Question 1

Which statement best explains why trans alkenes are generally more stable than cis alkenes?

Accepted Answer

Trans alkenes have less steric hindrance between substituents.

Question 2

According to Zaitsev’s Rule, which product will be favored in the E2 elimination of 2-bromo-2-methylbutane using sodium ethoxide?

Accepted Answer

The more highly substituted alkene.

Question 3

Which base would most likely favor the formation of the Hofmann product in an E2 elimination reaction?

Accepted Answer

Potassium tert-butoxide

Question 4

What is the correct (E)/(Z) designation for the following alkene: $$CH_3CH=$$CHCH_3$$?

Accepted Answer

E (trans)

Question 5

Which of the following statements about the E2 mechanism is FALSE?

Accepted Answer

E2 reactions proceed via a carbocation intermediate.

Question 6

Which of the following would increase the rate of an SN2 reaction between 1-chloro-5-methylhexane and CN$$^-$$ ion, assuming all other conditions are constant?

Accepted Answer

Doubling the concentration of both reactants increases the rate four times.

Question 7

Which of the following is the major product when 2-bromo-2-methylbutane undergoes E2 elimination with a small base?

Accepted Answer

$$CH_3C(CH_3$)=$$CHCH_3$$

Question 8

Which step is rate-determining in acid-catalyzed alcohol dehydration (E1 mechanism)?

Accepted Answer

Formation of a carbocation from the protonated alcohol.

Question 9

Which of the following statements about the stability of alkenes is correct?

Accepted Answer

The greater the number of alkyl groups attached to the double bond, the greater the stability.

Question 10

Which of the following is a consequence of using a bulky base in an E2 elimination?

Accepted Answer

The least substituted alkene (Hofmann product) is favored.

Question 11

Which of the following best describes the stereochemical requirement for an E2 elimination on a cyclohexane ring?

Accepted Answer

The leaving group and the hydrogen must both be axial.

Question 12

Which of the following is true regarding the heat of hydrogenation of alkenes?

Accepted Answer

A lower heat of hydrogenation indicates a more stable alkene.

Question 13

Which of the following is NOT a factor that favors E2 elimination over E1?

Accepted Answer

Use of a polar protic solvent.

Question 14

Which of the following is the correct product for the E2 elimination of 2-bromo-2-methylbutane with potassium tert-butoxide?

Accepted Answer

$$CH_2=C$$($$CH_3)_2$

Question 15

Which of the following statements about the (E)/(Z) system for alkene stereochemistry is correct?

Accepted Answer

The (Z) isomer has the highest priority groups on the same side of the double bond.

Question 16

Which of the following is a real-world application of alkene hydrogenation?

Accepted Answer

Industrial production of margarine from vegetable oils.

Question 17

Which of the following is the major product when 2-methyl-2-butanol undergoes acid-catalyzed dehydration?

Accepted Answer

$$CH_3C(CH_3$)=$$CHCH_3$$

Question 18

Which of the following statements about carbocation rearrangements during alcohol dehydration is correct?

Accepted Answer

A methyl or hydride shift can occur to form a more stable carbocation.

Alkenes and Alkynes I: Properties, Synthesis, and Elimination Reactions of Alkyl Halides

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