Date of Award


Degree Type


Degree Name

Master of Science (MS)

Author's Department


First Advisor

David W. Ebdon


A new method for determining ion association constants in aqueous solutions using ion selective electrodes has been developed. This method has been applied to the NaCO3-, NaSO4- and KCO3- ion pairs at 25°C. Association constants for NaCO3- and NaSO4- were determined at various ionic strengths and extrapolated to zero ionic strength to yield 2.2 ± 0.2 for NaCO3- and 5.3 ± 0.4 for NaSO4-. Values for the association constants at an ionic strength near sea water (I=0.70) were calculated to be 1.7 ± 0.1 for NaCO3- and 2.1 ± 0.2 for NaSO4-. The KCO3- association constant was determined to be between zero and one.

Other less direct methods of determining these constants were tested and evaluated. It was also evident sodium m-benzenedisulfonate is a weakly associated electrolyte, which may associate to approximately the same extent as sodium carbonate. An Orion model 94-11 Sodium Ion Electrode, Orion model 93-19 Potassium Ion Electrode, Sensorex model S810C03 Carbonate Sensitive Electrode and Chemtrix model 1015M Sulfate Electrode were used and compared in this study.

Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Included in

Chemistry Commons