Thermodynamics of the solvation of non-electrolytes in C8 monofunctional organic solvents

Some results are reported concerning the enthalpies of solvation (Delta H-s olv(o)) of some hydrocarbons (hexane, cyclohexane), ethers (tetrahydrofuran ), ketones (cyclopentanone, pentan-3-one), alcohols (butan-1-ol. butan-2-ol ). and water in octan-2-ol and hexylacetate. The Delta H-solv(o) values wer e calculated by combining the calorimetric heats of solution here determine d with the known enthalpies of vaporisation. In the investigated solvents, the enthalpies of solvation become less negat ive going from alcohols to ketones to ethers and to hydrocarbons. As regard s alcohols and ketones, the Delta H-solv(o) values are more differentiated in octan-2-ol than in hexylacetate. This reflects the different nature of t he two solvents, amphiprotic the former and hydrogen bond acceptor the latt er. The results are interpreted in terms of specific solute-solvent interac tions. (C) 2001 Elsevier Science B.V. All rights reserved.