The behavior of the alkanes tends to be ideal in their general physical chemical behavior. As a consequence, it is important to examine other homologous series to ensure the validity of the argument. Data from the same source is available for a homologous series of aliphatic amines, alcohols, halogenated hydrocarbons etc. that can all be treated in the same way. The chlorinated hydrocarbons can be taken as another example.
Retention data
for the n-chloroalkanes taken over a temperature range of 76˚C to
88˚C on a n-C30 alkane stationary phase can also be examined
thermodynamically. Employing the same procedure Log(V'r(T)) for the
solutes n-chlorobutane, n-chloropentane, n-chlorohexane
and n-chloroheptane were plotted against the number of methylene groups
at each temperature. The slope (representing the methylene contribution (
),
the intercept for the methyl group (
) (taken from data for
the n-alkane series which was also available on the same stationary
phase and temperature range), and the intercept due to the interaction with the
chlorine atom,
(taken as the difference between
the actual intercept and that of the methyl group) were each plotted against
the reciprocal of the absolute temperature.and the results are shown in figure
10.
 
