Question 1

Which of the following carboxylic acid derivatives is the most reactive toward nucleophilic acyl substitution?

Accepted Answer

Acyl chloride ($$RCOCl)$$

Question 2

Why are amides less reactive than esters in nucleophilic acyl substitution reactions?

Accepted Answer

Nitrogen in amides is less electronegative and stabilizes the positive charge via resonance.

Question 3

Which of the following best explains why acyl chlorides are highly reactive in nucleophilic acyl substitution?

Accepted Answer

Poor overlap between the carbon 2p and chlorine 3p orbitals reduces resonance stabilization.

Question 4

Which strategy would favor the formation of an ester in a Fischer esterification reaction?

Accepted Answer

Adding excess alcohol

Question 5

In the saponification of a triglyceride, what are the main products?

Accepted Answer

Soap and glycerol

Question 6

Which of the following statements about nucleophilic acyl substitution is correct?

Accepted Answer

A more reactive derivative can be converted into a less reactive one.

Question 7

Which of the following is the best leaving group in nucleophilic acyl substitution reactions?

Accepted Answer

$$Cl^-$$

Question 8

A chemist wants to hydrolyze an ester to a carboxylic acid. Which condition will favor the formation of the carboxylic acid?

Accepted Answer

Excess water

Question 9

Which of the following is a correct resonance structure for an amide?

Accepted Answer

$$RCONH_2$$ \leftrightarrow R-C(=O)-$$NH_2$$ \leftrightarrow R-C(-O^-)=$$NH_2$$^+$$

Question 10

Which of the following is NOT a Class I carbonyl compound?

Accepted Answer

Ketone ($$RCOR')$$

Question 11

Which of the following best describes the role of resonance in the stability of amides?

Accepted Answer

Resonance delocalizes the lone pair on nitrogen, increasing stability and decreasing reactivity.

Question 12

Which of the following is the correct order of reactivity for carboxylic acid derivatives (most to least reactive)?

Accepted Answer

Acyl chloride \u003e Anhydride \u003e Ester \u003e Amide

Question 13

Which of the following is a common method for synthesizing a primary amine from a nitrile?

Accepted Answer

Reduction with $$LiAlH_4$$

Question 14

Which of the following statements about the hydrolysis of carboxylic acid derivatives is correct?

Accepted Answer

Hydrolysis of any carboxylic acid derivative forms a carboxylic acid.

Question 15

Which of the following best explains why halides are poor bases and poor at resonance stabilization in acyl chlorides?

Accepted Answer

Halides are highly electronegative and large, leading to poor orbital overlap.

Question 16

Which of the following is a correct application of Le Châtelier’s principle in ester hydrolysis?

Accepted Answer

Adding excess water to favor carboxylic acid formation

Question 17

Which of the following is a product of acid-catalyzed hydrolysis of an amide?

Accepted Answer

Carboxylic acid

Question 18

Which of the following best describes the mechanism of nucleophilic acyl substitution?

Accepted Answer

Nucleophile attacks the carbonyl carbon, forming a tetrahedral intermediate, followed by loss of the leaving group.

Question 19

Which of the following is a correct statement about the conversion of carboxylic acid derivatives?

Accepted Answer

An acyl chloride can be converted into an amide by reaction with $$NH_3.$$

Reactions of Carboxylic Acids and Their Derivatives: Structure, Reactivity, and Mechanisms

Study Guide - Practice Questions