Deck 6: Organic Chemistry: Hydrocarbons

Question 1

Which of the following compounds is inorganic?

A) CH₄O
B) CH₄
C) CO₂
D) NH₃
E) CH₂O

Answer 1

NH₃

Question 2

Which of the following foods should be avoided in order to limit the consumption of saturated fat?

A) whole milk
B) cheese
C) ice cream
D) red meat
E) All of the above

Answer 2

All of the above

Question 3

Which of the following compounds contains a heteroatom?

A) All of these compounds contain a heteroatom.
B) I and II contain a heteroatom.
C) III and IV contain a heteroatom.
D) Only III contains a heteroatom.
E) I, II, and III contain a heteroatom.

Answer 3

I and II contain a heteroatom.

Question 4

A hydrocarbon contains

A) only carbon, hydrogen, nitrogen and oxygen.
B) only carbon and hydrogen.
C) only carbon, hydrogen, and oxygen.
D) only carbon, hydrogen, and nitrogen.
E) any element except carbon and hydrogen.

Question 5

A compound with the molecular formula C_nH_2n+2 is called a(n)______or a ______.

A) alkane, saturated hydrocarbon
B) alkane, unsaturated hydrocarbon
C) alkene, saturated hydrocarbon
D) alkene, unsaturated hydrocarbon
E) alkene, alkyne

Question 6

Which of the following is a saturated hydrocarbon?

A) C₃H₆
B) C₆H₆
C) C₄H₆
D) C₄H₁₀
E) C₂H₄

Question 7

Which of the fatty acids are saturated?

A) All of them are saturated.
B) Only B and C are saturated.
C) Only A, D, and E are saturated.
D) A, D, B, and E are saturated.
E) None of them are saturated.

Question 8

An alkene has _______ a saturated hydrocarbon with the same number of hydrogens.

A) two more hydrogens than
B) one more hydrogen than
C) the same number of hydrogens as
D) one fewer hydrogen than
E) two fewer hydrogens than

Question 9

A molecule has the molecular formula C₅H₁₀. This molecule could be a(n) ______ and a(n) _____.

A) alkane, saturated hydrocarbon
B) alkane, unsaturated hydrocarbon
C) alkene, saturated hydrocarbon
D) alkene, unsaturated hydrocarbon.
E) alkene, alkyne.

Question 10

Which of these fatty acids is considered a "good fat"?

A) None because all fats are bad
B) All of them because all fats taste good
C) B and E because the higher the molecular weight, the better the fat is
D) C and B because these molecules contain cis double bonds
E) A, D, and E because these molecules do not contain any double bonds

Question 11

Which of the following compounds is a valid Lewis structure of a hydrocarbon?

A) All of these compounds are valid structures of hydrocarbons.
B) I, II, and IV are valid structures of hydrocarbons.
C) III and IV are valid structures of hydrocarbons.
D) Only III is a valid structure of hydrocarbons.
E) Only IV is a valid structure of hydrocarbons.

Question 12

Which of the following statements describes why "good fats" are considered good and "bad fats" are considered bad?
I. A diet high in saturated fat can result in heart disease.
II. A diet high in unsaturated fat can result in type 2 diabetes.
III. A diet high is trans fats can result in a decreased risk of cancer.
IV. A diet high in unsaturated fats can result in a decreased risk of cancer

A) All of these statements are true.
B) I and II are true.
C) I, III, and IV are true.
D) I and IV are true.
E) II and III are true.

Question 13

Which of the following elements is NOT a heteroatom?

A) carbon
B) sulfur
C) nitrogen
D) oxygen
E) phosphorous

Question 14

Which of these fatty acids is an oil at room temperature?

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

Question 15

Which of the hydrocarbons listed are unsaturated? I. alkane
II) alkene
III) alkyne
IV) aromatic

A) alkanes only
B) alkenes and alkynes only
C) alkenes, alkynes, and adromatics
D) alkanes, alkenes, alkynes, and aromatics
E) aromatics only

Question 16

Why do saturated fats have higher melting points than unsaturated fats?

