Question 1

Which of the following best describes the mechanism for the addition of HX to an alkene?

Accepted Answer

A two-step process involving carbocation formation followed by nucleophilic attack.

Question 2

During the hydration of an alkene, which intermediate is formed?

Accepted Answer

A carbocation

Question 3

Which reagent is commonly used for the anti-Markovnikov addition of HBr to alkenes?

Accepted Answer

Hydrogen peroxide ($$\mathrm{H_2O_2})$$

Question 4

What is the major product when 2-butene reacts with $$\mathrm{Br_2$} in$$ $$\mathrm{$$CCl_4$$}$$?

Accepted Answer

1,2-dibromobutane

Question 5

Which of the following reactions is used to convert an alkyne to a cis-alkene?

Accepted Answer

Hydrogenation with Lindlar's catalyst

Question 6

In the hydroboration-oxidation of alkenes, what is the regiochemistry of the alcohol product?

Accepted Answer

Anti-Markovnikov

Question 7

Which of the following best describes the product of ozonolysis of 1-hexene followed by reductive workup?

Accepted Answer

Butanal and ethanal

Question 8

What is the expected product when ethyne reacts with excess $$\mathrm{Br_2$}$$?

Accepted Answer

1,1,2,2-tetrabromoethane

Question 9

Which reaction mechanism is involved in the formation of halohydrins from alkenes?

Accepted Answer

Electrophilic addition followed by nucleophilic attack by water

Question 10

Which of the following is a key step in the acid-catalyzed hydration of alkynes?

Accepted Answer

Formation of an enol intermediate

Question 11

What is the major product when 1-butene undergoes hydroboration-oxidation?

Accepted Answer

1-butanol

Question 12

Which of the following reactions is used to synthesize vicinal diols from alkenes?

Accepted Answer

Oxidation with $$\mathrm{$$OsO_4$$}$$

Question 13

Which mechanism is responsible for the anti addition of $$\mathrm{Br_2$} to $$alkenes?

Accepted Answer

Formation of a bromonium ion intermediate

Question 14

What is the product of the reaction between 2-methyl-2-butene and $$\mathrm{H_2SO_4}/$$water?

Accepted Answer

2-methyl-2-butanol

Question 15

Which of the following is a result of the oxidative cleavage of alkenes using $$\mathrm{$$KMnO_4$$}$$ under acidic conditions?

Accepted Answer

Formation of carboxylic acids and/or ketones

Question 16

Which reaction is used to convert an alkene to an epoxide?

Accepted Answer

Reaction with a peracid such as $$\mathrm{mCPBA}$$

Question 17

What is the expected product when 1-butyne is treated with $$\mathrm{$$HgSO_4$$}$$ and $$\mathrm{H_2SO_4}$$?

Accepted Answer

2-butanone

Question 18

Which of the following best describes the stereochemistry of the dihydroxylation of alkenes using $$\mathrm{$$OsO_4$$}$$?

Accepted Answer

Syn addition of two hydroxyl groups

Question 19

Which reaction mechanism is involved in the formation of alkyl halides from alcohols using $$\mathrm{$$SOCl_2$$}$$?

Accepted Answer

Nucleophilic substitution (SN2 or SN1)

Question 20

What is the major product when ethylene reacts with $$\mathrm{$$KMnO_4$$}$$ under cold, dilute conditions?

Accepted Answer

Ethylene glycol

Organic Chemistry Mechanisms: Key Topics for Final Exam (Chapters 13, 14, 18)

Study Guide - Practice Questions