Why does straight and long chain butane has greater boiling point than branched and short chain 2-methyl propane with the same number of electrons?

1 Answer
Feb 20, 2018

Why is it easier to untangle short pieces of string than untangle longer pieces of string?

Explanation:

But first we should look at some data. The normal boiling point of #"n-butane"# is #-1# #""^@C#. The normal boiling point of #"isobutane"# is #-11.7# #""^@C#.

The longer chain butane has greater opportunity to interact with other molecules by dispersion forces, and this is nicely illustrated by the progressive increase in boiling points, as we go from #"methane"# to #"ethane"# to ...#"n-pentane"# to #"n-hexane"# to #"n-heptane..."#