Question 1

Which of the following statements best explains why ethers have lower boiling points than alcohols of comparable molecular weight?

Accepted Answer

Ethers cannot form hydrogen bonds with each other because they lack an O-H group.

Question 2

Arrange the following compounds in order of increasing solubility in water: hexane, diethyl ether, ethylene glycol dimethyl ether.

Accepted Answer

Hexane \u003c Diethyl ether \u003c Ethylene glycol dimethyl ether

Question 3

Which of the following is the best combination of reactants for the Williamson ether synthesis of 2-methoxypropane?

Accepted Answer

$$\mathrm{CH_3CH(O^-)CH_3$}$$ + $$\mathrm{CH_3I}$$

Question 4

Why does the Williamson ether synthesis fail when using a tertiary alkyl halide such as 2-bromo-2-methylpropane?

Accepted Answer

The reaction proceeds via E2 elimination, forming an alkene instead of an ether.

Question 5

Which of the following best describes the product of acid-catalyzed dehydration of ethanol at 140°C?

Accepted Answer

$$\mathrm{CH_3CH_2OCH_2CH_3} ($$diethyl ether)

Question 6

Which of the following is the correct IUPAC name for the compound shown below?

$$\mathrm{CH_3CH_2SCH_2CH_3}$$

Accepted Answer

Ethylsulfanylethane

Question 7

What is the major product when cyclohexene reacts with peroxyacetic acid ($$\mathrm{CH_3CO_3H}) in$$ $$\mathrm{CH_2Cl_2}$$?

Accepted Answer

1,2-Epoxycyclohexane (Cyclohexene oxide)

Question 8

Which of the following statements about the acid-catalyzed ring opening of epoxides is correct?

Accepted Answer

The nucleophile attacks the more substituted carbon due to partial carbocation character.

Question 9

Which reagent would convert methyl phenyl sulfide to methyl phenyl sulfoxide?

Accepted Answer

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

Question 10

Which of the following best describes the mechanism for the conversion of a halohydrin to an epoxide using base?

Accepted Answer

An internal $$\mathrm{S_N2}$$ reaction where the alkoxide displaces the halide.

Question 11

Which of the following is a correct statement about the stereochemistry of epoxidation of alkenes with peroxycarboxylic acids?

Accepted Answer

The stereochemistry of the alkene is retained in the epoxide product.

Question 12

Which of the following best explains why ethylene glycol dimethyl ether is more soluble in water than diethyl ether?

Accepted Answer

It has more oxygen atoms, providing more sites for hydrogen bonding with water.

Question 13

Which of the following is the correct product for the acid-catalyzed hydrolysis of oxirane (ethylene oxide)?

Accepted Answer

$$\mathrm{HOCH_2CH_2OH} ($$ethylene glycol)

Question 14

Which of the following is the correct IUPAC name for the compound $$\mathrm{CH_3CH_2SSCH_2CH_2CH_3}$$?

Accepted Answer

Ethylsulfanylpropane (or Ethyl propyl sulfide)

Question 15

Which of the following best describes the product of the reaction of 1,4-dichlorobutane with sodium sulfide ($$\mathrm{Na_2S}$$)?

Accepted Answer

Thiophene (a five-membered cyclic sulfide)

Question 16

Which of the following is the correct product when dimethyl sulfide is oxidized with oxygen in the presence of oxides of nitrogen?

Accepted Answer

Dimethyl sulfoxide ($$\mathrm{(CH_3$)_2SO})$$

Question 17

Which of the following best describes the product of acid-catalyzed ring opening of 1,2-epoxycyclopentane with water?

Accepted Answer

trans-1,2-Cyclopentanediol (a racemic mixture)

Question 18

Which of the following is a correct statement about the oxidation of sulfides?

Accepted Answer

Treatment with one equivalent of $$\mathrm{H_2O_2}$$ gives a sulfoxide.

Ethers, Epoxides, and Sulfides: Structure, Properties, Synthesis, and Reactions

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