Correct Answer - Option 4 : Zinc plating
Galvanization: In the process of Galvanization, Zinc is coated over iron. zinc coating is the best and durable method for protection of iron.
- When iron comes in contact with air and moisture, rust forms over it and eats away the metal.
- Rust is hydrated iron oxide with the chemical formula Fe2O3. nH2O.
- Zinc is coated over iron to protect the latter from rusting.
- The most common way of galvanizing iron is dipping it in the hot molten zinc.
- When Zinc gets coated over the iron it protects iron from coming in contact with air and moisture.
Hence, we can conclude that The most durable metal plating on iron to protect against corrosion is Zinc plating.
- Nickel electroplating is a technique of electroplating a thin layer of nickel onto a copper object.
- Copper plating: copper is commonly used as an underplating for silver, gold,
- Tin plating: Tin is extremely cost-effective and is commonly applied to a preliminary coating of copper.