Question
Thu September 08, 2011 By: Srikar T

If zinc is higher than iron in the reactivity series, how does galvanization prevent the rusting of iron, when in theory, zinc should react with the gases in air?

Expert Reply
Thu September 08, 2011

The 'rusting' or corrosion can be prevented by connecting iron to a more reactive metal (e.g. zinc or magnesium). This is referred to as sacrificial protection or sacrificial corrosion, because the more reactive protecting metal is preferentially oxidised away, leaving the protected metal intact.

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