Reference Electrodes
Junction Potential
Glass Electrodes and pH Measurements
Understanding Junction Potentials

Concept #1: Differences in ion concentrations and ion mobility help to create junction potentials at each end of a salt bridge. 

Mobility of ions is based on their size and the greater the difference in sizes between the two ions the greater the potential.

Example #1: Determine the electrical potential that results from the given galvanic cell. Assume that the junction potential is minimal.