Question

In fluoride ion electrode, the potential corresponding to level of the fluoride ion is described by which of the following equations when E is the measured electrode potential, Eo is the reference potential and A is the level of fluoride ions in solution?

(a) E=Eo+0.0591 log A

(b) E=Eo-0.0591 log A

(c) E=Eo+0.0896 log A

(d) E=Eo-0.0896 log A

This question was posed to me in an online quiz.

My question is from Ammonia and Fluoride Electrode in division pH Meters and Ion Analysers of Analytical Instrumentation

Answer 1

The correct answer is (b) E=Eo-0.0591 log A

Easiest explanation: In fluoride ion electrode, the potential corresponding to level of the fluoride ion is described by the equation, E=Eo-0.0591 log A. A is the activity or effective concentration of fluoride ions.