In the IUPAC system, how are aliphatic carboxylic acids named, and what is the numbering convention for the carbon chain?

In the IUPAC system, aliphatic carboxylic acids are named by identifying the longest continuous carbon chain containing the carboxyl group. The carbon chain is numbered from the carbon of the carboxyl group, and the suffix “-oic acid” is added to the root name of the alkane. The position of the carboxyl carbon is indicated by its numerical location in the chain. For example, CH₃CH₂COOH is systematically named as propanoic acid, reflecting the three-carbon chain and the carboxyl group at carbon 2. This systematic nomenclature provides a clear and standardized way to name aliphatic carboxylic acids based on their structure.