Summarizing Aldehydes, Ketones, Carboxylic Acids, and Esters

Key Concepts and Summary

Functional groups related to the carbonyl group include the –CHO group of an aldehyde, the –CO– group of a ketone, the –CO₂H group of a carboxylic acid, and the –CO₂R group of an ester. The carbonyl group, a carbon-oxygen double bond, is the key structure in these classes of organic molecules:

Aldehydes contain at least one hydrogen atom attached to the carbonyl carbon atom, ketones contain two carbon groups attached to the carbonyl carbon atom, carboxylic acids contain a hydroxyl group attached to the carbonyl carbon atom, and esters contain an oxygen atom attached to another carbon group connected to the carbonyl carbon atom. All of these compounds contain oxidized carbon atoms relative to the carbon atom of an alcohol group.

Glossary

aldehyde

organic compound containing a carbonyl group bonded to two hydrogen atoms or a hydrogen atom and a carbon substituent

carbonyl group

carbon atom double bonded to an oxygen atom

carboxylic acid

organic compound containing a carbonyl group with an attached hydroxyl group

ester

organic compound containing a carbonyl group with an attached oxygen atom that is bonded to a carbon substituent

ketone

organic compound containing a carbonyl group with two carbon substituents attached to it