Slide Projector Corrosion Cell

The corrosion of metals, especially iron, is a serious problem that costs billions of dollars every year. The process of corrosion can be demonstrated in a slide projector, since the cell is in the shape of a slide, or on the stage of an overhead projector by setting up a simple galvanic cell.Corrosion occurs as the result of a galvanic cell reaction, in which the corroding metal acts as the anode.Several simple demonstrations relating to corrosion are described here, for example : differential aeration cell, differential temperature cell, stress–corrosion cracking, and cathodic protection. We have found this kind of presentation to be very successful. Even in a large lecture room, the demonstration can be easily seen by all of the students.