Autoprotolysis constants of ethylene glycol in isodielectric mixtures of ethylene glycol and N, N-dimethyl formamide at 298.15 K and the related Gibbs energies of transfer
2007
Autoprotolysis constants (K s ) of ethylene glycol (EgOH) have been determined in the isodielectric mixtures of protic ethylene glycol and dipolar aprotic N,N-dimethyl formamide (20, 40 and 60 wt% DMF) at 298.15 K from emf measurements of cells comprising glass GE (H + ) and Ag-AgCl electrodes. Transfer Gibbs energies of glycoxide ion (EgO ), ΔG 0 t (EgO - ) have been evaluated therefrom using literature values of transfer Gibbs energies of H + , ΔG 0 t (H + ) based on TATB assumption. These are explained in the light of ion-solvent interactions as guided by physicochemical properties of the solvents. The results show that while the acidity of EgOH + DMF mixed solvents decreases with co-solvent due to the increased aproticity and anionophobicity of the cosolvent molecules, the basicity decreases due to the amalgamated effects of increased aproticity as well as increased protophilicity of DMF.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
2
References
4
Citations
NaN
KQI