Thermodynamics of Transfer of Hydrogen Ion from Water to Dioxane-Water Mixtures
| Main Authors: | (MRs.) K. MAJUMDAR (nee SENGUPTA), S. C. LAHIRI, D. C. MUKHERJEE |
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| Format: | Article Journal |
| Bahasa: | eng |
| Terbitan: |
, 1993
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| Subjects: | |
| Online Access: |
https://zenodo.org/record/5939694 |
Daftar Isi:
- Department of Chemistry, University of Kalyani, Kalyani-741 235 Department of Pure Chemistry, University College of Science & Technology, 92 Acharya Prafulla Chandra Road,Calcutta-700 009 Manuscript received 29 January 1993 The thermodynamic dissociation constants for the isoelectric reaction LH+ \(\rightleftharpoons\) L + H+ (where L = 1,10-phenanthroline)have been determined pH-metrically and spectrophotometrically in dioxane + water (D + H2O) mixtures (0-90 wt% of dioxane). The data were utilised to calculate the free energies of transfer of 11' ion from water to dioxane+ water mixtures. Enthalpies and entropies of transfer of 1-1' ion (in 0-60 wt% of D) have also been determined using the calorimetric data of earlier experiments in a similar way. The changes in the pK values and the thermodynamics of transfer of H ion have been interpreted in terms of solvent basicity and ion-solvent interactions. The thermodynamics of transfer of H+ ion suggests that D + H2O mixtures are more basic than water. The basicity increases and passes through a maximum in the region 45-50 wt% of D and ultimately above 80 wt% of D (D : H2O:~ 1); the binary mixtures are less basic than water. It appears that D is less basic than water in the, liquid state. The results are consistent with the structural changes associated with the addition of a solvent D to water.