What is the approximate pH of the H⁺(aq)/H₂(g)electrode compartment through which H₂ gas is bubbled at a pressure of 1.00 atm if this electrode,when coupled with a Ni(s)/(0.10 M)Ni²⁺(aq)electrode,forms a galvanic cell having an initial potential of 0.10 V? [The discharge reaction involves oxidation of nickel to Ni²⁺(aq).] A)2.15 B)4.65 C)6.15 D)3.15 E)3.65

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Quizplus · Accepted Answer

The potential of the cell is given by the Nernst equation. The standard potential for the Ni/Ni²⁺ couple is -0.25 V. The cell potential is 0.10 V, so the potential of the H⁺/H₂ electrode is 0.10 V - (-0.25 V) = 0.35 V. Using the Nernst equation for the hydrogen electrode, E = 0 - (0.0591/1)log[H⁺], we find that log[H⁺] = -0.35/0.0591, which gives a pH of approximately 3.15.

What Is the Approximate PH of the H+(aq)/H2(g)electrode Compartment Through

What Is the Approximate PH of the H⁺(aq)/H₂(g)electrode Compartment Through