₇₄ + 36 O₂ $\rightarrow$ 36 CO + 37 H₂O
D)C₂₆H₅₀ + 33 O₂ $\rightarrow$ 16 CO₂ + 10 CO + 25 H₂O

Question 26

Which name is not a valid IUPAC name for an alkane?

A)2, 3, 4-trimethylhexane
B)1-butyl-2-ethylcyclopentane
C)1-ethyl-2-butylpentane
D)5-butyl-2-methylnonane

Question 27

What is the structure of butylcyclopentane?

A)
B)
C)
D)

Question 28

Which molecule is a constitutional isomer of the compound (CH₃)₂CH(CH₂)₂CH₃?

A)CH₃CH₂CH₂CH(CH₃)₂
B)
C)
D)CH₃CH₂CH₂CH₂CH₃

Question 29

What is the classification of each labeled carbon atom in this structure?

A)C1 is a 1°, C2 is 2°, C3 is a 3°, and C4 is 4°.
B)C1 is a 2°, C2 is 3°, C3 is a 3°, and C4 is 4°.
C)C1 is a 1°, C2 is 2°, C3 is a 3°, and C4 is 1°.
D)C1 is a 2°, C2 is 3°, C3 is a 2°, and C4 is 3°.

Question 30

Which alkane has the lowest boiling point?

A)octane
B)butane
C)ethane
D)hexane
E)propane

Question 31

What is the IUPAC name of this molecule?

A)2, 4-dimethyl-2-ethylhexane
B)2-ethyl-2, 4-dimethylhexane
C)3, 3, 5-trimethylheptane
D)5-ethyl-3, 5-dimethylhexane

Question 32

How many secondary carbons are in the molecule (CH₃)₂CH(CH₂)₂CH₃?

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

Question 33

Which compound has the lowest melting point?

A)CH₃CH₂CH₂CH₂CH₃
B)CH₃CH₂CH₂CH₂CH₂CH₂CH₂CH₃
C)CH₃CH₂CH₂CH₂CH₂CH₃
D)CH₃CH₂CH₂CH₂CH₂CH₂CH₂CH₂CH₂CH₃

Question 34

What is the structure of 2-methylhexane?

A)(CH₃)₂CHCH₂CH₂CH₃
B)(CH₃)₂CHCH₂CH₂CH₂CH₃
C)(CH₃)₃CCH₂CH₂CH₂CH₃
D)

Question 35

How many tertiary carbons are in the molecule (CH₃)₂CH(CH₂)₂CH₃?

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

Question 36

What is the structure of butylcyclopentane?

A)
B)
C)
D)

Question 37

How many quaternary carbons are in this molecule?

A)0
B)1
C)4
D)5

Question 38

Which molecule is a constitutional isomer of the compound (CH₃)₂CH(CH₂)₂CH₃?

A)CH₃CH₂CH₂CH(CH₃)₂
B)
C)
D)

Question 39

What is the classification of each labeled carbon atom in this structure?

A)C1 is a 1°, C2 is 2°, C3 is a 3°, and C4 is 4°.
B)C1 is a 2°, C2 is 3°, C3 is a 3°, and C4 is 4°.
C)C1 is a 1°, C2 is 2°, C3 is a 3°, and C4 is 1°.
D)C1 is a 2°, C2 is 3°, C3 is a 2°, and C4 is 3°.

Question 40

How many polar bonds are in this molecule?

A)0
B)1
C)2
D)14

Question 41

Asphalt is a mixture of high molecular weight hydrocarbons. Which solvent would be best for removing asphalt from a newly paved road off the bottom of a pair of shoes?

A)water
B)octane
C)methanol, CH₃OH
D)NaCl(aq)

Question 42

The combustion of alkanes and other hydrocarbons obtained from fossil fuels adds a tremendous amount of CO₂ to the atmosphere each year.

Question 43

CO₂ is a greenhouse gas.

Question 44

Which of the following pairs of compounds are constitutional isomers?

