A current is passed through a molten mixture of ZnI₂ and KCl. Given the half reactions shown below, the product at the cathode is:
K⁺ + e^-→K E ° = - 2.92 V Zn²⁺ + 2 e^-→Zn E ° = - 0.76 V I₂ + 2 e^-→2 I^- E ° = +0.535 V Cl₂ + 2 e^-→2 Cl^- E ° = +1.36 V

Question

Quizplus · Accepted Answer

The product at the cathode is determined by the reduction potential (E°) of the half-reactions. The more positive the E°, the more likely the reduction will occur at the cathode. However, in electrolysis, the substance with the least positive (or most negative) E° is reduced at the cathode. Among the given options, Zn has the least negative E° value (-0.76 V) compared to K (-2.92 V), making Zn the product at the cathode.

A Current Is Passed Through a Molten Mixture of ZnI2

A Current Is Passed Through a Molten Mixture of ZnI₂