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The experimental values of absolute viscosity in N,N-dimethylformamide + ethanol binary fluid mixtures (from 303.15 to 323.15 K) can induce us to investigate different correlation expressions as well as their derivative quantities. Investigation of the molar enthalpy of viscous flow (∆H*) and the viscosity activation energy (Ea) reveals close values and similar variation against composition, here we can justify the notion of partial activation energies Ea1 and Ea2 for pure components along with their separately individual contributions. Correlation between the two Arrhenius parameters in the whole range of compositions shows the existence of different interaction behaviours, delimited by peculiar compositions. It is also noticed that the ratio between the two parameters leads to the Arrhenius temperature which is in causal correlation with the temperature of vapourization in the liquid-vapour isobaric diagram and the limiting partial properties can permit us to predict values of the boiling temperatures of the pure fluid components.

Calculation of excess properties in N,N-dimethylacetamide + 2-methoxyethanol binary mixtures at (298.15, 308.15 and 318.15) K from experimental density, viscosity and sound velocity values were presented in previous work. Applications of these experimental values to test different correlation equations as well as their corresponding relative functions were also reported. Considering the quasi-equality between the Arrhenius activation energy Ea and the enthalpy of activation of viscous flow ΔH*, here we can define partial molar activation energy Ea 1 and Ea 2 for N,N-dimethylacetamide and 2-methoxyethanol, respectively, along with their individual contribution separately. Correlation between Arrhenius parameters reveals interesting Arrhenius temperature with a comparison to the vaporisation temperature in the liquid vapour equilibrium, and the limiting corresponding partial molar properties that can permit us to estimate the boiling points of the pure components.

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