Question

A nitrate electrode responds to nitrate ion concentration according to the equation below. If the net voltage is -0.100 volts in 0.01000 M KNO3 against the saturated calomel electrode (E = 0.241 V). what would be the potential against the silver/silver chloride reference electrode

(E = 0.197 V) ? Enter your answer below, to three digits after the decimal point. Do not enter units or any spaces.

E = constant - (0.05916) log [NO3-]

Answer 1

The Nernst equation, which depicts the voltage that develops at this nitrate electrode is given by the following equation:

E = constant - (0.05916) log [NO3-]

The concentration of nitrate ion is given to us as:

[NO3-] = 0.01 M

Net voltage generated by this electrode against saturated calomel electrode is given as -0.1 V

So, the absolute emf value for this nitrate electrode is calculated using following relation:

Enitrate - Ecalomel = -0.1

Enitrate = Ecalomel - 0.1 = 0.241-0.1 = 0.141 V

Now, then we set up this nitrate electrode against a silver chloride electrode, the net potential that would be developed is:

Enetpotential = Enitrate - Esilverchloride = 0.141-0.197 = -0.056 V