$$ \text{Ethanol} \xrightarrow{ADH} \text{Acetaldehyde} \xrightarrow{ALDH} \text{Acetic acid} $$

Question 1

Which of the following is the correct product when a primary alcohol is oxidized using pyridinium chlorochromate (PCC)?

Accepted Answer

An aldehyde

Question 2

What is the main product when a secondary alcohol undergoes oxidation with chromic acid?

Accepted Answer

Ketone

Question 3

Why are tertiary alcohols resistant to oxidation under normal conditions?

Accepted Answer

They lack a hydrogen atom on the carbon bearing the hydroxyl group

Question 4

Which reagent is most suitable for oxidizing a primary alcohol to a carboxylic acid?

Accepted Answer

Chromic acid

Question 5

In the hepatic enzymatic oxidation of ethanol, which coenzyme is reduced?

Accepted Answer

NAD+ is reduced to NADH

Question 6

Methanol poisoning can cause blindness and death due to its metabolism to which toxic compound?

Accepted Answer

Formic acid

Question 7

What is the rationale for using intravenous ethanol as an antidote in methanol poisoning?

Accepted Answer

Ethanol competes for alcohol dehydrogenase, slowing methanol metabolism

Question 8

Which of the following best describes the oxidation of phenol with an oxidizing agent?

Accepted Answer

Phenol is oxidized to a quinone

Question 9

Which of the following is a biological quinone involved in electron transport?

Accepted Answer

Ubiquinone (Coenzyme Q)

Question 10

During the bromination of phenol in aqueous NaOH, what is the major product?

Accepted Answer

2,4,6-tribromophenol

Question 11

Which position does the nitro group preferentially occupy during the nitration of 4-methylphenol?

Accepted Answer

Ortho to the hydroxyl group

Question 12

In the sulfonation of phenol, which product is favored at low temperature?

Accepted Answer

Ortho-sulfonated phenol

Question 13

Which of the following statements about phenolic antioxidants is correct?

Accepted Answer

They prevent oxidation in pharmaceutical products

Question 14

What is the main antimicrobial mode of action of phenol at high concentrations?

Accepted Answer

Denaturation of bacterial proteins

Question 15

Which of the following best explains why p-nitrophenol is less volatile than o-nitrophenol?

Accepted Answer

p-Nitrophenol forms intermolecular hydrogen bonds

Question 16

A chronic alcoholic requires a much larger dose of ethanol as an antidote for methanol poisoning because:

Accepted Answer

Their liver produces more alcohol dehydrogenase

Question 17

Which of the following is the correct sequence for the enzymatic oxidation of ethanol in the liver?

Accepted Answer

$$ 	ext{Ethanol} \xrightarrow{ADH} 	ext{Acetaldehyde} \xrightarrow{ALDH} 	ext{Acetic acid} $$

Question 18

Which of the following is a naturally occurring phenol with antibiotic properties?

Accepted Answer

Chloramphenicol

Question 19

Which of the following best describes the effect of 70-75% ethyl or isopropyl alcohol as a disinfectant?

Accepted Answer

It denatures bacterial proteins and disrupts membranes

Question 20

Which of the following statements about the electrophilic substitution of phenols is correct?

Accepted Answer

The hydroxyl group is ortho/para-directing

Alcohols & Phenols: Oxidation, Reactions, and Biological Importance

Study Guide - Practice Questions