Which can be oxidized into carboxylic acids: aldehydes, or ketones?
What tests differentiate a sample of an aldehyde from a sample of a ketone?

• A. Aldehydes can be oxidized into carboxylic acids. Strong oxidizing agents such as potassium permanganate (KMnO₄) or m-chloroperoxybenzoic acid (m-CPBA) are used to differentiate a sample of an aldehyde from a sample of a ketone: aldehydes will show a positive result, while ketones will show no reaction.
• B. Aldehydes can be oxidized into carboxylic acids. Tollens' test and Benedict's test are used to differentiate a sample of an aldehyde from a sample of a ketone: aldehydes will show a positive result, while ketones will show no reaction.
• C. Ketones can be oxidized into carboxylic acids. Strong oxidizing agents such as potassium permanganate (KMnO₄) or m-chloroperoxybenzoic acid (m-CPBA) are used to differentiate a sample of an aldehyde from a sample of a ketone: ketones will show a positive result, while aldehydes will show no reaction.
• D. Ketones can be oxidized into carboxylic acids. Tollens' test and Benedict's test are used to differentiate a sample of an aldehyde from a sample of a ketone: ketones will show a positive result, while aldehydes will show no reaction.

Answer: (B)