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⚡ Applied Potential and Electron Flow Visualiser

Visualise how changing the applied potential relative to the equilibrium potential drives electron transfer in the Zn/Zn²⁺ redox system.

More Negative
(-1.36 V)
More Positive
(-0.16 V)
-0.76 V

0.00 V

Energy Level Diagram

Reaction Information

Zn ⇌ Zn²⁺ + 2e⁻

🔴 Fermi Level Position

At equilibrium

⚡ Dominant Reaction

Equal forward and reverse rates

Current:
0.00 mA/cm²

🔬 What's Happening

Dynamic equilibrium: oxidation and reduction rates are equal

🎓 Understanding the Relationship

🔑 Key Concept: Applied potential controls the energy of electrons in the electrode (Fermi level).

⬆️ More Negative Potential (E ↓): RAISES electron energy (Fermi level ↑) → Makes electrons harder to remove → Reduction favored → Zn²⁺ gains electrons

⬇️ More Positive Potential (E ↑): LOWERS electron energy (Fermi level ↓) → Makes electrons easier to remove → Oxidation favored → Zn loses electrons

⚖️ At Equilibrium (E = E°): Fermi level aligns with redox couple → Forward and reverse rates equal → No net current

⚡ Exponential Rate: Electron transfer rate increases exponentially with overpotential (Butler-Volmer kinetics) - small changes in η produce large changes in current!

💡 Remember: Electrons flow from high energy to low energy. The applied potential adjusts whether the electrode is "uphill" or "downhill" relative to the solution!