CHEM 219 PRINCIPLES OF ORGANIC
CHEMISTRY - MODULE 4 EXAM
COMPREHENSIVE QUESTION BANK WITH
RATIONALES
SECTION 1: IUPAC NOMENCLATURE (Questions 1-20)
Question 1
Name the following compound using IUPAC systematic
nomenclature: Trans-1-bromo-3-chloro-cyclopentane
Answer: Trans-1-bromo-3-chloro-cyclopentane
Rationale: The parent chain is cyclopentane. Bromine and
chlorine substituents are at positions 1 and 3, respectively.
The trans configuration indicates substituents are on opposite
sides of the ring.
Question 2
Provide the IUPAC name for: 5-bromo-3-chloro-3-
ethylheptane
Answer: 5-bromo-3-chloro-3-ethylheptane
,Rationale: The parent chain is heptane with bromine at C5,
chlorine at C3, and ethyl group at C3. Numbering gives lowest
set of locants.
Question 3
Name the following aromatic compound: 1,2,4-
trichlorobenzene
Answer: 1,2,4-trichlorobenzene
Rationale: Benzene ring with three chlorine substituents at
1,2,4 positions. The lowest locant set is 1,2,4 (not 1,3,4 or
1,3,5).
Question 4
Name the compound: 4-ethyl-2-methylhexane
Answer: 4-ethyl-2-methylhexane
Rationale: Parent chain is hexane with ethyl at C4 and methyl
at C2. Numbering from the end giving lowest substituent
locants.
Question 5
,Name the compound: cis-1,2-dichlorocyclopropane
Answer: cis-1,2-dichlorocyclopropane
Rationale: Cyclopropane ring with chlorine substituents at
positions 1 and 2. Cis indicates both substituents on the same
side.
Question 6
Provide the IUPAC name for: 3-bromo-2-chloro-4-
methylpentane
Answer: 3-bromo-2-chloro-4-methylpentane
Rationale: Pentane parent with bromo at C3, chloro at C2,
methyl at C4. Alphabetical order for substituents.
Question 7
Name the compound: 4-fluoro-2,3-dimethylhexane
Answer: 4-fluoro-2,3-dimethylhexane
Rationale: Hexane parent with fluoro at C4, methyl groups at
C2 and C3.
, Question 8
Name: 1-iodo-2,2-dimethylpropane
Answer: 1-iodo-2,2-dimethylpropane (neopentyl iodide)
Rationale: Propane chain with iodine at C1 and two methyl
groups at C2.
Question 9
Name the compound: 2,3-dibromo-4-ethylheptane
Answer: 2,3-dibromo-4-ethylheptane
Rationale: Heptane parent with bromo at C2, C3 and ethyl at
C4.
Question 10
Name: 1,4-dichloro-2-methylbenzene
Answer: 1,4-dichloro-2-methylbenzene
Rationale: Benzene ring with chloro at 1,4 and methyl at 2.
Also known as 2,5-dichlorotoluene.
Question 11
CHEMISTRY - MODULE 4 EXAM
COMPREHENSIVE QUESTION BANK WITH
RATIONALES
SECTION 1: IUPAC NOMENCLATURE (Questions 1-20)
Question 1
Name the following compound using IUPAC systematic
nomenclature: Trans-1-bromo-3-chloro-cyclopentane
Answer: Trans-1-bromo-3-chloro-cyclopentane
Rationale: The parent chain is cyclopentane. Bromine and
chlorine substituents are at positions 1 and 3, respectively.
The trans configuration indicates substituents are on opposite
sides of the ring.
Question 2
Provide the IUPAC name for: 5-bromo-3-chloro-3-
ethylheptane
Answer: 5-bromo-3-chloro-3-ethylheptane
,Rationale: The parent chain is heptane with bromine at C5,
chlorine at C3, and ethyl group at C3. Numbering gives lowest
set of locants.
Question 3
Name the following aromatic compound: 1,2,4-
trichlorobenzene
Answer: 1,2,4-trichlorobenzene
Rationale: Benzene ring with three chlorine substituents at
1,2,4 positions. The lowest locant set is 1,2,4 (not 1,3,4 or
1,3,5).
Question 4
Name the compound: 4-ethyl-2-methylhexane
Answer: 4-ethyl-2-methylhexane
Rationale: Parent chain is hexane with ethyl at C4 and methyl
at C2. Numbering from the end giving lowest substituent
locants.
Question 5
,Name the compound: cis-1,2-dichlorocyclopropane
Answer: cis-1,2-dichlorocyclopropane
Rationale: Cyclopropane ring with chlorine substituents at
positions 1 and 2. Cis indicates both substituents on the same
side.
Question 6
Provide the IUPAC name for: 3-bromo-2-chloro-4-
methylpentane
Answer: 3-bromo-2-chloro-4-methylpentane
Rationale: Pentane parent with bromo at C3, chloro at C2,
methyl at C4. Alphabetical order for substituents.
Question 7
Name the compound: 4-fluoro-2,3-dimethylhexane
Answer: 4-fluoro-2,3-dimethylhexane
Rationale: Hexane parent with fluoro at C4, methyl groups at
C2 and C3.
, Question 8
Name: 1-iodo-2,2-dimethylpropane
Answer: 1-iodo-2,2-dimethylpropane (neopentyl iodide)
Rationale: Propane chain with iodine at C1 and two methyl
groups at C2.
Question 9
Name the compound: 2,3-dibromo-4-ethylheptane
Answer: 2,3-dibromo-4-ethylheptane
Rationale: Heptane parent with bromo at C2, C3 and ethyl at
C4.
Question 10
Name: 1,4-dichloro-2-methylbenzene
Answer: 1,4-dichloro-2-methylbenzene
Rationale: Benzene ring with chloro at 1,4 and methyl at 2.
Also known as 2,5-dichlorotoluene.
Question 11
