CHEM 219 Module 5 Exam 2026 | Practice
Questions with Answers & Detailed Explanations |
Organic Chemistry II – Alcohols, Ethers,
Aldehydes, Ketones, Carboxylic Acids & Amines |
Portage Learning | Latest Update
📚 Section 1: Alcohols & Phenols (Questions 1–45)
1. Which of the following is the correct IUPAC name for the compound
CH₃CH(OH)CH₂CH₃?
A) 1-Butanol
B) 2-Butanol
C) Butan-2-ol
D) B and C
Answer: D
Explanation: The compound CH₃CH(OH)CH₂CH₃ is butan-2-ol, which can also be named
as 2-butanol. The hydroxyl group is on the second carbon of the butane chain. Both IUPAC
nomenclature systems are acceptable, though butan-2-ol is preferred by current IUPAC
rules.
, 2. Which of the following alcohols would be the most soluble in water?
A) 1-Octanol
B) 2-Octanol
C) Ethanol
D) Cyclohexanol
Answer: C
Explanation: Ethanol has the shortest carbon chain of the options, making it the most
soluble in water. Solubility of alcohols in water decreases as the length of the hydrophobic
hydrocarbon chain increases. Ethanol is completely miscible with water due to its ability to
form hydrogen bonds with water molecules.
3. The boiling points of alcohols are higher than those of alkanes with similar
molecular weights because:
A) Alcohols are more polar
B) Alcohols can form hydrogen bonds
C) Alcohols have higher molecular weights
D) Alcohols are less volatile
Answer: B
Explanation: Alcohols can form hydrogen bonds between molecules, which requires extra
energy to break during boiling. Alkanes only have weak London dispersion forces. The
, hydrogen bonding in alcohols significantly increases their boiling points compared to
alkanes of similar molecular weight.
4. Which of the following is the correct order of increasing acidity for alcohols?
A) Primary < Secondary < Tertiary
B) Tertiary < Secondary < Primary
C) Primary < Tertiary < Secondary
D) Secondary < Primary < Tertiary
Answer: B
Explanation: The acidity of alcohols follows the order: primary > secondary > tertiary. This is
due to the stabilization of the alkoxide ion by solvation and the inductive effect. Primary
alkoxides are more stable because they are less sterically hindered and better solvated.
5. The reagent commonly used to convert a primary alcohol to a carboxylic acid is:
A) PCC (Pyridinium Chlorochromate)
B) KMnO₄
C) H₂SO₄
D) NaBH₄
Answer: B
Explanation: Potassium permanganate (KMnO₄) is a strong oxidizing agent that can oxidize
, primary alcohols to carboxylic acids. PCC (A) is a milder oxidizing agent that will stop at the
aldehyde. H₂SO₄ (C) is a dehydrating agent, and NaBH₄ (D) is a reducing agent.
6. The Lucas test is used to distinguish between:
A) Primary, secondary, and tertiary alcohols
B) Alcohols and phenols
C) Alcohols and ethers
D) Aldehydes and ketones
Answer: A
Explanation: The Lucas test uses ZnCl₂ in concentrated HCl to distinguish between primary,
secondary, and tertiary alcohols based on the rate of alkyl chloride formation. Tertiary
alcohols react immediately (cloudiness appears), secondary alcohols react in 5-10 minutes,
and primary alcohols do not react at room temperature.
7. Phenols are more acidic than alcohols because:
A) Phenols have a higher pKa
B) The phenoxide ion is stabilized by resonance
C) Phenols have stronger hydrogen bonds
D) Phenols are less polar
Answer: B
Explanation: Phenols are more acidic than alcohols because the phenoxide ion is stabilized
Questions with Answers & Detailed Explanations |
Organic Chemistry II – Alcohols, Ethers,
Aldehydes, Ketones, Carboxylic Acids & Amines |
Portage Learning | Latest Update
📚 Section 1: Alcohols & Phenols (Questions 1–45)
1. Which of the following is the correct IUPAC name for the compound
CH₃CH(OH)CH₂CH₃?
A) 1-Butanol
B) 2-Butanol
C) Butan-2-ol
D) B and C
Answer: D
Explanation: The compound CH₃CH(OH)CH₂CH₃ is butan-2-ol, which can also be named
as 2-butanol. The hydroxyl group is on the second carbon of the butane chain. Both IUPAC
nomenclature systems are acceptable, though butan-2-ol is preferred by current IUPAC
rules.
, 2. Which of the following alcohols would be the most soluble in water?
A) 1-Octanol
B) 2-Octanol
C) Ethanol
D) Cyclohexanol
Answer: C
Explanation: Ethanol has the shortest carbon chain of the options, making it the most
soluble in water. Solubility of alcohols in water decreases as the length of the hydrophobic
hydrocarbon chain increases. Ethanol is completely miscible with water due to its ability to
form hydrogen bonds with water molecules.
3. The boiling points of alcohols are higher than those of alkanes with similar
molecular weights because:
A) Alcohols are more polar
B) Alcohols can form hydrogen bonds
C) Alcohols have higher molecular weights
D) Alcohols are less volatile
Answer: B
Explanation: Alcohols can form hydrogen bonds between molecules, which requires extra
energy to break during boiling. Alkanes only have weak London dispersion forces. The
, hydrogen bonding in alcohols significantly increases their boiling points compared to
alkanes of similar molecular weight.
4. Which of the following is the correct order of increasing acidity for alcohols?
A) Primary < Secondary < Tertiary
B) Tertiary < Secondary < Primary
C) Primary < Tertiary < Secondary
D) Secondary < Primary < Tertiary
Answer: B
Explanation: The acidity of alcohols follows the order: primary > secondary > tertiary. This is
due to the stabilization of the alkoxide ion by solvation and the inductive effect. Primary
alkoxides are more stable because they are less sterically hindered and better solvated.
5. The reagent commonly used to convert a primary alcohol to a carboxylic acid is:
A) PCC (Pyridinium Chlorochromate)
B) KMnO₄
C) H₂SO₄
D) NaBH₄
Answer: B
Explanation: Potassium permanganate (KMnO₄) is a strong oxidizing agent that can oxidize
, primary alcohols to carboxylic acids. PCC (A) is a milder oxidizing agent that will stop at the
aldehyde. H₂SO₄ (C) is a dehydrating agent, and NaBH₄ (D) is a reducing agent.
6. The Lucas test is used to distinguish between:
A) Primary, secondary, and tertiary alcohols
B) Alcohols and phenols
C) Alcohols and ethers
D) Aldehydes and ketones
Answer: A
Explanation: The Lucas test uses ZnCl₂ in concentrated HCl to distinguish between primary,
secondary, and tertiary alcohols based on the rate of alkyl chloride formation. Tertiary
alcohols react immediately (cloudiness appears), secondary alcohols react in 5-10 minutes,
and primary alcohols do not react at room temperature.
7. Phenols are more acidic than alcohols because:
A) Phenols have a higher pKa
B) The phenoxide ion is stabilized by resonance
C) Phenols have stronger hydrogen bonds
D) Phenols are less polar
Answer: B
Explanation: Phenols are more acidic than alcohols because the phenoxide ion is stabilized
