Volumetric behaviour and isentropic compressibility of formamide with 2-dialkylaminoethanols

The volumetric properties and isentropic compressibilities of binary mixtures of formamide (FA) with 2-dialkylaminoethanols viz. 2-dimethylaminoethanol (2-DMAE) and 2-diethylaminoethanol (2-DEAE) were evaluated over the entire composition range at 303.15, 313.15 and 323.15 K and at atmospheric pressure. The excess partial molar volumes (V¯m,1E and V¯m,2E), excess isentropic compressibility (κsE), excess partial molar compressions (K¯s,m,1E and K¯s,m,2E) are deduced. The partial molar volumes (V¯m,1∘ and V¯m,2∘), partial molar compressions (K¯s,m,1∘ and K¯s,m,2∘), excess partial molar volumes (V¯m,1∘E and V¯m,2∘E), and excess partial molar compressions (K¯s,m,1∘E and K¯s,m,2∘E), at infinite dilution, over the entire composition range are also calculated. The knowledge of the volumetric properties and molar compression aids to understand specific molecular interactions existing between the FA and 2-DMAE/2-DEAE molecules of the binary system. The strength of intermolecular interactions in these mixtures follows the order: FA + 2-DEAE > FA + 2-DMAE. The required experimental data are used from our earlier work on the volumetric and acoustic study published in J. Mol. Liqs. 219 186 (2016).