A) Saturated fats stack better than unsaturated fats and therefore have more dispersion forces between them.
B) Saturated fats stack better than unsaturated fats and therefore have fewer dispersion forces between them.
C) Unsaturated fats stack better than saturated fats and therefore have more dispersion forces between them.
D) Unsaturated fats stack better than saturated fats and therefore have fewer dispersion forces between them.
E) Actually, saturated fats have lower melting points than unsaturated fats.

Question 17

Organic chemistry is the study of compounds that

A) are biologically important.
B) contain oxygen.
C) make up living things.
D) are not harmful to the environment.
E) contain carbon.

Question 18

Which terms from this list best describe the following compound?
I. alkane
II. alkene
III. alkyne
IV. aromatic
V. saturated hydrocarbon
VI. unsaturated hydrocarbon

A) I and V
B) II and VI
C) III and VI
D) II and V
E) III and V

Question 19

Which statement best describes the solubility of hydrocarbons?

A) Hydrocarbons are soluble in water and therefore hydrophobic.
B) Hydrocarbons are insoluble in water and therefore hydrophobic.
C) Hydrocarbons are soluble in water and therefore hydrophilic.
D) Hydrocarbons do not dissolve in any solvent.
E) It is not possible to generalize the solubility of hydrocarbons.

Question 20

Which of the following compounds is a saturated hydrocarbon?

A) I only
B) I and II
C) IV only
D) III and IV
E) All of these are saturated hydrocarbons.

Question 21

Which carbon is the branching carbon in the following molecule?

A) a
B) b
C) c
D) d
E) e

Question 22

Which of the following is NOT a goal of naming in the IUPAC system?

A) Each structure should have one name.
B) Each name should represent one structure.
C) It should be possible to draw a chemical structure given the name.
D) It should be possible to name any given structure.
E) The name should indicate something about the purpose of the molecule.

Question 23

Below is an illustration of a molecule of cyclohexane. Which of the following choices best describes why this illustration does not represent cyclohexane accurately?

A) The molecule illustrated does not contain enough carbons.
B) The molecule illustrated contains too many carbons.
C) The molecule illustrated is not saturated.
D) The molecule illustrated is flat.
E) The molecule illustrated is puckered.

Question 24

How many hydrogens are bonded to the carbons with the arrows pointing to them?

A) carbon 1: 0 carbon 2: 0
B) carbon 1: 0 carbon 2: 2
C) carbon 1: 1 carbon 2: 2
D) carbon 1: 4 carbon 2: 4
E) It is not possible to tell given the skeletal line structure.

Question 25

Which of the following structures is heptane?

A)
B)
C)
D)
E)All of these are heptane

Question 26

How do IUPAC names differ from the brand names of pharmaceuticals?

A) IUPAC names are systematic and brand names are not.
B) Brand names are systematic and IUPAC names are not.
C) IUPAC names are usually shorter than brand names.
D) Brand names are not used as frequently as IUPAC names.
E) IUPAC names do not follow a set of rules like brand names do.

Question 27

Which of the following skeletal line structures best represents the Lewis structure below?

A)
B)
C)
D)
E)

Question 28

What is the name of the following cycloalkane?

A) pentane
B) cyclopentane
C) butane
D) cyclobutane
E) cycloalkane

Question 29

Is the following cycloalkane more or less abundant in nature than cyclohexane?

A) more abundant because it is smaller
B) more abundant because it is more stable
C) less abundant because it is substituted
D) less abundant because the bond angles are not 109.5°
E) more abundant because it is substituted

Question 30

Which of the following statements best describes alkanes?

A) They are hydrocarbons.
B) They contain only C-C single bonds.
C) They take on a regular zig-zag shape.
D) They are hydrophobic.
E) All of the above

Question 31

Which of the following condensed structures best represents the skeletal line structure below?

A)
B)
C)
D)
E)

Question 32

What is the IUPAC name of the following hydrocarbon?

A) propane
B) propene
C) butane
D) pentene

Question 33

Which of the following structures is a branched-chain hydrocarbon?

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

Question 34

Which of the following statements about alkanes is NOT true?

A) Alkanes can move and twist.
B) Merely rotating a C-C bond does not change the identity of an alkane.
C) Alkanes are hydrophilic.
D) Alkanes more rapidly twist and rotate at higher temperatures.
E) Alkanes are often found in a zig-zag shape.

Question 35

Which of the following structures is nonane?

