redn potential of hydrogen electrode = pH × -0.059 so, pH = 10 & pOH =4 Hence hydroxide ion concentration = 10^-4

Introduction

In electrochemistry, the potential of hydrogen (pH) electrode is used to measure the acidity or alkalinity of a solution. The pH electrode measures the difference in potential between a reference electrode and a pH-sensitive electrode.

Explanation

If the potential of hydrogen electrode in contact with a solution is nearly -0.6 V, then the hydroxide ion concentration of the solution can be calculated using the Nernst equation:

E = E° - (RT/nF) ln([OH^-])

where E is the measured potential of the pH electrode, E° is the standard potential of the hydrogen electrode (0 V), R is the gas constant, T is the temperature, n is the number of electrons transferred in the reaction, F is the Faraday constant, and [OH^-] is the hydroxide ion concentration of the solution.

Solving for [OH^-], we get:

[OH^-] = 10^(-(E - E°)/(RT/nF))

Substituting the given values, we get:

[OH^-] = 10^(-(0.6 - 0)/(8.3145*298/1*96485))

[OH^-] = 1.0 x 10^-14 M

This is the hydroxide ion concentration of a neutral solution at 25°C. Therefore, the solution in contact with the pH electrode is neutral.

Conclusion

In conclusion, if the potential of hydrogen electrode in contact with a solution is nearly -0.6 V, the hydroxide ion concentration of the solution can be calculated using the Nernst equation. In this case, the solution is neutral.