Quiz - Aldehydes and Ketones - 3 | Aldehydes and Ketones - Part 1

Organic Chemistry 2 - Quiz - Aldehydes and Ketones - 3

1

How would you correctly name an aldehyde with a four-carbon chain?

Aldehydes are named by replacing the terminal -e of the corresponding alkane with -al. Therefore, a four-carbon chain aldehyde is named butanal.

2

What is the correct IUPAC name for CH3CH2C(=O)CH2CH3?

The carbonyl group of a ketone is located within the carbon chain. The correct IUPAC nomenclature requires numbering the chain from the end nearest the carbonyl group. In this case, '3-pentanone' indicates that the ketone group is on the third carbon of a five-carbon chain.

3

What is a common method for synthesizing aldehydes from primary alcohols?

Primary alcohols can be selectively oxidized to aldehydes using pyridinium chlorochromate (PCC) without further oxidation to carboxylic acids, which makes it a common method for such conversions.

4

What is a common method for the preparation of ketones?

Friedel-Crafts acylation involves the reaction of an acyl chloride or an acid anhydride with an aromatic hydrocarbon in the presence of a Lewis acid catalyst. This method is commonly used for the synthesis of ketones.

5

Which reaction is a direct method for converting a secondary alcohol to a ketone?

Oxidation of a secondary alcohol with oxidizing agents, such as chromates or permanganates, directly converts it into a ketone.

6

Which reaction does not form a carbon-carbon bond in aldehyde or ketone chemistry?

The addition of water, or hydration, to aldehydes or ketones results in the formation of hydrates—compounds with an -OH group added to the carbonyl carbon—but does not form a new carbon-carbon bond.

7

Which of the following compounds can form a cyclic hemiacetal?

Hemiacetals can be formed when alcohols react with aldehydes. A cyclic hemiacetal can form when the -OH group and the aldehyde group are part of the same molecule, which is possible with 2-hydroxypropanal, a hydroxyaldehyde.

8

During nucleophilic addition to a carbonyl group, what role does the carbonyl carbon play?

The partial positive charge on the carbonyl carbon makes it an electrophilic center that is attacked by nucleophiles during addition reactions, such as in the formation of hydrates and hemiacetals.

9

What is the outcome of the reaction between a ketone and ethylene glycol in acidic conditions?

In the presence of ethylene glycol (a diol) and acidic conditions, a ketone can form a cyclic acetal (more specifically called a ketal) by reacting with both -OH groups of the diol.