ISSN:
1572-8927
Keywords:
enthalpy of solution
;
enthalpy of cavity formation
;
enthalpy of interaction
;
aliphatic ester
;
1,2-dichloroethane
;
n-hexane
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract Calorimetric measurements were carried out on ester-solvent systems where the esters were H(CH2)xCOO(CH2)yH, with x and y varying from 1 to 5, and the solvents were n-hexane and 1,2-dichloroethane. Calculation of the enthalpies of cavity formation enabled the enthalpies of interaction to be determined. Both enthalpies correlated with number of carbon atoms N, equal to x+y in the esters, giving for 1,2-dichloroethane $$\begin{gathered} \Delta _{cav} H_m^O = 29.4 \pm 2.3 + 4.7 \pm 0.4N \hfill \\ \Delta _{int} H_m^O = - 53.9 \pm 2.5 - 8.2 \pm 0.5N \hfill \\ \end{gathered} $$ and for n-hexane $$\begin{gathered} \Delta _{cav} H_m^O = 8.8 \pm 1.1 + 3.4 \pm 0.2N \hfill \\ \Delta _{int} H_m^O = - 20.0 \pm 2.1 - 8.3 \pm 0.4N \hfill \\ \end{gathered} $$ From these linear correlations enthalpies of an aliphatic ester, for example, the enthalpy of vaporization can be calculated by using a thermochemical cycle. The presence of chloro atoms in the aliphatic solvent causes a large interactive effect between the ester and 1,2-dichloroethane.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00973048
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