Deck 13: Organic Chemistry: Fuels, Pharmaceuticals, and Materials

Question 1

Iso-octane has the following structure. In this structure, how many carbon atoms are bonded to three other carbon atoms?

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

Answer 1

1

Question 2

A saturated compound composed solely of carbon and hydrogen must be __________

A) an alkane.
B) an alkene.
C) an alkyne.
D) either an alkane or an alkene.
E) either an alkene or an alkyne.

Answer 2

an alkane.

Question 3

A subunit of an organic compound that confers particular chemical and physical properties is termed __________

A) a monomer.
B) an oligomer.
C) a functional group.
D) a synthetic unit.
E) an isomer.

Answer 3

a functional group.

Question 4

Organic chemistry encompasses the chemistry of all __________

A) hydrocarbons.
B) functional groups.
C) monomers, oligomers, and polymers.
D) naturally occurring compounds.
E) carbon compounds.

Question 5

Where is the carbon-carbon double bond in the hydrocarbon shown?

A) on the left
B) in the middle
C) on the right
D) on each bond
E) spread over all three bonds because of resonance

Question 6

Which of the following are true regarding cyclohexane, whose carbon skeleton is shown?
(I) The molecule is flat.
(II) Each carbon is bonded to four other atoms.
(III) Each carbon is sp³ hybridized.

A) I only
B) II only
C) III only
D) II and III only
E) I, II, and III are all true.

Question 7

Which is not true about n-alkanes?

A) Their formulas are all C_nH_2n+2.
B) All of the carbon atoms are centers of tetrahedral geometry.
C) Their melting points increase with the number of carbon atoms.
D) Their vapor pressures increase with the number of carbon atoms.
E) All of the carbons are sp³ hybridized.

Question 8

What is the molecular formula for the compound illustrated below?

A) C₅H₈
B) C₅H₉
C) C₅H₁₀
D) C₅H₁₁
E) C₅H₁₂

Question 9

The basic building block of a polymer is called ___________

A) a functional group.
B) a monomer.
C) a monotone.
D) an oligomer.
E) an addition.

Question 10

Which of the following is true about normal alkanes?

A) They all exhibit strong hydrogen bonding with one another and with water.
B) They all contain carbon, hydrogen, and oxygen in consistent ratios.
C) Some are gases, some are liquids, and some are solids at room temperature.
D) Some are yellow, some are red, and some are blue, depending on the chain length.
E) They have the formula C_nH_2n+2 if they are linear or branched or C_nH_2n if they are cyclic.

Question 11

A compound composed solely of carbon and hydrogen that is unsaturated must be __________

A) an alkane.
B) an alkene.
C) an alkyne.
D) either an alkane or an alkene.
E) either an alkene or an alkyne.

Question 12

The C - C - C bond angles in octane (CH₃CH₂CH₂CH₂CH₂CH₂CH₂CH₃) are ___________

A) 180°.
B) 120°.
C) 90°.
D) 109.5°.
E) 60°.

Question 13

A hydrocarbon is a compound that contains __________

A) carbon with hydrogen and oxygen in the ratio 2:1.
B) carbon with hydrogen and oxygen in any ratio.
C) only carbon and hydrogen.
D) carbon, hydrogen, and any functional groups.
E) carbon and any other elements.

Question 14

The -CH₂- unit is known as

A) a methyl group.
B) a methylene group.
C) an acetylene group.
D) an alkyne group.
E) an alkene group.

Question 15

Which of the following is not likely to be a component of a natural gas deposit?

A) CH₄
B) C₃H₈
C) C₄H₈
D) C₄H₁₀
E) C₈H₁₈

Question 16

What is the degree of unsaturation of CH₂ CH - C CH?

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

Question 17

When 1 mol of an alkene with one degree of unsaturation is hydrogenated, how many moles of hydrogen gas react?

A) 0 mol
B) 1.5 mol
C) 0.5 mol
D) 1.0 mol
E) 2.0 mol

Question 18

Which of the following is a methyl group?

