Details

Autor(en) / Beteiligte

• Arce, Alberto
• Wilczek-Vera, Grazyna
• Vera, Juan H.

Titel

Activities of aqueous Na + and Cl - ions from homoionic measurements with null junction potentials at different concentrations

Ist Teil von

• Chemical engineering science, 2007-07, Vol.62 (14), p.3849-3857

Ort / Verlag

Oxford: Elsevier Ltd

Erscheinungsjahr

2007

Quelle

Elsevier ScienceDirect Journals

Beschreibungen/Notizen

• Individual Na + and Cl - ionic activity coefficients were measured in aqueous solutions of NaCl at 298.15 K in a homoionic system. The emf of sodium and chloride half-cell ion-selective electrodes (ISEs) was measured against a single junction reference electrode of Ag/AgCl, filled with NaCl solutions. Experimental runs were performed at concentrations 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 m of the filling solution. In each run, the concentration of the sample solution was increased from around 1 × 10 - 3 m , up to the corresponding molality of the filling solution. Thus, the last point of each run had a zero liquid-junction potential. The ionic activity coefficients measured in this work were found to be independent of the molal concentration of the filling solution used and in good agreement with previous results obtained using heteroionic systems.