CBSE Class 12 · 2000 · Delhi Compartment · Redox Reactions and ElectrochemistryVery Short Answer

What is the effect of increase in concentration of zinc ions on the electrode potential of zinc electrode, for which

E_{Z n^{2 +} /Zn}^{\circ} = - 0.76

Answer: The (reduction) electrode potential increases (becomes less negative).

Solution

By the Nernst equation for the electrode Zn

^{2 +}

+ 2e

^{-} \to

Zn:

E = E^{\circ} + \frac{0.059}{2} lo g [Z n^{2 +}]

An increase in [Zn

^{2 +}

] increases the log term, so the electrode potential increases (becomes less negative than −0.76 V).

CBSE Class 12 Board · 2000 · Delhi Compartment · Subjective