Excess Molar Volumes of Binary Mixtures of an Isomer of Pentanol +N-Methyl Morpholine an Interpretation in Terms of the Prigogine-Flory- Patterson Theory

Abstract

The results of measurements of excess molar volumes VE at 298.15 K over
the whole mole fraction range for five mixtures (N-methylmorpholine + 2-pentanol;
+ 3-pentanol;+ 3-methyl-1-butanol; + 2-methyl-1-butanol; and 2-methyl-2-butanol)
are presented. The experimental values of VE show a negative deviation from ideal
for the five sets of binary mixtures in except VE values for mixtures of (Nmethylmorpholine
+ 2-pentanol; and 3-pentanol) showes two structural regions. The
first is positive at mole fraction 0 X2 0.25. The second region is negative at mole
fraction 0.25 X2 1. The negativity of VE increases in the order 2-methyl-2-butanol
> 2-methyl-1-butanol > 3-methyl-1-butanol > 3-pentanol > 2-pentanol. The
experimental results of VE are compared with those predicted by the Prigogine-
Flory- Petterson theory . The theory poorly predicts the experimental VE. The
experimental value of excess molar volumes VE were fitted to the Redlich- Kister
polynomial equation to derive the binary adjustable parameters and the standard
deviations.
The results obtained are used to study the nature of molecular interactions in
these mixtures. As far as we know, in the open literature, no study on mixtures
containing N-methylmorpholine