Question

What is the advantage of galvanized iron over tin-plated iron?

Answer 1

Advantage of galvanised iron over tin-plated iron is that galvanised iron does not rust even if there is scratch on the coating of zinc layer on iron surface. This is because zinc is more reactive than iron and reacts with air to form a sacrificial layer of zinc carbonate, which provides protection against corrosion of iron. In case of tin-plated iron, it easily begins to rust at the place where there is scratch on the tin-plated layer. This is because iron is more reactive than tin and it undergoes oxidation in preference to tin.