,Verified CHEM 219 Module 6 Exam Principles of
Organic Chemistry w/Lab | Portage (2026–2027)
Actual(PDF)
1. What is the correct IUPAC name for the compound CH₃-CH₂-CH₂-NH₂?
A) Propan-1-amine
B) Propan-2-amine
C) Propylamine
D) 1-aminopropane
Correct Answer: Propan-1-amine
Rationale: The compound is a primary amine with a three-carbon chain. The parent chain is propane,
and the amine functional group takes the suffix "-amine". Numbering from the end closest to the
nitrogen gives the amino group at carbon 1. The correct IUPAC name is propan-1-amine.
"Propylamine" is a common name, and "1-aminopropane" is an acceptable but less preferred
alternative.
2. Which of the following correctly ranks the following amines in order of increasing boiling point:
trimethylamine, methylamine, dimethylamine?
A) Trimethylamine < dimethylamine < methylamine
B) Methylamine < dimethylamine < trimethylamine
C) Trimethylamine < methylamine < dimethylamine
D) Dimethylamine < methylamine < trimethylamine
Correct Answer: Trimethylamine < methylamine < dimethylamine
Rationale: Boiling point in amines is influenced by molecular weight and hydrogen bonding. Primary
amines have the strongest hydrogen bonds (two N-H bonds), secondary amines have one N-H bond,
and tertiary amines have no N-H bonds (only weaker dipole-dipole and London forces). However,
branching also matters. The order of increasing boiling point is trimethylamine (lowest, no H-bonding)
< methylamine (primary) < dimethylamine (secondary, higher molecular weight than methylamine).
,3. Which of the following is the major product of the reaction of benzene with bromine in the
presence of FeBr₃?
A) Bromobenzene
B) Benzene (no reaction)
C) 1,2-dibromobenzene
D) 1,3-dibromobenzene
Correct Answer: Bromobenzene
Rationale: Benzene undergoes electrophilic aromatic substitution (EAS) with bromine in the presence
of a Lewis acid catalyst (FeBr₃) to form bromobenzene. The reaction introduces a single bromine atom
onto the ring. Further bromination is possible but requires more vigorous conditions, so the major
product of the monosubstitution is bromobenzene.
4. Which of the following is the correct structure for N,N-dimethylpropan-1-amine?
A) CH₃-CH₂-CH₂-N(CH₃)₂
B) CH₃-CH₂-CH₂-NH-CH₃
C) CH₃-CH₂-CH₂-NH₂
D) (CH₃)₂CH-NH-CH₃
Correct Answer: CH₃-CH₂-CH₂-N(CH₃)₂
Rationale: The parent chain is propan-1-amine (a three-carbon chain with the amino group at C1). The
"N,N-dimethyl" prefix indicates that two methyl groups are attached to the nitrogen atom. Therefore,
the structure is CH₃-CH₂-CH₂-N(CH₃)₂. The other options represent different amines: CH₃-CH₂-CH₂-NH-
CH₃ is N-methylpropan-1-amine, CH₃-CH₂-CH₂-NH₂ is propan-1-amine, and (CH₃)₂CH-NH-CH₃ is N-
methylpropan-2-amine.
5. In the nitration of benzene, what is the electrophile that attacks the aromatic ring?
A) NO₂⁺ (nitronium ion)
B) NO₂⁻ (nitrite ion)
, C) HNO₃ (nitric acid)
D) NO (nitric oxide)
Correct Answer: NO₂⁺ (nitronium ion)
Rationale: In the nitration of benzene, concentrated nitric acid (HNO₃) is protonated by sulfuric acid
(H₂SO₄), leading to the formation of the nitronium ion (NO₂⁺). This highly electrophilic species is the
active electrophile that attacks the aromatic ring. The nitronium ion is a strong electrophile due to the
positive charge on nitrogen.
6. Which of the following amines is the most basic in aqueous solution?
A) Ammonia
B) Methylamine
C) Dimethylamine
D) Trimethylamine
Correct Answer: Dimethylamine
Rationale: In aqueous solution, the basicity of amines is influenced by both the electron-donating
effect of alkyl groups and solvation of the ammonium ion. For aliphatic amines in water, the order of
basicity is generally secondary > primary > tertiary > ammonia. Dimethylamine (secondary) is the most
basic due to a balance of inductive effects and solvation. Trimethylamine is less basic than
dimethylamine due to steric hindrance to solvation.