A) -CH₂
B) =CH₂
C) -CH₂-
D) =CH=
E) -CH₃

Question 19

Which of the following tends to be true of polymers but not small molecules?
(I)Variable instead of constant composition
(II)A poorly defined melting point
(III)Solid state regions that are disordered

A) I
B) II
C) III
D) I, II, and III
E) None of these, as polymers are molecules just like small molecules only bigger.

Question 20

Which of the following structures is an unsaturated hydrocarbon?

A)
B)
C)
D)

Question 21

Consider the 1,2-dichloro derivative of ethylene in which one of the hydrogen atoms on each of the carbon atoms in ethylene is substituted with a chlorine atom, giving the structural formula CHClCHCl. Which of the following is true?

A) The cis isomer is more polar.
B) The trans isomer is more polar.
C) Neither cis nor trans isomers are polar.
D) Both cis and trans isomers are equally polar.
E) There are no isomers for this molecule.

Question 22

What is the molecular formula for the following compound?

A) C₄H₅O₂
B) C₄H₆O₂
C) C₄H₇O₂
D) C₄H₈O₂
E) C₄H₁₀O₂

Question 23

Name the compound.

A) 1-butene
B) 1-butyne
C) 2-butene
D) 2-butyne
E) butane

Question 24

Which of the following pairs has the same molecular formula?

A) hexene and cyclohexane
B) octane and cyclooctane
C) hexane and benzene
D) hexane and cylcohexene
E) methyl and methylene

Question 25

For each of the bonds in the figure below, identify whether the bond is cis, trans, or neither cis nor trans.

A) I-cis; II-trans; III-cis
B) I-trans; II-cis; III-trans
C) I-neither; II-trans; III-cis
D) I-neither; II-cis; III-trans
E) I-neither; II-cis; III-cis

Question 26

What is the formula for n-nonane?

A) CH₃(CH₂)₉CH₃
B) CH₃(CH₂)₇CH₃
C) CH₃(CH₂)₁₇CH₃
D) CH₃(CH₂)₅CH₃
E) CH₃(CH₂)₈CH₃

Question 27

What is the molecular formula for the following compound?

A) C₆H₁₁
B) C₆H₁₂
C) C₇H₁₁
D) C₇H₁₂
E) C₇H₁₄

Question 28

Without working out all the structures, which has the larger number of structural isomers, C₁₄H₃₀ or C₁₅H₃₂?

A) C₁₄H₃₀
B) C₁₅H₃₂
C) They have the same number of isomers.
D) There is no way to tell without working out all the structures.

Question 29

Name this molecule.

A) dodecane
B) cyclohexane (boat conformation)
C) cyclohexane (chair conformation)
D) puckerane
E) trans-cyclohexane

Question 30

Cyclic alkanes differ from normal alkanes in ___________

A) the ratio of hydrogen to carbon.
B) their utility as a combustible fuel.
C) the orbital hybridization on the carbon atoms.
D) the number of hydrogens bonded to non-terminal carbon atoms.
E) the degree to which electrons are delocalized.

Question 31

Most simple ionic compounds that are soluble in water are not soluble in organic solvents. However, replacing a common cation such as Na⁺ with an alkyl ammonium ion with four alkyl groups greatly enhances solubility of the ionic compound in many organic solvents. Which formula represents the tetrabutylammonium ion that is found in tetrabutylammonium bromide?

A) [(CH₃)₄N]⁺
B) [(CH₃CH₂)₄N]⁺
C) [(CH₃(CH₂)₂)₄N]⁺
D) [(CH₃(CH₂)₃)₄N]⁺
E) [C(CH₃)₃NH₂]⁺

Question 32

Does this molecule have both cis and trans isomers?

A) Yes, this is the cis isomer.
B) Yes, this is the trans isomer.
C) No, it has only the cis isomer.
D) No, it has only the trans isomer.
E) No, this molecule does not have cis-trans isomerism.

Question 33

Name the compound.

