What is the IUPAC name for the simplest aliphatic ketone?

The simplest aliphatic ketone is acetone, which is also known by its systematic IUPAC name, propan-2-one. A ketone is defined by having a carbonyl group (C=O) bonded to two carbon atoms. In the case of acetone, the carbonyl carbon is connected to two methyl (CH3) groups.

Being the simplest aliphatic ketone, it contains three carbon atoms in total, making it the smallest member of the ketone family. This distinguishes it from other options: propyl alcohol is an alcohol, ethylene is an alkene, and butanone is a longer-chain ketone. The structure and functional group dictate the classification, hence acetone is recognized as the simplest aliphatic ketone due to its fewest carbon atoms while still retaining the ketone functional group.