Thermodynamic properties of (an ester+an alkane). XVIII. Experimental values for (an alkyl butanoate+an alkane) at T=318.15K

Thermodynamic study of (alkyl esters+α,ω-alkyl dihalides) VI. and for 20 binary mixtures {xCu−1H2u−1CO2(CH2)3CH3+(1−x)α,ω-BrCH2(CH2)v−2CH2Br}, where u=1 to 5, α=1, and v=ω=2 to 6

“…However, the estimate made using only one pair of values for propanoates and butanoates, C uÀ1 H 2uÀ1 COO(CH 2 ) 3 CH 3 (u = 3, 4), is not adequate. This was also confirmed for the systems studied previously for ethyl [1] and methyl alkanoates [2].…”

“…At least from a qualitative perspective, the existence of opposing effects, exo/ endothermic in the H E m and expansion/contraction in the V E m , are the result of different interactional contributions mentioned previously, and clearly vary in relation to the chain length of the compounds constituting the binary mixture, as explained below. In general, the behaviour of these mixtures is as expected from the results obtained in the series of papers [1,2,5,9,10], in which they have been discussed to some length. For this reason, here we only mention the effects that are specific to this type of mixture.…”

“…As indicated in previous works [1,2], in the correlation of ðx 1 ; V E m Þ, the parameter k identifies with k v ¼ V m;2 =V m;1 , where V m;i ¼ uðTÞ the volume of the pure compound i, which is temperature-dependent. However, in the correlation of the points ðx 1 ; H E m Þ, if it is assumed that the interaction energies are directly related to the contact surfaces of the molecules, the parameter k identifies with k h ¼ S 2 =S 1 , which can be estimated from the following expression:…”

“…The graphs corresponding to the presentation of experimental and correlation data of H the values of ðV E m to x ¼ 0:5Þ of the mixtures in this work are compared with those corresponding to the methyl esters [2], showing the irregular sequence as a function of the hydrocarbon chain of the two compounds involved in the mixture. This can also be explained by the existence of several of the effects we mention.…”

“…In this work, we present data for enthalpies H E m and volumes V E m for a group of twenty mixtures of butyl alkanoates (metanoate to butanoate) with five a,x-dibromoalkanes (a = 1, x = 2 to 6) at a temperature of 298.15 K. Experimental data are provided for these binary systems for which no data had been previously published in the literature, in order to expand on the data obtained in previous works for similar mixtures with ethyl [1] and methyl alkanoates [2]. All this information will help to explain the behaviour and the specific interactions of dihalide mixtures.…”