A) cis-3-octene
B) trans-3-octene
C) cis-5-octene
D) trans-5-octene
E) 1-ethyl-2-butyl ethylene

Question 34

What is the molecular formula for the compound illustrated below?

A) C₅H₇
B) C₅H₈
C) C₅H₉
D) C₅H₁₀
E) C₅H₂₃

Question 35

A molecule with the formula C₇H₁₄ was found to have carbons that were all identical in terms of structure. That is, each carbon atom was bonded to exactly the same kinds of atoms as all the rest. What is a reasonable structure for this molecule?

A) CH₃(CH₂)₅CH₃
B)
C) CH₂(CH₂)₅CH₂
D)

Question 36

Consider the 1,2-dichloro derivative of ethylene in which one of the hydrogen atoms on each of the carbon atoms in ethylene is substituted with a chlorine atom, giving the structural formula CHClCHCl. Does this molecule have geometrical isomers? Remember that ethylene does not.

A) yes, because the chlorines can be placed on the same or opposite sides of the double bond
B) yes, because the chlorines can be placed on either one or both of the carbons
C) no, because both the formula and bonds are the same in all skeletal structures
D) no, because the two structures can interconvert through bond rotation
E) no, because there are less than four atoms bound to each carbon

Question 37

Crude oil is composed mostly of

A) liquefied carbon.
B) liquefied rock and soil.
C) compounds composed of carbon and hydrogen.
D) decomposed anaerobic bacteria.
E) compounds composed of carbon, hydrogen, oxygen, and nitrogen.

Question 38

How many structural (constitutional) isomers are there for propylene, and why?

A) two, because of resonance
B) two, because of geometrical isomerism
C) two, because the double bond can be in either one of two locations
D) none, because the two skeletal structures can be superimposed
E) none, because double bonds always occur on the right in alkenes

Question 39

Name the compound with the structural formula CH₃(CH₂)₁₆CH₃.

A) n-octane
B) n-hexadecane
C) n-octadecane
D) n-decane
E) 1,16-dimethylhexadecane

Question 40

What is the systematic name of the molecule shown?

A) 2,2,3,4-tetramethylpentane
B) 2,3,4,4-tetramethylpentane
C) 1,2,3,4,4-pentamethylbutane
D) 1,1,1,2,3,3-hexamethylpropane
E) 2-tert-butyl-3-methylbutane

Question 41

How many structural isomers does toluene (C₆H₅CH₃) have?

A) None, i.e., there is only 1 molecule
B) 2
C) 3
D) 4
E) 5

Question 42

The monomer for polystyrene is shown below. Which of the bonds is involved in the polymerization process?

A) I only
B) II only
C) III only
D) IV only
E) Bonds I-IV are all involved in polymerization.

Question 43

Which of the following shows a small section of polyethylene?

A)
B)
C)
D)
E)

Question 44

The Aldrich Chemical Company catalogue lists the three isomers of xylene as having boiling points of 143-145°C, 138-139°C, and 138°C. Which isomer has the highest boiling point, and why?

A) o-xylene (1,2-dimethylbenzene) because of its polarity
B) p-xylene (1,4-dimethylbenzene) because of its polarity
C) p-xylene (1,4-dimethylbenzene) because of its para-normalcy
D) m-xylene (1,3-dimethylbenzene) because of its C₂ symmetry
E) o,m,p-xylene (1,2,3,4-tetramethylbenzene) because of its molar mass

Question 45

Name the compound.

A) 3-methyl-6-heptene
B) 5-ethyl-1-hexene
C) 5-methyl-1-heptene
D) 2-ethyl-5-hexene
E) 3-methylpentylethylene

Question 46

What functional group is found in the following molecule?

A) amine
B) amide
C) ammonia
D) ammonium
E) amonyl

Question 47

Name the compound.

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

Question 48

How many structural isomers does xylene have?

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

Question 49

Naphthalene, a polyaromatic hydrocarbon, is used for mothballs. Its molecular formula is C₁₀H₈. How many fused aromatic rings does naphthalene have in its molecular structure?

