Structural Isomers of Pentane and Hexane: Formulas and Names

Structural Isomers of Pentane

The three isomers of pentane are:

1. n-pentane: CH3-CH2-CH2-CH2-CH3 (also called pentane)
2. 2-methylbutane: CH3-CH(CH3)-CH2-CH3
3. 2,2-dimethylpropane: (CH3)3-C-CH3

Structural Isomers of Hexane

The five isomers of hexane are:

1. n-hexane: CH3-CH2-CH2-CH2-CH2-CH3 (also called hexane)
2. 2-methylpentane: CH3-CH2-CH(CH3)-CH2-CH3
3. 3-methylpentane: CH3-CH(CH3)-CH2-CH2-CH3
4. 2,2-dimethylbutane: (CH3)3-C-CH2-CH3
5. 2,3-dimethylbutane: CH3-CH(CH3)-C(CH3)-CH3

Systematic (IUPAC) Names

The systematic (IUPAC) names of the compounds represented in the structural isomers of pentane and hexane are:

1. n-pentane
2. 2-methylbutane
3. 2,2-dimethylpropane
4. n-hexane
5. 2-methylpentane
6. 3-methylpentane
7. 2,2-dimethylbutane
8. 2,3-dimethylbutane

In summary, the names of the structural isomers of pentane and hexane are based on the arrangement of carbon atoms in the main chain and the presence of additional methyl groups. The IUPAC names follow a standardized set of rules for naming organic compounds.