Question 1

Which of the following statements best describes the dehydration of secondary and tertiary alcohols?

Accepted Answer

It proceeds via an $$E_1$$ mechanism involving carbocation formation and possible rearrangement.

Question 2

During the acid-catalyzed dehydration of 3,3-dimethylbutan-2-ol, which major product is formed according to Zaitsev’s rule?

Accepted Answer

2,3-dimethyl-2-butene (tetrasubstituted alkene)

Question 3

What is the driving force for the 1,2-methyl shift during the dehydration of certain alcohols?

Accepted Answer

Formation of a more substituted and stable carbocation

Question 4

Which mechanism is followed during the dehydration of primary alcohols?

Accepted Answer

E2 mechanism

Question 5

Why does the dehydration of 4-methylhexan-3-ol not undergo a 1,2-methyl shift?

Accepted Answer

Because the methyl shift would still result in a secondary carbocation

Question 6

Which of the following is true regarding Zaitsev’s rule in alcohol dehydration?

Accepted Answer

The major product is the most substituted alkene.

Question 7

In the reaction of alcohols with hydrogen halides, which mechanism is followed by tertiary alcohols?

Accepted Answer

SN1 mechanism

Question 8

Which step is rate-determining in the $$E_1$$ dehydration of a secondary alcohol?

Accepted Answer

Loss of water to form the carbocation

Question 9

What is the role of sulfuric acid in Fischer esterification?

Accepted Answer

It acts as a catalyst to protonate the carbonyl group.

Question 10

Which of the following esters is formed by the reaction of glycerine with concentrated nitric acid?

Accepted Answer

Nitroglycerine (nitrate ester)

Question 11

Which of the following statements about the $$S_N2$$ reaction of primary alcohols with hydrogen halides is correct?

Accepted Answer

The reaction is concerted and involves a backside attack.

Question 12

Which inorganic ester is important in the structure of DNA and RNA?

Accepted Answer

Phosphate ester

Question 13

A patient is exposed to nitroglycerine. Which type of ester is this compound?

Accepted Answer

Nitrate ester

Question 14

Which of the following is a correct description of the $$E_2$$ mechanism in the dehydration of primary alcohols?

Accepted Answer

It is a concerted process where the base removes a proton as the leaving group departs.

Question 15

Which rearrangement is most likely to occur during the $$E_1$$ dehydration of 4-methylhexan-3-ol?

Accepted Answer

1,2-hydride shift

Question 16

Which of the following is NOT a product of the acid-catalyzed dehydration of 3,3-dimethylbutan-2-ol?

Accepted Answer

2-methyl-2-butene

Question 17

Which of the following is a correct statement about the formation of alkyl halides from alcohols?

Accepted Answer

Secondary and tertiary alcohols react with hydrogen halides via an $$S_N1$$ mechanism.

Question 18

Which of the following is the correct equation for Fischer esterification?

Accepted Answer

$$ \mathrm{RCOOH} + \mathrm{R'OH} \xrightarrow{H_2SO_4} \mathrm{RCOOR'} + H_2O $$

Question 19

Which of the following is a correct statement about tosylate esters?

Accepted Answer

They are formed by the reaction of alcohols with p-toluenesulfonic acid.

Reactions of Alcohols: Dehydration, Substitution, and Ester Formation

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