Which statement accurately summarizes the use of sacrificial anodes in cathodic protection?

Sacrificial anodes are an essential component in cathodic protection systems, primarily because they are designed to protect metal surfaces from corrosion. In this process, the sacrificial anode is made from a more reactive metal than the metal it is protecting, often zinc, magnesium, or aluminum. When these anodes are connected to the metal structure (such as a ship hull or pipeline), they corrode preferentially instead of the protected metal, thereby acting as a protective layer against corrosion.

When the anode begins to corrode, it releases electrons which travel through the electrolyte (such as water or soil) to the protected metal surface. This flow of electrons mitigates the electrochemical reactions that cause the corrosion of the metal, ultimately preventing damage and extending the life of the structure.

While sacrificial anodes do assist in enhancing the longevity of coatings and can contribute indirectly to the aesthetic quality by preventing corrosion damage, their primary function is to serve as the sacrificial layer that prevents the underlying metal from deteriorating. The statement encapsulates this fundamental role well, emphasizing their importance in corrosion protection strategies.