Which factor is responsible for the production of electricity in an Electrochemical cell?

Redox reaction

The correct answer is: 3. Redox reaction

The production of electricity in an electrochemical cell is based on a redox (reduction-oxidation) reaction. In a redox reaction, one species undergoes oxidation (loses electrons) while another species undergoes reduction (gains electrons). This transfer of electrons between the reactants results in the generation of electrical energy.

An electrochemical cell consists of two half-cells, where each half-cell contains an electrode immersed in an electrolyte. In one half-cell, the oxidation half-reaction takes place, where a species loses electrons and is oxidized. These electrons are released into the external circuit through the electrode. In the other half-cell, the reduction half-reaction takes place, where another species gains electrons and is reduced. These electrons are received from the external circuit through the electrode.

The flow of electrons through the external circuit, from the anode (where oxidation occurs) to the cathode (where reduction occurs), creates an electric current, leading to the production of electricity in the electrochemical cell.

Therefore, the correct answer is option 3. Redox reaction.