Question

The Zn/Zn2+ electrode has a standard electrode potential of E° = −0.76 V. How does the relative potential energy of an electron at the Zn/Zn2+ electrode compare to the potential energy of an electron at the standard hydrogen electrode?

Answer 1

Relative to the standard hydrogen electrode (SHE), the potential energy of an electron at the Zn/Zn2+ electrode is higher, due to its standard electrode potential being -0.76 V, while the SHE is defined as 0 V.

Step-by-step explanation:

The standard electrode potential of the Zn/Zn2+ electrode is E° = −0.76 V. When comparing to the standard hydrogen electrode (SHE), which has a potential of 0 V, the electrons at the Zn/Zn2+ electrode have higher potential energy.

This is because electrons flow from an area of higher to lower potential energy, and the negative sign of the Zn/Zn2+ electrode's potential suggests that it is more negative relative to the SHE.

The standard reduction potential for the hydrogen electrode is defined as exactly 0 V. Considering this, since the standard reduction potential of the Zn2+ is −0.76 V, the electrons at the Zn/Zn2+ electrode have higher potential energy in relative terms compared to the SHE, which is acting as the cathode in this scenario. The Zn/Zn2+ electrode thus serves as the anode, where oxidation occurs and electrons are released.