7. What is the product of the reaction of aniline (C₆H₅NH₂) with nitrous acid (HNO₂) at 0-5°C?
A) Benzenediazonium chloride
B) Nitrobenzene
C) Phenol
D) Chlorobenzene
Correct Answer: Benzenediazonium chloride
Organic Chemistry w/Lab | Portage (2026–2027)
Actual(PDF)
1. What is the correct IUPAC name for the compound CH₃-CH₂-CH₂-NH₂?
A) Propan-1-amine
B) Propan-2-amine
C) Propylamine
D) 1-aminopropane
Correct Answer: Propan-1-amine
Rationale: The compound is a primary amine with a three-carbon chain. The parent chain is propane,
and the amine functional group takes the suffix "-amine". Numbering from the end closest to the
nitrogen gives the amino group at carbon 1. The correct IUPAC name is propan-1-amine.
"Propylamine" is a common name, and "1-aminopropane" is an acceptable but less preferred
alternative.
2. Which of the following correctly ranks the following amines in order of increasing boiling point:
trimethylamine, methylamine, dimethylamine?
A) Trimethylamine < dimethylamine < methylamine
B) Methylamine < dimethylamine < trimethylamine
C) Trimethylamine < methylamine < dimethylamine
D) Dimethylamine < methylamine < trimethylamine
Correct Answer: Trimethylamine < methylamine < dimethylamine
Rationale: Boiling point in amines is influenced by molecular weight and hydrogen bonding. Primary
amines have the strongest hydrogen bonds (two N-H bonds), secondary amines have one N-H bond,
and tertiary amines have no N-H bonds (only weaker dipole-dipole and London forces). However,
branching also matters. The order of increasing boiling point is trimethylamine (lowest, no H-bonding)
< methylamine (primary) < dimethylamine (secondary, higher molecular weight than methylamine).
,3. Which of the following is the major product of the reaction of benzene with bromine in the
presence of FeBr₃?
A) Bromobenzene
B) Benzene (no reaction)
C) 1,2-dibromobenzene
D) 1,3-dibromobenzene
Correct Answer: Bromobenzene
Rationale: Benzene undergoes electrophilic aromatic substitution (EAS) with bromine in the presence
of a Lewis acid catalyst (FeBr₃) to form bromobenzene. The reaction introduces a single bromine atom
onto the ring. Further bromination is possible but requires more vigorous conditions, so the major
product of the monosubstitution is bromobenzene.
4. Which of the following is the correct structure for N,N-dimethylpropan-1-amine?
A) CH₃-CH₂-CH₂-N(CH₃)₂
B) CH₃-CH₂-CH₂-NH-CH₃
C) CH₃-CH₂-CH₂-NH₂
D) (CH₃)₂CH-NH-CH₃
Correct Answer: CH₃-CH₂-CH₂-N(CH₃)₂
Rationale: The parent chain is propan-1-amine (a three-carbon chain with the amino group at C1). The
"N,N-dimethyl" prefix indicates that two methyl groups are attached to the nitrogen atom. Therefore,
the structure is CH₃-CH₂-CH₂-N(CH₃)₂. The other options represent different amines: CH₃-CH₂-CH₂-NH-
CH₃ is N-methylpropan-1-amine, CH₃-CH₂-CH₂-NH₂ is propan-1-amine, and (CH₃)₂CH-NH-CH₃ is N-
methylpropan-2-amine.
5. In the nitration of benzene, what is the electrophile that attacks the aromatic ring?
A) NO₂⁺ (nitronium ion)
B) NO₂⁻ (nitrite ion)
, C) HNO₃ (nitric acid)
D) NO (nitric oxide)
Correct Answer: NO₂⁺ (nitronium ion)
Rationale: In the nitration of benzene, concentrated nitric acid (HNO₃) is protonated by sulfuric acid
(H₂SO₄), leading to the formation of the nitronium ion (NO₂⁺). This highly electrophilic species is the
active electrophile that attacks the aromatic ring. The nitronium ion is a strong electrophile due to the
positive charge on nitrogen.
6. Which of the following amines is the most basic in aqueous solution?
A) Ammonia
B) Methylamine
C) Dimethylamine
D) Trimethylamine
Correct Answer: Dimethylamine
Rationale: In aqueous solution, the basicity of amines is influenced by both the electron-donating
effect of alkyl groups and solvation of the ammonium ion. For aliphatic amines in water, the order of
basicity is generally secondary > primary > tertiary > ammonia. Dimethylamine (secondary) is the most
basic due to a balance of inductive effects and solvation. Trimethylamine is less basic than
dimethylamine due to steric hindrance to solvation.
7. What is the product of the reaction of aniline (C₆H₅NH₂) with nitrous acid (HNO₂) at 0-5°C?
A) Benzenediazonium chloride
B) Nitrobenzene
C) Phenol
D) Chlorobenzene
Correct Answer: Benzenediazonium chloride
