Chemistry - Electrochemistry Question with Solution | TestHub

Explain the question: Conditions for increasing $E_{Ag/AgCl}$.

Concept: Nernst Equation dependence on $\left[C{l}^{-}\right]$

Solution: The electrode potential for the ${}_{Ag/AgCl}$ system is determined by the Nernst equation:

$$E=E^{\circ }-0.059\log [C{l}^{-}]$$

This equation shows that the potential $E$ is inversely related to the concentration of chloride ions.

Option (A): Decreasing $[C{l}^{-}]$ reduces the value of the logarithmic term being subtracted from $E^{\circ }$, thereby increasing the overall potential $E$.

Option (C): Adding $AgN{O}_3$ introduces $A{g}^{+}$ ions which react with $C{l}^{-}$ to form $AgCl$ precipitate. This chemical reaction decreases the concentration of $C{l}^{-}$ in the solution. As established in Option (A), a decrease in $[C{l}^{-}]$ leads to an increase in the electrode potential.

Option (D): Surface area is an extensive property and does not affect the intensive property of electrode potential.

Option (B): Temperature changes typically decrease the potential of this specific electrode relative to SHE.

Final Answer: Option (A) and (C)