A)
B)
C)
D)
E)

Question 36

Which skeletal line structure is the same molecule as the ball-and-stick model below?

A)
B)
C)
D)
E)

Question 37

Which of the following skeletal line structures has the molecular formula C₅H₈?

A)
B)
C)
D)
E)None of these structureshas the molecular formula C₅H₈

Question 38

What is the IUPAC name of the following hydrocarbon?

A) propane
B) butane
C) pentane
D) but-1-ene
E) pent-1-ene

Question 39

Which skeletal line structure is the same molecule as the ball-and-stick model below?

A)
B)
C)
D)
E)

Question 40

Which of the following structures is the best condensed structural formula for the Lewis structure given below?

A)
B)
C)
D)
E)

Question 41

How many hydrogens are attached to the carbons indicated below?

A) C1: 2 C2: 0
B) C1: 0 C2: 2
C) C1: 1 C2: 1
D) C1: 0 C2: 1
E) C1: 1 C2: 0

Question 42

What is the molecular shape around the carbon indicated with an arrow?

A) linear
B) trigonal pyramidal
C) tetrahedral
D) bent
E) trigonal planar

Question 43

Which of the molecules below are branched? I II III IV

A) I only
B) II and IV
C) II, III, and IV
D) I and III
E) All of these molecules are branched.

Question 44

Which structures are straight chain hydrocarbons? I II III IV

A) I only
B) II and IV
C) II, III, and IV
D) I and III
E) All of these molecules have a straight chain.

Question 45

Below is illustrated a molecule of butane. Which of the given choices is another molecule of butane in a different conformation? Assume that all atoms in each are visible. Butane

A)
B)
C)
D)
E)

Question 46

Which statement best describes the relationship between the following two structures?

A) They are identical.
B) They have different molecular formulas.
C) They are isomers.
D) They are conformers.
E) One is an alkene and the other is an alkyne.

Question 47

β-Carotene is the molecule that gives carrots their orange color. Which characteristic of β-carotene is primarily responsible for the orange color?

A) the branched-chain
B) the two cyclohexanes
C) the conjugated alkenes
D) the trans geometry
E) the number of carbons

Question 48

Which statement best describes the relationship between the following two structures?

A) They are identical.
B) They have different molecular formulas.
C) They are isomers.
D) They are conformers.
E) One is an alkene and the other is an alkyne.

Question 49

What type of alkene is boxed in lovastatin, a drug used to control cholesterol levels?

A) A diene that is not conjugated
B) A conjugated diene
C) A polyene that is not conjugated
D) A conjugated polyene
E) This molecule does not contain an alkene.

Question 50

Which of the molecules below are structural isomers? I II III IV

A) I and II
B) I and IV
C) I, III, and IV
D) I and III
E) All of these are structural isomers.

Question 51

Are the following two molecules structural isomers?

A) No, because they do not have the same molecular formula
B) Yes, because they have the same molecular formula but different structures
C) Yes, because they have the same number of carbons
D) Yes, because they do not have the same molecular formula
E) No, because only one is branched

Question 52

Which of the following molecules contains a conjugated polyene?

A)
B)
C)
D)
E) All of these contain a conjugated polyene

Question 53

How many carbon atoms are in a molecule of estradiol, the steroid shown below?

Question 54

Which statement best describes the relationship between the following two structures?

A) They are identical.
B) They have different molecular formulas.
C) They are isomers.
D) They are conformers.
E) One is an alkene and the other is an alkyne.

Question 55

Which of the following skeletal line structures represent the same molecule?

A) I and II
B) II and III
C) I, II, IV, and V
D) IV and V
E) II, IV, and V

Question 56

Which of these structures below are conformers? I II III IV

A) I and II
B) I and IV
C) I, III, and IV
D) I and III
E) All of these are conformers.

Question 57

Which of the following definitions best describes structural isomers?

A) They are molecules with different structures.
B) They are molecules with the same molecular formula and the same structure.
C) They are molecules with the same physical properties.
D) They are molecules that have the same molecular formula but different structures.
E) They are molecules that look similar.

Question 58

Which of the following skeletal line structures are isomers? I. II. III. IV.

A) All of these are isomers.
B) I and II
C) I, II, and III
D) III and IV
E) II and III

Question 59

Which of the following structures represents a diene?

