Question 1

Which reagent is commonly used to oxidize a primary alcohol to an aldehyde without further oxidation to a carboxylic acid?

Accepted Answer

Pyridinium chlorochromate (PCC)

Question 2

What is the major organic product when 2-butanol is treated with Na\_2Cr\_2O\_7 and H\_2SO\_4?

Accepted Answer

$$\mathrm{CH_3CH_2COCH_3} (2-$$butanone)

Question 3

Which alcohol is most resistant to oxidation by chromic acid?

Accepted Answer

tert-butyl alcohol

Question 4

During the oxidation of a primary alcohol with Na\_2Cr\_2O\_7/H\_2SO\_4, which intermediate is formed before the carboxylic acid?

Accepted Answer

Aldehyde

Question 5

Which color change is observed when a secondary alcohol is oxidized with Na\_2Cr\_2O\_7/H\_2SO\_4?

Accepted Answer

Orange to greenish-blue

Question 6

What is the role of the chromate ester in the oxidation mechanism of alcohols?

Accepted Answer

It is the intermediate that facilitates the transfer of oxygen to the alcohol.

Question 7

Which of the following best describes the oxidation state change of the carbon atom in a primary alcohol during oxidation to a carboxylic acid?

Accepted Answer

Increase in oxidation state

Question 8

A student treats cyclohexanol with PCC. What is the expected product?

Accepted Answer

Cyclohexanone

Question 9

Which of the following statements about the oxidation of tertiary alcohols is correct?

Accepted Answer

Tertiary alcohols are resistant to oxidation because they cannot lose two hydrogens.

Question 10

Which reagent is used in the Swern oxidation to convert primary alcohols to aldehydes?

Accepted Answer

Dimethylsulfoxide (DMSO), oxalyl chloride, and a hindered base

Question 11

In biological systems, which enzyme catalyzes the oxidation of ethanol to acetaldehyde?

Accepted Answer

Alcohol dehydrogenase (ADH)

Question 12

Methanol poisoning is treated with excess ethanol because:

Accepted Answer

Ethanol competes for alcohol dehydrogenase, slowing the formation of toxic formaldehyde.

Question 13

Which of the following is NOT a typical reaction of alcohols?

Accepted Answer

Reduction to form alkyl halides

Question 14

What is the product when 1-hexanol is oxidized with sodium hypochlorite (NaOCl)?

Accepted Answer

Hexanal

Question 15

Which of the following best describes the change in the chromium oxidation state during the oxidation of alcohols with Na\_2Cr\_2O\_7?

Accepted Answer

Cr(VI) is reduced to Cr(III)

Question 16

Which of the following is a correct statement about the use of PCC in alcohol oxidation?

Accepted Answer

PCC oxidizes secondary alcohols to ketones.

Question 17

Which of the following is a correct description of the oxidation mechanism of alcohols with chromic acid?

Accepted Answer

Formation of a chromate ester followed by elimination to form the carbonyl compound.

Question 18

Which of the following is the correct order of reactivity of alcohols with HBr (most reactive first)?

Accepted Answer

3° \u003e 2° \u003e 1°

Question 19

Which of the following is a correct statement about the dehydration of alcohols?

Accepted Answer

Dehydration of alcohols generally proceeds via an E1 mechanism.

Reactions of Alcohols – Organic Chemistry III Study Notes

Study Guide - Practice Questions