Which compound is commonly known as isopropanol?

Isopropanol, also known as isopropyl alcohol, is the common name for 2-propanol. This designation reflects its chemical structure, where the hydroxyl (-OH) group is attached to the second carbon in the three-carbon propane chain. The "iso" prefix in its name indicates the presence of a branched structure, which is characteristic of this particular alcohol.

In organic nomenclature, the systematic naming of alcohols follows specific rules. The longest carbon chain containing the hydroxyl group is identified, and the position of the hydroxyl group is indicated by the number of the carbon atom to which it is attached. In the case of 2-propanol, it clearly communicates both the structure and the functional group.

The other options refer to different alcohols with distinct structures and names. For instance, 1-butanol has a straight chain of four carbons with the hydroxyl group at the first carbon, ethyl alcohol (or ethanol) has two carbons, and 3-pentanol has a five-carbon chain with the hydroxyl group at the third carbon. These differences highlight the specificity of organic nomenclature, reinforcing the importance of understanding compound names in terms of their structural attributes. Thus, 2