A)
B)
C)
D)

Question 45

The products of the complete combustion of any hydrocarbon are CO₂ + H₂O, regardless of the identity of the starting material.

Question 46

Eicosane has the structure: CH₃(CH₂)₁₈CH₃. What does the prefix eicos specifically indicate about the structure of this compound?

A)It contains a straight chain of carbons.
B)It contains 20 carbons in a continuous chain.
C)It is an alkane.
D)It is a saturated hydrocarbon.

Question 47

The IUPAC name of the molecule (CH₃)₂CH(CH₂)₂CH₃ is 2-methylhexane.

Question 48

Which is NOT a property associated with tetradecane, a 14-carbon straight chain alkane?

A)strong hydrogen bonds
B)low water solubility
C)density less than water
D)flammable liquid

Question 49

Which molecular formula has the largest number of constitutional isomers?

A)C₅H₁₂
B)C₂H₆
C)C₆H₁₄
D)All of the molecular formulas above have the same number of constitutional isomers.

Question 50

Which of the following pairs of compounds are constitutional isomers?

A)
B)(CH₃)₃CCl and (CH₃)₃CBr
C)
D)

Question 51

Alkanes containing only secondary carbon atoms do not exist.

Question 52

A branched alkane and a cycloalkane with the same number of carbons have the same number of hydrogen atoms in their chemical formulas.

Question 53

What is the classification of the carbon atom that bonded to the -OH group in menthol?

A)primary
B)secondary
C)tertiary
D)quaternary

Question 54

All organic molecules must have at least one primary carbon atom.

Question 55

Branching in an alkane chain decreases surface area. With this in mind, which of the following alkanes has the highest boiling point?

A)(CH₃)₂CHCH₂CH₂CH₂CH₂CH₃
B)(CH₃)₂CHCH₂CH₂CH(CH₃)₂
C)CH₃CH₂CH₂CH₂CH₂CH₂CH₂CH₃
D)(CH₃)₃CC(CH₃)₃

Question 56

Shark liver oil is approximately 14% pristane (C₁₉H₄₀). Pristane is an acyclic alkane.

Question 57

Which compound is identical to this molecule?

A)(CH₃)₂CHCH₂CH₂CH₃
B)CH₃(CH₂)₄CH₃
C)CH₃CH₂CH(CH₃)₂
D)CH₃(CH₂)₂CH(CH₃)₂
E)More than one molecule is identical to the original molecule.

Question 58

The molecules below are constitutional isomers.

Question 59

The compounds below are constitutional isomers.

Question 60

What is the classification of the carbon atom that bonded to the -OH group in menthol?

A)primary
B)secondary
C)tertiary
D)quaternary

Question 61

The compounds below are constitutional isomers.

Question 62

If a cyclic alkane has 28 hydrogens and a single ring, it must have 13 carbon atoms.

Question 63

The compounds below are identical.

Question 64

Cyclic alkanes are planar molecules containing one or more rings of carbon.

Question 65

The two structures below represent the same compound.

Question 66

The two structures below represent the same compound.

Question 67

The IUPAC name of the molecule below is butylcyclopentane.

Question 68

The IUPAC name of the molecule below is butylcyclopentane.

Question 69

The compounds below are identical.

Question 70

C₂H₆ has a higher boiling point than the compound below.

Question 71

The molecular formula for an alkane with 12 carbon atoms and two rings is C₁₂H₂₄.

Question 72

The molecule below contains 1°, 2°, and 3°carbon atoms, but no 4° carbon atoms.

Question 73

Natural gas is composed primarily of propane.

Question 74

The compounds below are constitutional isomers.

Question 75

Pentane has a higher boiling point than 2, 2-dimethylpropane.

Question 76

Oxidation results in a decrease in the number of C-O bonds and an increase in the number of C-H bonds.

Question 77

The compounds below are constitutional isomers.

Question 78

The compounds below are constitutional isomers.

Question 79

Acyclic alkanes with four or more carbon atoms have constitutional isomers.

Question 80

The compounds below are constitutional isomers.