Chemistry Regents Practice Test 2025 – Complete Prep Resource

In an electrochemical cell, oxidation and reduction reactions are key processes that allow the cell to generate electrical energy. Oxidation is defined as the loss of electrons, while reduction is defined as the gain of electrons.

In this context, the anode is the electrode where oxidation takes place. At the anode, a substance loses electrons, which increases its oxidation state. These electrons then flow through the external circuit to the cathode.

On the other hand, the cathode is where reduction occurs. At the cathode, a substance gains the electrons that have traveled through the external circuit, resulting in a decrease in its oxidation state.

Therefore, in an operating electrochemical cell, oxidation occurs at the anode and reduction occurs at the cathode. This principle is essential for understanding the functioning of electrochemical cells, such as batteries and electrolytic cells, and highlights the importance of the flow of electrons between the two electrodes.