RT info:eu-repo/semantics/article
T1 Thermodynamics of amide + ketone mixtures. 2. Volumetric, speed of sound and refractive index data for N,N-dimethylacetamide + 2-alkanone systems at several temperatures. Application of Flory's model to tertiary amide +n-alkanone systems
A1 Cobos Huerga, Ana
A1 González López, Juan Antonio Mariano
A1 Hevia de los Mozos, Luis Fernando
A1 García de la Fuente, Isaías Laudelino
A1 Alonso-Tristán, Cristina
K1 Termodinámica
K1 2213 Termodinámica
AB Data on density, rho, speed of sound, c, and refractive index, nD, have been reported at (293–303.15) K for the N,Ndimethylacetamide (DMA) + CH3CO(CH2)_(u – 1)CH3 (u = 1, 2, 3) systems, and at 298.15 K for the mixture with u=5. These data have been used to compute excessmolar volumes, VmE, excess adiabatic compressibilities, kSE, and excess speeds of sound cE. Negative VmE values indicate the existence of structural effects and interactions between unlike molecules. From molar excess enthalpies, HmE, available in the literature for N,N-dimethylformamide (DMF), or N-methylpyrrolidone (NMP) + n-alkanone systems, it is shown: (i) amide-ketone interactions are stronger in DMF systems than in those with NMP; (ii) they become weaker when u increases in mixtures with a given amide. Structural effects largely contribute to HmE and are more relevant in mixtures containing NMP. The application of the Flory's model reveals that the random mixing hypothesis is valid in large extent for DMF solutions, while NMP systems are characterized by rather strong orientational effects. From values of molar refraction and of the product PintVm (where Pint is the internal pressure and Vm the molar volume), it is concluded that dispersive interactions increase with u, or when DMF is replaced by DMA in mixtures with a fixed ketone.
PB Elsevier
SN 0167-7322
YR 2017
FD 2017
LK https://uvadoc.uva.es/handle/10324/69149
UL https://uvadoc.uva.es/handle/10324/69149
LA spa
NO Journal of Molecular Liquids, 2017, 248, 286-301
DS UVaDOC
RD 01-sep-2024