Non-ideality and ion-pairing in saturated aqueous solution of sodium fluoride at 25 °C

✍ Scribed by M. Aghaie; E. Samaie

• Publisher: Elsevier Science
• Year: 2006
• Tongue: English
• Weight: 96 KB
• Volume: 126
• Category: Article
• ISSN: 0167-7322
• DOI: 10.1016/j.molliq.2005.09.007

✦ Synopsis

Using Solvent Evaporating and Atomic Emission Spectrophotometric methods, the solubility of NaF in water at 25 °C was determined. Comparing the value of the thermodynamic solubility product constant, K sp(th) , (K sp(th) = exp(-ΔG diss °/RT)) of NaF to the value which is obtained from the observed solubility, s/mol L -1 , and activity coefficients, f + and f -, which are estimated upon the extended Debye-Hückel law,

revealed a great difference. The difference has satisfactorily been explained using a combination of Debye-Hückel law and Ion-Association Theory.