Common name: A nomenclature system useful for naming simple organic molecules. It often fails for more complex molecules, in which case systematic or (better yet) IUPAC nomenclature is preferable. The prefix "n-" (or normal) is used when all carbons size a continuous, unbranched (linear) chain. If a functional group (such as an alcohol) is present that functional group is on the end of the chain. Not lớn be confused with "nor", which indicates a missing methyl group.
Common name: neopentane IUPAC name: 2,2-dimethylpropane
Common name: neopentyl alcohol IUPAC name: 2,2-dimethyl-1-propanol
The prefix "sec" or "s" is used when the functional group is bonded to a secondary carbon. This prefix is only useful for a four-carbon chain. It is not applicable with a shorter chain, & it is often ambiguous when the chain has five or more carbons.