HandsOn 13 - Growing a Pattern in the Laboratory

I. Introduction

II. Setting Up the Experiment

III. Doing the Experiment

IV. Data Analysis

Setting Up the Experiment

1. Bend the the 1 mm wire into a right-angle about two centimeters from the end and insert it from below through the center hole in the bottom plate. From the center, this wire runs under the lower plate to the edge where it can be clipped to one lead from the power supply.


2. Place the lower plate on its rubber feet on a horizontal surface near the power supply, with the center wire sticking up.


3. Sandpaper the insulation from the thinner copper wire and bend it into a circle between 2 and 4 centimeters in diameter. Leave a small gap between the beginning and end of the circle, so the wire will not cross itself.


4. Lay the circular wire on the lower plate centered on the hole in the plate. Adjust the wire until it lies flat on the plate.


5. Pour the electrolytic liquid onto the center of the plate so that it spreads out to fill the wire circle. Be sure that there are no bubbles in the liquid.


6. Place the upper plate over the lower so that the vertical central wire passes through the holes in both plates. The upper plate should rest on the circular wire. There should be no bubbles in the space between the two wires (electrodes). Clamp each side with a 1/2 inch capacity binder clamp.


7. Now clip the power supply leads to the loose ends of the electrode wires. The negative terminal attaches to the center electrode.


8. Place a sheet of paper under the plates so you can see the pattern as it grows during the experiment.