CHEM 219 - ORGANIC CHEM
OBJECTIVE ASSESSMENT - EXAM
CHEM 219 Module 6 Exam
(2026/2027) - Principles of
Organic Chemistry
Portage Learning Verified Qs & Ans 2026/2027
50 100%
QUESTIONS VERIFIED ANSWERS EDITION
TOPICS COVERED
IUPAC Nomenclature Functional Group Properties
Stereochemistry & Chirality Organic Synthesis
Reaction Mechanisms Spectroscopic Analysis
COVER PAGE - 1
,SECTION 1 | Nomenclature & Structure | Q1-Q10 | CHEM 219 2026/2027
Q1 Question 1 of 50
Q1. A 19-year-old undergraduate is reviewing IUPAC rules for naming branched alkanes. She
encounters a compound with a five-carbon parent chain and two methyl substituents at
positions 2 and 4. What is the correct systematic name for this alkane?
A. 2,4-dimethylpentane
B. 2,4-dimethylbutane
C. 3,5-dimethylpentane
D. 2,4-ethylpentane
Correct Answer: A
Rationale:
The parent chain contains five carbons (pentane), and two methyl groups are located at carbons 2 and 4, giving
2,4-dimethylpentane. Option B incorrectly identifies the parent chain as butane, while C uses incorrect numbering and D
incorrectly uses an ethyl substituent.
Q2 Question 2 of 50
Q2. During a laboratory session, a student isolates an alkene with the molecular formula
C5H10 that contains a double bond between carbons 2 and 3 of a pentane chain. What is the
proper IUPAC name for this compound?
A. pent-2-ene
B. 2-pentene
C. pent-3-ene
D. 1-methylbut-1-ene
Correct Answer: A
Rationale:
According to current IUPAC recommendations, the locant is placed immediately before the suffix, giving pent-2-ene. While
2-pentene (B) is an older but still acceptable name, pent-3-ene (C) would represent the same compound but violates the
lowest locant rule, and D describes a different constitutional isomer.
CHEM 219 - 2026/2027 | Passing Score: 80% | Page 2 of 2
, SECTION 1 | Nomenclature & Structure | Q1-Q10 | CHEM 219 2026/2027
Q3 Question 3 of 50
Q3. A teaching assistant asks students to draw the skeletal structure of
3-ethyl-2,2-dimethylhexane. How many total carbon atoms are present in the longest
continuous carbon chain of this molecule?
A. Six
B. Five
C. Seven
D. Eight
Correct Answer: A
Rationale:
The parent name hexane indicates a six-carbon main chain. The ethyl and two methyl groups are substituents branching
off this chain, so the longest continuous chain contains six carbons. Option B would correspond to pentane, C to heptane,
and D to octane, all of which misidentify the parent chain.
Q4 Question 4 of 50
Q4. In an organic chemistry workshop, a professor presents a cyclic compound containing a
six-membered ring with alternating single and double bonds. What is the accepted IUPAC
name for this aromatic hydrocarbon?
A. Benzene
B. Cyclohexadiene
C. Cyclohexatriene
D. Phenylhexane
Correct Answer: A
Rationale:
Benzene is the retained trivial name for the aromatic six-membered ring with three conjugated double bonds. While
cyclohexatriene (C) describes the same connectivity, it is not the accepted IUPAC preferred name. Cyclohexadiene (B)
has only two double bonds, and phenylhexane (D) is a substituted alkane, not a pure aromatic ring.
CHEM 219 - 2026/2027 | Passing Score: 80% | Page 3 of 3
OBJECTIVE ASSESSMENT - EXAM
CHEM 219 Module 6 Exam
(2026/2027) - Principles of
Organic Chemistry
Portage Learning Verified Qs & Ans 2026/2027
50 100%
QUESTIONS VERIFIED ANSWERS EDITION
TOPICS COVERED
IUPAC Nomenclature Functional Group Properties
Stereochemistry & Chirality Organic Synthesis
Reaction Mechanisms Spectroscopic Analysis
COVER PAGE - 1
,SECTION 1 | Nomenclature & Structure | Q1-Q10 | CHEM 219 2026/2027
Q1 Question 1 of 50
Q1. A 19-year-old undergraduate is reviewing IUPAC rules for naming branched alkanes. She
encounters a compound with a five-carbon parent chain and two methyl substituents at
positions 2 and 4. What is the correct systematic name for this alkane?
A. 2,4-dimethylpentane
B. 2,4-dimethylbutane
C. 3,5-dimethylpentane
D. 2,4-ethylpentane
Correct Answer: A
Rationale:
The parent chain contains five carbons (pentane), and two methyl groups are located at carbons 2 and 4, giving
2,4-dimethylpentane. Option B incorrectly identifies the parent chain as butane, while C uses incorrect numbering and D
incorrectly uses an ethyl substituent.
Q2 Question 2 of 50
Q2. During a laboratory session, a student isolates an alkene with the molecular formula
C5H10 that contains a double bond between carbons 2 and 3 of a pentane chain. What is the
proper IUPAC name for this compound?
A. pent-2-ene
B. 2-pentene
C. pent-3-ene
D. 1-methylbut-1-ene
Correct Answer: A
Rationale:
According to current IUPAC recommendations, the locant is placed immediately before the suffix, giving pent-2-ene. While
2-pentene (B) is an older but still acceptable name, pent-3-ene (C) would represent the same compound but violates the
lowest locant rule, and D describes a different constitutional isomer.
CHEM 219 - 2026/2027 | Passing Score: 80% | Page 2 of 2
, SECTION 1 | Nomenclature & Structure | Q1-Q10 | CHEM 219 2026/2027
Q3 Question 3 of 50
Q3. A teaching assistant asks students to draw the skeletal structure of
3-ethyl-2,2-dimethylhexane. How many total carbon atoms are present in the longest
continuous carbon chain of this molecule?
A. Six
B. Five
C. Seven
D. Eight
Correct Answer: A
Rationale:
The parent name hexane indicates a six-carbon main chain. The ethyl and two methyl groups are substituents branching
off this chain, so the longest continuous chain contains six carbons. Option B would correspond to pentane, C to heptane,
and D to octane, all of which misidentify the parent chain.
Q4 Question 4 of 50
Q4. In an organic chemistry workshop, a professor presents a cyclic compound containing a
six-membered ring with alternating single and double bonds. What is the accepted IUPAC
name for this aromatic hydrocarbon?
A. Benzene
B. Cyclohexadiene
C. Cyclohexatriene
D. Phenylhexane
Correct Answer: A
Rationale:
Benzene is the retained trivial name for the aromatic six-membered ring with three conjugated double bonds. While
cyclohexatriene (C) describes the same connectivity, it is not the accepted IUPAC preferred name. Cyclohexadiene (B)
has only two double bonds, and phenylhexane (D) is a substituted alkane, not a pure aromatic ring.
CHEM 219 - 2026/2027 | Passing Score: 80% | Page 3 of 3
