Galvanic & Electrolytic Cell Simulator

Electrodes

Left electrode (metal A)

Right electrode (metal B)

[Mⁿ⁺] left 0.50 M

[Mⁿ⁺] right 0.50 M

Cell mode

Applied external voltage -1.00 V

Only active in Electrolysis — an external source can force current the "wrong" way, even reversing a spontaneous cell.

Time scale 1.0x

Live readout

E°cell (standard)

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E cell (Nernst)

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Reaction quotient Q

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ΔG (kJ/mol)

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Current (relative)

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Spontaneous?

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How this model works

Each beaker holds a metal rod in a solution of its own cation. A wire above carries electrons between the two rods; a salt bridge below lets ions migrate to keep both sides electrically neutral. The rod that loses electrons (oxidises) is the anode and slowly dissolves — its ion count rises and the rod visibly shortens. The rod that gains electrons (reduces) is the cathode, plates out fresh metal, and grows.

E°cell = E°(right) − E°(left)
E = E°cell − (0.0592/n)·log10(Q),  Q = [M(left)ⁿ⁺] / [M(right)ⁿ⁺]
ΔG = −nFE   (F = 96485 C/mol)

In Galvanic mode the reaction runs on its own thermodynamic driving force, E: positive E means the left rod oxidises and electrons flow left→right; negative E reverses it automatically — pick two electrodes any way you like and the current still finds the true spontaneous direction.

In Electrolysis mode an external source adds a voltage to the cell (netDriving = E + V_applied). Enough applied voltage in the right direction can force the non-spontaneous reaction to run anyway — this is exactly how electroplating and industrial refining defeat an unfavourable E°.

[Mⁿ⁺] — cation concentration in each beaker; changing it shifts Q and therefore E, per the Nernst equation.
Applied voltage — the external EMF in electrolysis mode; its sign sets which side is forced to oxidise.
Time scale — speeds up or slows down the whole animation, including electron/ion drift and electrode growth.

Simplification: every half-reaction is modelled as an n=2 electron transfer for a consistent Nernst slope (silver is properly n=1) — a deliberate teaching simplification, not a literal balanced equation.

GALVANIC

Electron (wire) Cation (bridge) Anion (bridge)

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