⚙️ Learning Objectives Classify oxygen-containing organic compounds based on the structure of the functional group that is present. Identify hydroxyl groups, carbonyl groups, and carboxyl groups within oxygen-containing organic compounds. Oxygen-containing organic compounds may be classified based on the structural arrangement of oxygen atoms in relation to the carbon and hydrogen atoms within a molecule. Such structural arrangements often allow oxygen-containing compounds to function in a similar manner chemically and physically from molecule-to-molecule and are called functional groups . Figure \(\PageIndex{1}\) shows three common oxygen-containing functional groups found in organic molecules. Classifying Oxygen-Containing Organic Compounds The functional groups shown in Figure \(\PageIndex{1}\) are just three of many different functional groups. However, the presence and location of functional groups in organic molecules allows us to lump them together into different classes that function similarly, both chemically and physically. Table \(\PageIndex{1}\) shows the classification of several types of oxygen-containing organic compounds. Though the list is not complete, it provides some perspective as to the wide variety of oxygen-containing organic compounds that are possible. Notice the presence of the functional groups shown above in the different families of compounds. The letter R represents an alkyl group (or more generally, a hydrocarbon group). As a reminder, molecular models rendered with JSmol may be manipulated by grabbing the molecules and rotating it to your desired orientation. Family Structure Example alcohol NaN NaN aldehyde NaN NaN ketone NaN NaN carboxylic acid NaN NaN ester NaN NaN ether NaN NaN ✅ Example \(\PageIndex{1}\) Classify each molecule as an alcohol, aldehyde, ketone, carboxylic acid, ether, or ester. CH 3 OH Solution This molecule has an alkyl group that is bonded to a carbon atom that is double bonded to an oxygen atom and single bonded to a hydrogen atom. This gives it a general formula that fits an aldehyde, . This molecule has an alkyl group attached to each side of a carbonyl group, . This gives it a general formula that fits a ketone, . This molecule has an alkyl group attached to each side of an oxygen atom. This gives it a general formula that fits an ether, . This molecule has an alkyl group attached to a hydroxyl group, . This gives it a general formula that fits an alcohol, . ✏️ Exercise \(\PageIndex{1}\) Classify each molecule as an alcohol, aldehyde, ketone, carboxylic acid, ether, or ester. CH 3 OCH 2 CH 2 CH 2 CH 3 Answer A alcohol Answer B ester Answer C ether Answer D carboxylic acid This page is shared under a CC BY-NC-SA 4.0 licenses and was authored, remixed, and/or curated by Lance S. Lund (Anoka-Ramsey Community College). Original source: https://openstax.org/details/books/chemistry-2e . LICENSED UNDER