iron is coated with zinc even zinc is more reactive than iron why?

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This is the introduction to the article...

Yes, iron is often coated with zinc in a process called galvanization, even though zinc is more reactive than iron. This might seem counterintuitive at first, but the reason behind this lies in the properties of the zinc coating and the way it interacts with iron in certain environments.

This is the introduction to the article...

Zinc is more reactive than iron in the sense that it readily undergoes a process called galvanic corrosion. This occurs when two different metals are in contact in the presence of an electrolyte (such as water with dissolved ions) and a conductive path, like when iron and zinc are in contact. In this setup, the more reactive metal (zinc) can act as a sacrificial anode, corroding preferentially to protect the less reactive metal (iron). When iron is coated with a layer of zinc through a process called hot-dip galvanizing, a protective layer of zinc is formed on the iron's surface. This zinc layer acts as a barrier that shields the underlying iron from direct contact with the environment, preventing the iron from corroding. If the zinc coating is damaged and exposes the underlying iron, the zinc will corrode sacrificially to protect the iron. This method of coating iron with zinc is widely used in various industries to protect iron and steel structures from corrosion, especially in applications where these materials are exposed to harsh environments or moisture. The zinc coating provides an effective and relatively inexpensive way to extend the lifespan of iron and steel products. This principle is the basis for galvanized steel used in construction, automotive manufacturing, and many other industries.