Concept:Galvanization is a specific industrial process designed to protect iron and steel from rusting by providing both a physical barrier and cathodic protection.
Solution:- In galvanization, iron is coated with a thin layer of Zinc.
- Because Zinc has a lower (more negative) standard reduction potential than Iron, it acts as a more reactive, stronger reducing agent.
- If the coating is scratched, the Zinc acts as a "sacrificial anode," corroding preferentially and supplying electrons to the Iron, thus completely preventing the Iron from oxidizing (rusting).
Why other options are incorrect:Coating with Tin is called tin-plating, not galvanizing. Tin is less reactive than Iron, so if a tin coat is scratched, the Iron corrodes even faster. Copper and Aluminum are not used for this specific cathodic protection technique.
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