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

Question 50

A homopolymer is a polymer in which ___________

A) each polymer has the same mass.
B) each polymer has the same mass and structure.
C) the monomers are distributed uniformly throughout the polymer.
D) the polymers are distributed uniformly throughout the solution.
E) there is only one monomer unit.

Question 51

Which of the following is not a difference between cyclohexane and benzene?

A) Cyclohexane is puckered, but benzene is planar.
B) Cyclohexane carbons are sp³ hybridized, but benzene carbons are sp² hybridized.
C) Cyclohexane is a combustible hydrocarbon, but benzene has such a stable aromatic structure that it does not burn.
D) Cyclohexane has 12 hydrogen atoms in its structure, but benzene has 6 hydrogen atoms in its structure.
E) Cyclohexane is not aromatic, but benzene is.

Question 52

What type of amine is adrenaline, which is depicted below?

A) aromatic
B) auxiliary
C) primary
D) secondary
E) tertiary

Question 53

Are the methyl groups in xylene included in the aromatic part of the molecular structure?

A) Yes, the aromatic bonding extends throughout the molecule.
B) Yes, but only when the resonance form with double bonds to the methyl groups exists.
C) No, only the carbons in the ring are involved in aromatic bonding.
D) No, only the hydrogens in the ring are involved in the aromatic bonding.
E) No, only the carbon atoms in xylene are involved in aromatic bonding, not the hydrogens.

Question 54

Which of the following is/are true regarding aromatic hydrocarbons?
(I)They are particularly stable because of delocalized bonding.
(II)They are particularly stable because of their covalent network bonding.
(III)They are particularly unstable as evidenced by their tendency to evaporate.

A) I only
B) II only
C) III only
D) I and II only
E) I and III only

Question 55

Which of the following monomers is used in making the polymer illustrated below?

A)
B)
C)
D)
E)

Question 56

Do carbon atoms in aromatic hydrocarbon molecules (not ions) obey the octet rule?

A) No, each carbon is bonded to only three atoms, and there are no lone pairs.
B) No, each carbon has one single bond and one double bond for a total of only six electrons.
C) Yes, each carbon obeys the octet rule.
D) Yes, but only because the double bond is counted twice owing to the resonance structures.
E) Yes, but only when one or the other resonance form dominates, not when the structure is an average of the two.

Question 57

Which of the following structures represents cyclohexene?

A)
B)
C)
D)

Question 58

Delocalized bonding in aromatic hydrocarbons is possible because of ___________

A) the fact that electrons can move very quickly from one resonance form to another.
B) adjacent 2p_z orbitals each having one electron.
C) Wade's rules.
D) double-headed arrows.
E) Cooper pairs.

Question 59

What is another name for methylbenzene?

A) toluene
B) xylene
C) naphthalene
D) Jolene
E) 1-methyl-2,4,6-cyclohexene

Question 60

Which of the following is an amine functional group?

A) -COOH
B) -OH
C) -NH
D) -NH₂
E) -CONH₂

Question 61

The alcohol functional group has the bonding arrangement ___________

A) C -O -H.
B) C -O -C.
C) Al -O -H.
D) C -O -O -H.
E) R -O -H, where R is any element.

Question 62

Rank the following according to their fuel values in order of increasing energy/mass. C₈H₁₈; CO; CH₃OH; CH₃OCH₃

A) CO < CH₃OCH₃ < CH₃OH < C₈H₁₈
B) CH₃OCH₃ < CO < CH₃OH < C₈H₁₈
C) CO < CH₃OH < CH₃OCH₃ < C₈H₁₈
D) C₈H₁₈ < CO < CH₃OH < CH₃OCH₃
E) C₈H₁₈ < CH₃OCH₃ < CH₃OH < CO

Question 63

Which functional group is found in the following molecule?

A) alcohol
B) aldehyde
C) carbonyl
D) ester
E) ether

Question 64

What functional group is found in the following molecule?

A) alcohol
B) aldehyde
C) aquo
D) carbonyl
E) hydroxyl

Question 65

Which of the following illustrates the aldehyde functional group?

