How do sacrificial metals protect the less reactive metal that it protects? Some people say that it provides the iron with electrons when it starts to rust. But if it does provide electron to the iron then the magnesium block for example will become positive ions. But then how can the magnesium block exist as a block of positive ions? Similarly how does galvanisation work since they have the same principles. In the air, there are no anions that can form an ionic compound with the magnesium ions. Do electrons from the more reactive metal even give up electrons to the less reactive metal it is attached to or is there another process that I'm not seeing. Thanks for the help!