Chapter 10 Alkenes Test Questions & Answers

Organic Chemistry, 6e (Smith)

Chapter 10 Alkenes

1) Which of the following alkenes are terminal alkenes? 

A) I and II

B) II and III

C) I and IV

D) I and III

2) Which of the following alkenes are internal alkenes?

A) I and II

B) II and III

C) I and III

D) II and IV

3) Which of the statements about the properties of the carbon-carbon double bond is not true?

A) There is restricted rotation around the carbon-carbon double bond.

B) Whenever the two groups on each end of a carbon-carbon double bond are the same, two diastereomers are possible.

C) Trans alkenes are generally more stable than cis alkenes.

D) The stability of the carbon-carbon double bond increases as the number of substituent groups increases.

4) Calculate the degree of unsaturation for a molecule with molecular formula C6H11Cl.

A) 1

B) 2

C) 3

D) 0

5) Calculate the degree of unsaturation for a molecule with molecular formula C8H9N.

A) 2

B) 3

C) 4

D) 5

6) What is the IUPAC name for the following compound? 

A) 6-Ethyl-1-heptene

B) 2-Ethyl-1-heptene

C) 2-Ethyl-1-octene

D) 6-Ethyl-6-heptene

7) What is the IUPAC name for the following compound? 

A) 1-Methylcyclopentene

B) 2-Methyl-1-cyclopentene

C) 1-Methylene-1-methylcyclopentane

D) 1-Methylcyclohexene

8) What is the IUPAC name for the following compound? 

A) 1,2-Dimethylcyclohexene

B) 2,3-Dimethylcyclohexene

C) 1,6-Dimethylcyclohexene

D) 1,2-Dimethyl-3-cyclohexene

9) What is the IUPAC name for the following compound?

A) 5-Methyl-5-hexen-2-ol

B) 6-Methyl-6-hepten-2-ol

C) 6-Hydroxy-2-methylheptene

D) 6-Hydroxy-2-methyl-1-heptene

10) What is the IUPAC name for the following compound? 

A) 4-Ethyl-3-methyl-1-octen-5-ol

B) 3-Ethyl-4-methyl-2-octen-5-ol

C) 5-Ethyl-6-methyl-7-octen-4-ol

D) 4-Ethyl-6-methyl-1-octen-5-ol

11) Label each C-C double bond in Kavain, a naturally occurring relaxant, as E or Z. 

A) I = Z and II = Z

B) I = Z and II = E

C) I = E and II = E

D) I = E and II = Z

12) What is the common name of the following compound? 

A) 2-Vinylcyclohexene

B) 2-Allylcyclohexene

C) 1-Allylcyclohexene

D) 1-Vinylcyclohexene

13) Rank the following isomers in order of increasing boiling point, putting the least first. 

A) I < II < III

B) I < III < II

C) II < III < I

D) II < I < III

14) Which of the following compounds has the highest boiling point? 

A) I

B) II

C) III

D) IV

15) Which of the following is a terpene? 

A) I

B) II

C) III

D) IV

16) What is the major product of the following reaction? 

A) I

B) II

C) III

D) IV

17) Which of the following statements about alkenes is not true?

A) They are less reactive than alkanes.

B) They can exist as cis/trans isomers.

C) The bond angle around the C-C double bond is approximately 120°.

D) The carbon of the C-C double bond is sp2 hybridized.

18) Which of the following statements about alkenes is true?

A) Alkenes react with nucleophiles and bases.

B) Alkenes contain double bonds from two sp-hybridized carbon atoms.

C) In the reactions of alkenes, the  bond is not always broken.

D) Alkenes react with electrophiles.

19) Rank the following compounds in order of decreasing stability, putting the most stable first. 

A) I > II > III

B) II > I > III

C) III > II > I

D) III > I > II

20) Which of the following reaction conditions would result in anti-Markovnikov addition to an alkene?

A) H2O/H3O+

B) HBr

C) HCl

D) [1] BH3; [2] H2O2/HO-

21) Which of the following alkenes will undergo a carbocation rearrangement when reacting with H2O in the presence of a small amount of H2SO4? 

A) Only I and II

B) Only I and III

C) Only II and III

D) I, II, and III

22) In which of the following alkene addition reactions will carbocation rearrangements occur?

A) Addition of Br2 and H2O

B) Addition of Br2

C) Addition of Cl2 and H2O

D) Addition of H2O in the presence of H2SO4

23) Markovnikov addition of HBr to CH3CH=CH2 involves which of the following?

A) Initial attack by bromide anion (Br-).

B) Initial attack by bromine radical (Br•).

C) Formation of a primary carbocation.

D) Formation of a secondary carbocation.

24) Rearrangements can occur in which of the following reactions?

A) Addition of Cl2 to an alkene.

