Which of the following best defines corrosion?

Corrosion is best defined as the chemical deterioration of a material, particularly metals, due to reactions with their environment. This process typically involves the material undergoing various chemical transformations when exposed to elements such as moisture, air, or other corrosive substances. For instance, rusting of iron is a well-known example of corrosion where iron reacts with oxygen and moisture to form iron oxide.

Understanding that corrosion is fundamentally a chemical process emphasizes the importance of chemical properties and environmental interactions in determining the longevity and integrity of materials. In contrast, physical wear refers to damage resulting from mechanical actions such as friction or impact, while thermal expansion involves changes in material dimensions due to temperature variations. Electrical breakdown pertains to the failure of materials as a result of electrical stress, which is unrelated to the gradual chemical degradation characterized by corrosion.