Density and Volumic Properties of N,N-Dimethylformamide + 2-Methoxyethanol + 1,2-Dimethoxyethane Liquid Ternary Mixtures

Abstract

Densities (ρ) at various temperatures ranging from −10 up to +80 °C have been measured for N,N-dimethylformamide + 2-methoxyethanol + 1,2-dimethoxyethane ternary solvent system, employing 66 mixtures covering the whole miscibility field. Polynomial equations describing the dependence on temperature, ρ = ρ(t/°C), and molar composition, ρ = ρ(X1,X2), have been checked. Furthermore, the excess molar volumes (VE), derived from ρ values, can provide useful suggestions about the formation of solvent–cosolvent complexes. Excess molar volumes have been interpreted on the basis of specific interactions between unlike molecules, taking into account geometric effects and steric hindrances. The VE quantities have been isothermally fitted by an empirical relation of the type VE = VE(X1,X2,X3) formally derived from the well known Redlich–Kister equation. As a rule, for all the here tested relationships, the calculated values agree very well with the experimental ones, indicating that all the equations can be safely employed for predictive calculations in correspondence of the experimental data gaps.

Volumetric properties of binary mixtures of alkoxyethanols with ethyl tert-butyl ether at various temperatures

“…In all studied mixtures, the large negative values of V E are the result of contributions of several factors [12][13][14][15].…”

“…Many investigations of the density behaviour of liquids have been reported in the literature and the best representation of the results as a function of temperature is given by the following equation [12]:…”

“…The values of Dq ¼ AE1:7 Á 10 À5 g Á cm À3 for (ETBE + ME), Dq ¼ AE2:5 Á 10 À5 g Á cm À3 for (ETBE + DEM) and The variation of the density with binary composition was studied by using the following equation [12]:…”

Excess molar volumes of the binary mixtures of polyethylene glycol 300 with ethoxyethanols at various temperatures

“…Many investigations of the density behaviour of liquids have been reported in the literature and the best representation of the results as a function of temperature is given by the following equation [13]:…”

A Study of the Dielectric Behaviour and the Liquid Structure of a Ternary Solvent System

“…where V is the apparent molar volume of the real system at each experimental condition, 4 and ε ∞ is the limiting high-frequency permittivity of the medium. When dealing with polar species, it is common practice to choose ε ∞ ≅ 1.1 n D 2 (n D = refractive index at the Na D-line), in view of the experimental difficulties to measure the dielectric constant in the IR frequency region.…”