Process of Coating of iron with zinc to protect it from rusting is known as ______.

Galvanization

The correct answer is option 3. Galvanization.

Galvanization is a process where a layer of zinc is applied to the surface of iron or steel to protect it from corrosion or rusting. This process is named after Luigi Galvani, an Italian scientist.

The galvanization process typically involves dipping the iron or steel object into a bath of molten zinc or applying a zinc coating using an electroplating process. Once the zinc layer is applied, it forms a protective barrier over the iron or steel substrate.

The protective properties of galvanization arise due to the fact that zinc is more reactive than iron. When the coated iron or steel is exposed to moisture or oxygen in the atmosphere, the zinc layer corrodes sacrificially instead of the underlying iron or steel. This sacrificial corrosion helps to prevent rust formation on the iron or steel substrate.

Galvanization is commonly used to protect various iron and steel products such as structural steel beams, fencing, guardrails, nails, screws, and many other items exposed to outdoor or corrosive environments. It provides long-lasting protection against corrosion, extending the lifespan of the coated metal objects.