Chain isomerism
What is here?
You can see models of the three chain isomers of pentane, C5H12. You can also see the structural and displayed formulae for these alkanes.
2-methylbutane
2,2-dimethylpropane
pentane
Branches
Pentane is the unbranched “straight chain” isomer of C5H12. The other two isomers are branched:
- 2-methylbutane has one branch
- 2,2-dimethylpropane has two branches.
Each of these branches contains one carbon atom and is a methyl group, —CH3.
Structural and displayed formulae
A structural formula shows the number of atoms of each element in a molecule, and their positions in the molecule.
A displayed formula shows the same information as a structural formula, but in addition it shows the bonds between the atoms.
Name of alkane | Structural formula | Displayed formula |
---|---|---|
2-methylbutane | (CH3)2CHCH2CH3 | |
2,2-dimethylpropane | C(CH3)4 | |
pentane | CH3(CH2)3CH3 |