Question 1

Which of the following best describes the carbonyl group?

Accepted Answer

A functional group consisting of a carbon atom double-bonded to an oxygen atom ($\mathrm{C=O}$)

Question 2

Which statement correctly explains the polarity of the carbonyl group?

Accepted Answer

The oxygen atom is more electronegative than carbon, creating a partial negative charge on oxygen and a partial positive charge on carbon.

Question 3

Which of the following is the correct IUPAC name for the structure below?

$\mathrm{CH_3CH_2CH_2CHO}$

Accepted Answer

Butanal

Question 4

Aldehydes and ketones have higher boiling points than alkanes of similar molecular weight. What is the main reason for this?

Accepted Answer

Aldehydes and ketones have dipole-dipole interactions due to the polar carbonyl group.

Question 5

Which of the following molecules is most soluble in water?

Accepted Answer

Acetone ($\mathrm{CH_3COCH_3}$)

Question 6

Which of the following is the product of the reduction of 3-methyl-2-pentanone?

Accepted Answer

3-methyl-2-pentanol

Question 7

Which reagent is commonly used to test for the presence of aldehydes but not ketones?

Accepted Answer

Tollens' reagent ($\mathrm{Ag(NH_3)_2^+}$)

Question 8

What is the main difference between the oxidation of aldehydes and ketones?

Accepted Answer

Aldehydes can be oxidized to carboxylic acids, while ketones are generally resistant to oxidation.

Question 9

Which of the following compounds is classified as a hemiacetal?

Accepted Answer

A molecule with one $-OH$ and one $-OR$ group attached to the same carbon

Question 10

During the formation of an acetal from an aldehyde, which of the following steps occurs first?

Accepted Answer

Addition of an alcohol to the carbonyl carbon to form a hemiacetal

Question 11

Which of the following best explains why simple aldehydes and ketones are soluble in water?

Accepted Answer

They can accept hydrogen bonds from water due to the lone pairs on the oxygen atom.

Question 12

Which of the following is the correct product of the hydrolysis of the acetal below?

$\mathrm{CH_3CH(OCH_3)_2}$ + $\mathrm{H_2O}$ $\rightarrow$ ?

Accepted Answer

$\mathrm{CH_3CHO}$ (acetaldehyde)

Question 13

Which of the following statements about formaldehyde ($\mathrm{HCHO}$) is true?

Accepted Answer

It is a gas at room temperature and is used as a disinfectant and preservative.

Question 14

Which of the following is a correct statement about the reduction of ketones?

Accepted Answer

Ketones are reduced to secondary alcohols by addition of hydrogen across the carbonyl bond.

Question 15

Which of the following is the best classification for the molecule below?

$\mathrm{CH_3CH(OH)OCH_3}$

Accepted Answer

Hemiacetal

Question 16

Which of the following statements about acetone ($\mathrm{CH_3COCH_3}$) is correct?

Accepted Answer

It is miscible with water and is widely used as a solvent in organic chemistry.

Question 17

Which of the following is true about the formation of acetals and ketals?

Accepted Answer

Acetals are formed from aldehydes and ketals are formed from ketones by reaction with alcohols under acidic conditions.

Question 18

Which of the following is a common use of benzaldehyde?

Accepted Answer

As a flavoring agent in foods and perfumes

Question 19

Which of the following best describes the process of acetal hydrolysis?

Accepted Answer

A reaction in which a bond is broken and the atoms of water add to the atoms of the broken bond, converting an acetal back to an aldehyde or ketone.

Aldehydes and Ketones: Structure, Properties, and Reactions (GOB Chemistry Study Notes)

Study Guide - Practice Questions