Final answer:
The structural formula for 3-methylpentane indicates a five-carbon chain with a methyl group on the third carbon, resulting in the name 3-methylpentane, specific to its unique structure.
Step-by-step explanation:
The structural formula for 3-methylpentane represents a molecule with the formula C6H14. In organic chemistry nomenclature, the longest chain of carbon atoms in the molecule is identified first, which in this case is a five-carbon chain, making it a pentane. A methyl group (a one-carbon substituent) is attached to the third carbon in the chain, which is indicated by the number 3, followed by a hyphen, the substituent name 'methyl', and the parent hydrocarbon name 'pentane', yielding the name 3-methylpentane. This naming convention is precise and specific to this molecular structure.
Examining how other molecules are named, we see similar rules applied. For example, the naming of 2,4-dimethyl-3-heptene indicates the presence of a double bond (indicated by the suffix '-ene') in a seven-carbon chain with two methyl groups at positions 2 and 4. Moreover, cis-trans isomers require a double bond and enantiomers require a central carbon to be connected to at least four different atoms or groups.