the ion-pair association constant values, related to the reaction +  were determined by means of the nmr spectroscopy. the values of the thermodynamic functions of the ion pairing process were calculated on the basis of the nmr results. in addition, the association entropy was found to be dependent on the temperature. comparing the experimental data and the fuoss theory it is found that  ion-pa...

using the mixed solvents, (water +ethanol + propanol), the solubility of cdf2 was determined byevaporating method at 25° c. the results showed that the sollbility, s, of cdf2 decreases bydecreasing the dielectric constant of the mixed solvent .once the solubility of cdf2 was determined,the concentration solubility product, ksp(c)=4s3, was calculated .furthermore ,by estimating the meanactivity ...

in the present study, a simple and sensitive extractive spectrophotometric method is described for determination of buspirone. the method is based on the reaction of buspirone and bromocresol green. the ion-pair complex was quantitatively extracted into chloroform at ph 2.3 followed by spectrophotometric determination at 415 nm. the complex was stable up to 2 days and obeyed beer's law over the...

a simple and sensitive extractive spectrophotometric method is described for determination of tropicamide. the method is based on the reaction of tropicamide and bromocresol green. the ion-paired colored complex was extracted with chloroform at ph 3. the extracted complex showed maximum absorbance at 423 nm. the complex was stable up to 2 days and obeyed beer's law over the concentration r...

using solvent evaporating and atomic emission spectrophotometric methods, the solubility of li2co3 in waterat 25°c was determined. comparing the value of thermodynamic solubility product constant, ksp(th),(ksp(tn) = exp(—ag.ss/rt)) of the mentioned salt to the value which is obtained from the observed solubility,shnoll-1 , and activity coefficients, f+ and f, which are estimated upon the extend...

in this study a sensitive, simple and accurate spectrophotometric method was suggested for determination of tamsulosin in bulk powder and pharmaceutical dosage form based on the formation of an ion-pair complex between the drug and bromocresol green in a buffer solution at ph 3.5. the formed yellow color complex was extracted with chloroform and measured at 415 nm. the optimum reaction conditio...

in this study, the ion association phenomenon in the saturated solution of kcl in the mixed solvent(methanol+water) was studied. the solubility of this compound in the mixed solvent (methanol+water by value percent of methanol = 60%), and in the presence of various molarities of nano3 wasdetermined by the solvent evaporation method at 25.0°c. the results enable us to estimate the valueof thermo...

using the evaporating method, the solubility of potassium nitrate was determined in various mixtures containing water and ethanol at 25°c. the results show that the solubility of kno3 decreases with increasing the mass percent of ethanol in the mixtures. this trend is along with decreasing the dielectric constant of water+ethanol mixtures. moreover, it can be concluded that the totqal solubilit...

The ion-pair association constant values, related to the reaction +  were determined by means of the NMR spectroscopy. The values of the thermodynamic functions of the ion pairing process were calculated on the basis of the NMR results. In addition, the association entropy was found to be dependent on the temperature. Comparing the experimental data and the Fuoss theory it is found that  ion-pa...