B) Addition of HOBr to an alkene.

C) Addition of H2O/H3O+ to an alkene.

D) None of these.

25) Which of the following alkenes reacts fastest with HCl? 

A) I

B) II

C) III

D) IV

26) Predict the major product of the following reaction. 

A) I

B) II

C) III

D) IV

27) Predict the product(s) of the following reaction. 

A) Only I and II

B) Only I and III

C) Only II and III

D) Only III and IV

28) Predict the product of the following reaction.

A) I

B) II

C) III

D) IV

29) Predict the major product of the following reaction. 

A) I

B) II

C) III

D) IV

30) Predict the major product of the following reaction.

A) I

B) II

C) III

D) IV

31) Predict the major product(s) of the following reaction. 

A) Only I and II

B) Only II and III

C) Only III and IV

D) Only I and IV

32) Predict the major product(s) of the following reaction. 

A) Only I and II

B) Only II and IV

C) Only II and III

D) Only I and IV

33) What is the major product obtained from the following reaction? 

A) I

B) II

C) III

D) IV

34) What is the major product obtained from the following reaction (assume enantiomer is also formed)? 

A) I

B) II

C) III

D) IV

35) What is (are) the major product(s) obtained from the following reaction? 

A) Only I

B) Only II

C) Only III

D) Only I and II

36) What is (are) the major product(s) obtained from the following reaction?

A) Only I

B) Only II

C) Only III

D) Only I and II

37) What is the best choice of reagent to accomplish the following transformation? 

A) HBr

B) Br2, H2O

C) Br2

D) H2O2/Br2

38) What is the best choice of reagent to accomplish the following transformation? 

A) H2O, Br2

B) [1] BH3; [2] H2O2/HO-

C) H2O, H2SO4

D) [1] BH3; [2] H2O

39) What type of reactive intermediate is formed in the reaction of an alkene with HI to give an iodoalkane?

A) Carbanion

B) Carbocation

C) Cyclic bromonium ion

D) Radical

40) What type of reactive intermediate is formed in the reaction of an alkene with Br2 and H2O to give a bromohydrin?

A) Carbanion

B) Radical

C) Carbocation

D) Cyclic bromonium ion

41) Rank the carbocation in order of increasing stability, putting the least stable first. 

A) III < I < II

B) III < II < I

C) I < II < III

D) I < III < II

42) Which of the following statements about the stereochemistry of electrophilic addition of HX to alkenes is true?

A) Achiral starting materials yield an unequal mixture of two enantiomers.

B) Hydrohalogenation occurs with syn stereochemistry only.

C) Hydrohalogenation occurs with anti stereochemistry only.

D) Hydrohalogenation occurs with syn and anti addition of HX.

43) Which of the following reactions of alkenes takes place with anti stereochemistry only?

A) Addition of HBr

B) Addition of H2O in the presence of H2SO4

C) Addition of BH3 followed by H2O2/HO-

D) Addition of Br2

44) Predict the product of the following reaction, ignoring stereochemistry. 

A) I

B) II

C) III

D) IV

45) What is the starting material in the following reaction? 

A) I

B) II

C) III

D) IV

46) What is (are) the missing reagent(s) in the following reaction? 

A) Br2/CCl4

B) NBS, DMSO/H2O

C) [1] Br2; [2] H2O

D) [1] BH3; [2] H2O2/HO-

47) Which of the following statements about hydroboration/oxidation of alkenes is true?

A) In hydroboration, the boron atom bonds to the more substituted carbon.

B) Hydroboration occurs with anti addition.

C) Oxidation occurs with retention of configuration.

D) 9-BBN does not undergo hydroboration in the same manner as BH3.

48) Which of the following alkenes is an E alkene?

A) I

B) II

C) III

D) IV

49) Which alkene reacts fastest with HBr? 

A) I

B) II

C) III

D) IV

50) Calculate the degree of unsaturation for the following molecule:

A) 2

B) 3

C) 4

D) 5

51) Calculate the degree of unsaturation for the following molecule:

A) 2

B) 3

C) 4

D) 5

52) What is the IUPAC name of the following compound?

A) (E,R)-4-bromo-4-hexen-2-ol

B) (Z,R)-4-bromo-4-hexen-2-ol

C) (E,S)-4-bromo-4-hexen-2-ol

D) (Z,S)-4-bromo-4-hexen-2-ol

53) What is the IUPAC name of the following compound?

A) R-4,4-dibromo-2-cyclohexen-1-ol

B) S-4,4-dibromo-2-cyclohexen-1-ol

C) R-4,4-dibromo-5-cyclohexen-1-ol

D) S-4,4-dibromo-5-cyclohexen-1-ol

54) What is the major product of the following reaction?

A) I

B) II

C) III

D) IV