Final answer:
Operational methods to control corrosion include applying protective coatings, using cathodic protection with sacrificial anodes, and the formation of protective oxide films on metal surfaces.
Step-by-step explanation:
Corrosion is the deterioration of metals through a redox process, predominantly oxidation. This process is both chemically and economically significant due to the extensive damage and cost of replacement for corroded materials. To control corrosion, several operational methods are employed:
- Protective Coatings: Applying a layer of a metal that oxidizes less readily than the protected metal, or a more reactive metal for cathodic protection, can help prevent corrosion. For example, galvanized steel has a thin layer of zinc that protects the underlying steel from oxidation.
- Cathodic Protection: This method involves the use of sacrificial anodes, which are typically blocks of zinc attached to the metal being protected. The sacrificial anode corrodes in place of the protected metal, such as the steel hull of a ship.
- Formation of a protective oxide film: Some metals, like aluminum and stainless steels, form a protective oxide layer that shields the metal from further corrosion. In addition to the oxide layer, aluminum cans have a thin plastic layer to prevent contact with acids.
Each method works by providing a barrier or offering a sacrificial material to safeguard the integrity of the metal in question, reducing the rate or possibility of corrosion and thereby extending the life of the metal product.