Increasing which concentration would likely raise the e.m.f of the cell involving H2 and Ag?

To understand why increasing the concentration of H+(aq) would likely raise the electromotive force (e.m.f) of the cell involving H2 and Ag, it's essential to consider the Nernst equation, which describes how the e.m.f of an electrochemical cell changes with concentration levels of the reactants and products.

In the case of a hydrogen electrode, which involves H2 and H+, increasing the concentration of H+ ions shifts the equilibrium toward the reduction of hydrogen ions to hydrogen gas. Since the standard cell potential for the hydrogen half-reaction is set as a reference point (0 volts), any increase in H+ concentration will favor the forward reaction, thus elevating the potential at which this half-cell operates. This, in turn, increases the overall e.m.f of the cell.

For the silver electrode, increasing the concentration of Ag+ may influence the cell potential as well, but it does not have the same direct impact on e.m.f as the H+ concentration does in this specific cell. The silver ion reduction is less responsive to changes in concentration compared to the hydrogen half-reaction, particularly when considering standard conditions.

In summary, by increasing the concentration of H+(aq), the reaction equilibrium shifts favorably, increasing the cell