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How can the aldehyde group be identified in a condensed structural formula?

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oxidation of alcohols — aldehyde Alcohols may be oxidized to give aldehydes, ketones, and carboxylic acids. The oxidation of organic compounds generally increases the number of bonds from carbon to oxygen, and it may decrease the number of bonds to hydrogen.

In condensed structural formulas, the aldehyde group is identified by the symbol CHO.1

This notation represents the carbonyl group—a carbon atom double-bonded to an oxygen atom—which is also bonded to a hydrogen atom. While the carbonyl group is a feature of both aldehydes and ketones, the presence of this specific hydrogen atom on the carbonyl carbon is what distinguishes an aldehyde from a ketone, where the carbonyl carbon is instead bonded to two other carbon atoms.1234

For example, the formula for formaldehyde is written as HCHO, and acetaldehyde is written as CH₃CHO.1