How does electrolysis convert electrical energy into chemical energy?
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Electrolysis is a process that converts electrical energy into chemical energy by passing an electric current through a substance to induce a chemical change. This process occurs within an electrolytic cell, which consists of two electrodes submerged in an electrolyte—a solution or molten compound containing charged ions.12
When an external electrical potential is applied, the electrodes become oppositely charged. This forces the ions in the electrolyte to migrate toward the electrode of opposite polarity:
* At the cathode (negative electrode): Positive ions migrate to the cathode, where they gain electrons (a process called reduction) to become neutral atoms or new molecules.123
* At the anode (positive electrode): Negative ions migrate to the anode, where they transfer electrons to the electrode (a process called oxidation) to become neutral particles or new molecules.123
The energy supplied by the electric current drives these non-spontaneous chemical reactions, effectively storing the electrical energy as chemical potential energy within the resulting products.2