What happens at the anode and cathode during electrolysis?

During electrolysis, oxidation occurs at the anode and reduction occurs at the cathode.

In more detail, electrolysis is a process that uses an electric current to drive a non-spontaneous chemical reaction. This process takes place in an electrolytic cell, which consists of two electrodes: an anode and a cathode, submerged in an electrolyte.

At the anode, which is the positive electrode, oxidation occurs. Oxidation is a process where a substance loses electrons. In the context of electrolysis, the substance could be an ion in the electrolyte or an atom of the electrode itself. For example, if the electrolyte is a solution of copper sulfate, the copper ions (Cu2+) in the solution will be attracted to the anode. Here, they lose two electrons to become copper atoms, which are then deposited on the anode.

On the other hand, at the cathode, which is the negative electrode, reduction takes place. Reduction is a process where a substance gains electrons. Again, the substance could be an ion in the electrolyte or an atom of the electrode. Using the same example of a copper sulfate solution, the sulfate ions (SO4 2-) are attracted to the cathode. Here, they gain two electrons to become sulfate atoms. However, in most cases, it's the water that gets reduced at the cathode, producing hydrogen gas and hydroxide ions.

In summary, the anode and cathode play crucial roles in electrolysis. The anode is where oxidation takes place, involving the loss of electrons. The cathode is where reduction occurs, involving the gain of electrons. Understanding these processes is key to understanding electrolysis and its applications in various fields, from industry to everyday life.