Which electrode is referred to as the cathode in an electrolytic cell?

In an electrolytic cell, the cathode is defined as the electrode where reduction occurs. This is the site where electrons are gained by species in solution, leading to a decrease in oxidation state. The cathode is assigned a negative charge because it serves as the source of electrons that flow through the external circuit, allowing reduction reactions to take place at its surface.

Understanding the role of the cathode is crucial, as it directly affects the chemical reactions occurring within the cell. The positive terminal is where oxidation occurs, which involves the loss of electrons. Therefore, knowing that reduction happens at the cathode and that it is therefore negatively charged helps clarify the overall operation of an electrolytic cell.

In summary, the correct identification of the cathode as the negative electrode where reduction occurs is fundamental to understanding the principles of electrolysis and the functions of different electrodes in various electrochemical cells.