01
Choose one
1 point
What is the principal acyl product when ammonia reacts with acetic anhydride?
Free Practice Quiz Question List
07 Carboxylic Acid Derivatives and Acyl Substitution Online Quiz Questions
Use this free practice quiz with 20 questions to review 07 Carboxylic Acid Derivatives and Acyl Substitution, test your knowledge, and prepare for your next test or exam.
20 questions
02
Written response
1 point
What is the name of the intermediate formed when a nucleophile attacks the acyl carbon and the carbonyl π electrons move onto oxygen?
03
Fill in the blank
1 point
In nucleophilic acyl substitution, the group attached to the acyl carbon that departs as the tetrahedral intermediate collapses is the .
04
True or false
1 point
True or false: Steric crowding near an acyl carbon can slow nucleophilic attack.
- A
True
- B
False
05
True or false
1 point
True or false: Under acidic conditions, protonation can make a carbonyl more electrophilic and can improve leaving-group ability.
- A
True
- B
False
06
Choose one
1 point
Why do carboxylic acids require special consideration when predicting nucleophilic acyl substitution?
- A
Their hydroxyl group is an especially good leaving group.
- B
Their hydroxyl group is a poor leaving group, and acid–base reactions often occur first.
- C
They cannot undergo any reactions at the acyl carbon.
- D
Their carbonyl has no electrophilic character.
07
Written response
1 point
In base-promoted ester hydrolysis, what type of acyl product forms, rather than a neutral carboxylic acid?
08
Choose one
1 point
Which is generally more reactive toward nucleophilic acyl substitution: a thioester or an ester, and why?
- A
The thioester, because sulfur donates less effectively to the carbonyl than ester oxygen.
- B
The ester, because oxygen donates less effectively to the carbonyl than sulfur.
- C
The ester, because oxygen is a better leaving group than sulfur in this comparison.
- D
They have identical reactivity because both contain a carbonyl.
09
Choose all
1 point
Select all statements that describe the common addition–elimination pathway for nucleophilic acyl substitution.
- A
The nucleophile attacks the acyl carbon.
- B
The carbonyl π electrons move onto oxygen during the initial attack.
- C
The tetrahedral intermediate collapses as the carbonyl reforms and a leaving group departs.
- D
A proton transfer must always occur before the nucleophile attacks.
10
Choose all
1 point
Select all reasons that help explain why amides are relatively unreactive in nucleophilic acyl substitution.
- A
Nitrogen donates electron density strongly to the carbonyl by resonance.
- B
An amide-derived nitrogen anion is an unfavorable leaving group.
- C
Nitrogen donates less strongly than sulfur, making the carbonyl unusually electrophilic.
- D
Amide nitrogen is a better leaving group than chloride.
11
Fill in the blank
1 point
The common nucleophilic acyl substitution pathway proceeds first by to form a tetrahedral intermediate, then by as the carbonyl reforms and a leaving group departs.
12
Choose one
1 point
Benzoyl chloride reacts with 2-propanol under conditions that neutralize the HCl formed. What is the organic product?
- A
Benzoic acid
- B
Benzamide
- C
Isopropyl benzoate
- D
Isopropyl benzyl ether
13
True or false
1 point
True or false: Carboxylate ions are especially unreactive acyl compounds.
- A
True
- B
False
14
Choose one
1 point
Which proposed conversion is most consistent with the general reactivity trend and the usual direction of acyl substitution?
- A
Acid chloride to ester, because the starting derivative is more reactive.
- B
Ester to acid chloride by direct substitution, because the ester is more reactive.
- C
Amide to acid chloride by direct substitution, because nitrogen is an excellent leaving group.
- D
Carboxylate to ester by reversing base-promoted hydrolysis under the same conditions.
15
Open ended
1 point
A chemist proposes converting an amide into an ester simply by adding an alcohol. Explain why this direct substitution is not ordinarily feasible and state what broad strategy the conversion requires.
16
Choose one
1 point
How does steric crowding near an acyl carbon generally affect nucleophilic acyl substitution?
- A
It makes the leaving group more basic.
- B
It hinders nucleophilic attack at the acyl carbon.
- C
It prevents the carbonyl oxygen from carrying partial charge.
- D
It makes proton transfer impossible.
17
Choose one
1 point
Why are thioesters generally more reactive toward nucleophilic acyl substitution than esters?
- A
Sulfur donates electron density more strongly than oxygen.
- B
Thioesters have no leaving group.
- C
Sulfur donates electron density to the carbonyl less effectively than oxygen.
- D
Esters cannot form tetrahedral intermediates.
18
Choose one
1 point
What is one way acidic conditions can promote nucleophilic acyl substitution?
- A
Protonation always prevents nucleophilic attack.
- B
Protonation can make the carbonyl more electrophilic and improve leaving-group ability.
- C
Acidic conditions eliminate the need for a leaving group.
- D
Protonation converts every acyl derivative into an acid chloride.
19
Written response
1 point
What intermediate forms when a nucleophile attacks an acyl carbon and the carbonyl π electrons move onto oxygen?
20
Written response
1 point
What amide is formed when ammonia reacts with acetic anhydride?