Preparing the metal strips

Use a small piece of sand paper to clean the metal until the surface is clean and shiny. Wipe the metal with a laboratory tissue to remove any dirt or small metal slivers clinging to the surface. Finally, firmly clamp the metal that will be reduced into the alligator clip on the red lead and the metal that will be oxidized to the alligator clip on the black lead.

If you are unsure which metal will be oxidized and which will be reduced, simply clamp one of the metals into each of the alligator clips. Be sure to record the color of the alligator clip into which each metal was clamped.