A)
B)
C)
D)
E) All of the above illustrate the aldehyde functional group.

Question 66

The characteristic "fishy" odor comes from methylamine (CH₃NH₂), which is similar to ammonia (NH₃) in structure and also in its ability to react with acids as a weak base. Why would the acid form of methylamine not have as strong an odor as methylamine?

A) because it would decompose to methane and ammonia
B) because it would not be volatile as a polyatomic ion
C) because it would melt in the acid
D) because it would decompose to carbon, hydrogen, and nitrogen
E) because it would have a different three-dimensional structure

Question 67

MTBE (methyl tert-butyl ether) is:

A)
B)
C)
D)

Question 68

Gasoline additives like ethanol are employed to

A) decrease odor.
B) promote complete combustion.
C) decrease octane rating.
D) make the fuel less volatile.
E) increase fuel value.

Question 69

Which of the following class of compounds is not used in gasoline?

A) alcohols
B) ethers
C) thiols
D) alkanes
E) octanes

Question 70

Rank these molecules with respect to the increasing oxidation number of the carbon atom: formic acid (HCOOH); methane (CH₄); methanol (CH₃OH); carbon dioxide (CO₂); graphite (C).

A) formic acid; carbon dioxide; methanol; methane; graphite
B) methanol; methane; graphite; carbon dioxide; formic acid
C) methane; methanol; graphite; formic acid; carbon dioxide
D) carbon dioxide; formic acid; graphite; methanol; methane
E) The oxidation number of carbon is the same in all of these compounds.

Question 71

Which of these functional groups does not contain a carbonyl group?

A) aldehyde
B) carboxylic acid
C) ester
D) ether
E) ketone

Question 72

Which functional group is found in the following molecule?

A) aldehyde
B) carboxylic acid
C) ester
D) ether
E) ketone

Question 73

Methane used for fuel and commonly called natural gas is odorless, but for safety it has a small quantity of foul-smelling methylmercaptan (CH₃SH) added. The "mercaptan" functional group is most similar to which of the following?

A) carboxylic acid
B) amine
C) alcohol
D) aldehyde
E) ether

Question 74

Which functional group is found in the following molecule?

A) aldehyde
B) carboxylic acid
C) ester
D) ether
E) ketone

Question 75

Alcohols used as a gasoline additive or substitute are often called biofuels. Similar organic compounds derived from vegetable oils and fats are called biodiesels, which are not alcohols but another class of organic chemicals called esters. Qualitatively compare the combustion energy content (kJ/g) of the four-carbon alcohol, butanol (CH₃CH₂CH₂CH₂OH), with the energy content (kJ/g) of the four-carbon ester, ethyl acetate (CH₃COOCH₂CH₃).

A) Ethyl acetate has less energy/mass than butanol.
B) Ethyl acetate has more energy/mass than butanol.
C) The two compounds have roughly the same energy/mass.
D) These are not two different compounds and so must have the same energy/mass.
E) There is no basis for determining this without some form of enthalpy values.

Question 76

The C - O - C bonding arrangement is called the _____ functional group.

A) alcohol
B) ester
C) amine
D) ether
E) carbonyl

Question 77

In the following structure of tert-butyl alcohol, identify the tertiary carbon.

A) C3
B) C4
C) C5
D) C6
E) C8

Question 78

Ethanol is a renewable chemical energy source, but there are presently some barriers to its use as the primary fuel for cars. Which of the following is not among these barriers?

A) It is more expensive than gasoline.
B) It has a lower fuel value than gasoline.
C) Much of the energy it can produce is expended in its production.
D) It is a greater contributor to global warming than gasoline because it produces more carbon dioxide per carbon atom than gasoline.
E) All of the above are barriers to its use as a primary fuel.

Question 79

Which of the following is the ketone functional group?

A)
B)
C)
D)
E) All of the above illustrate the ketone functional group.

Question 80

Ethanol is water soluble. Which of the following sketches properly illustrates the strongest interaction between water and ethanol that is responsible for this solubility?

A)
B)
C)
D)