A)
B)
C)
D)
E)

Question 60

How many hydrogen atoms are in the following structure?

Question 61

Which pair(s) of molecules below are neither isomers nor conformers?

A) Pair 1
B) Pair 2
C) Pair 3
D) Pair 4
E) These are all either isomers or conformers.

Question 62

Which pair(s) of molecules below are conformers?

A) Pairs 1, 3, and 4
B) Pairs 2 and 4
C) Pairs 2 and 3
D) Pair 2 only
E) Pair 4 only

Question 63

Which of the following pairs of molecules are geometric isomers?

A)
B)
C)
D)
E)

Question 64

What is the parent chain name of the hydrocarbon below?

A) butene
B) hexane
C) hexene
D) heptane
E) heptene

Question 65

Identify the three parts of the following IUPAC name.

A) prefix: 3-ethyl root: hexene suffix: none
B) prefix: 3-ethyl root: hex suffix: -ene
C) prefix: hex root: ene suffix: none
D) prefix: 3 root: ethyl suffix: hexene
E) prefix: eth root: yl suffix: hexene

Question 66

Which pair(s) of molecules below are geometric isomers?

A) All of them
B) Pairs 2, 3, and 4
C) Pairs 1, 2, and 3
D) Pair 1, 3, and 4
E) Pair 4 only

Question 67

Which of the following condensed structures are branched and which are straight chains?

A)a
B)b
C)c
D)d
E)e

Question 68

Which of the following hydrocarbons are branched and which are straight chains?

A) All of these hydrocarbons are branched.
B) All of these hydrocarbons are branched except II.
C) All of these hydrocarbons are straight chains except III.
D) I and III are branched, and II and IV are straight chains.
E) II, III, and IV are straight chains and I is branched.

Question 69

When naming in the IUPAC system, the main chain has which of the following characteristics? I. It is the part of the structure that is written horizontally.
II) It is the longest continuous chain.
III) It contains any double or triple bonds in the structure.

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

Question 70

Arachidonic acid is a fat found in many foods such as meat, dairy products, and eggs. What type of carbon-carbon double bonds does arachidonic acid contain?

A) Arachidonic acid contains all trans double bonds.
B) Arachidonic acid contains all cis double bonds.
C) Arachidonic acid contains two cis and two trans double bonds.
D) Arachidonic acid contains one cis and three trans double bonds.
E) Arachidonic acid contains three cis and one trans double bonds.

Question 71

Ethynyl estradiol, a synthetic hormone, is a common component of birth control pills. Which bond in ethynyl estradiol is an alkyne?

A) A
B) B
C) C
D) D
E) A and C

Question 72

In which of the following choices are the alkenes correctly labeled?

A)
B)
C)
D)
E)

Question 73

For naming purposes, which carbon is the double bond located in this branched-chain hydrocarbon?

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

Question 74

A molecule has the following IUPAC name: 1-hexyne. What does this name mean?

A) The molecule is an unbranched six-carbon alkane.
B) The molecule is a branched six-carbon alkane.
C) The molecule is an unbranched six-carbon alkene.
D) The molecule is a branched six-carbon alkyne.
E) The molecule is an unbranched six-carbon alkyne.

Question 75

Converting a cis isomer to a trans isomer

A) requires nothing. Cis and trans isomers are actually just conformers, so they interconvert all of the time.
B) requires a chemical reaction.
C) requires a physical change such as melting or boiling.
D) requires both a chemical reaction and a physical change.
E) is impossible. There is no way to convert a cis isomer to a trans isomer.

Question 76

Which skeletal line structure best represents 2-butyne?

A)
B)
C)
D)
E)

Question 77

Which of the following structures is the condensed structural formula of 1-hexene?

A)
B)
C)
D)
E)

Question 78

What are the locator number(s) and substituent name(s) for this branched-chain hydrocarbon?

A) 3-methyl
B) 2-ethyl
C) 1-ethyl-1-methyl
D) 5-ethyl
E) 5-methyl

Question 79

What is the name of the following hydrocarbon?

A) trans-3-pentane
B) trans-3-pentene
C) cis-3-pentane
D) trans-2-pentene
E) cis-2-pentene

Question 80

Which of the following pairs of compounds are geometric isomers?

A)
B)
C)
D)
E)