Question

It requires substantial energy to reduce metal ore to pure metal. The reverse process, corrosion, happens spontaneously. The rusting of iron, the tarnishing of silver, and the formation of patina on copper and brass are some common examples of corrosion.

Rusting is the greatest corrosion problem because it occurs rapidly and because so many objects are made of iron and steel. A great deal of the annual production of iron goes simply to replace that lost by rusting. Iron will not rust in dry air or in water that is completely free of air. Oxygen gas and water must be present for iron to rust. Describe chemistry and electrochemistry of corrosion of iron and copper. In each redox reaction, specify the element that is being oxidized, the element that is being reduced, and identify the oxidizing and the reducing agent. Why cars rust more rapidly near the beach or in cold climate where salt is used to de-ice the roads?