That’s right we are flexing our brain muscles in today’s post. My oldest received a potato clock kit for his birthday… and was dying to do it… in fairness I had been using it as a reward to get homework done, room cleaned, world peace achieved, etc… for at least two weeks… so it was definitely time to pay up… I won’t lie it sounded fun to me too. As we were setting everything up it occurred to me that there was no reason not to share this with everyone else… So mentally I went through my Mr. Rogers routine… grabbed my iPod touch… and made you all a video. Check the video and the explanation of the experiment out below:
So here is what happened this whole thing is a redox reaction (Oxidation/Reduction Reaction), the potatoes function as electrolytes transferring electrons through the wire to the clock and back to the other potato, completing a circuit.
There are two of each metal strips (electrodes)
- The zinc strips are the anodes
- The copper strips are the cathodes.
The zinc reacts with the zinc in the potatoes, which creates extra electrons this is the oxidation part of this circuit which happens as the zinc loses it’s electrons.
Now the copper is collecting of zinc’s excess electrons which is the reduction part of the circuit.
So what is happening is the copper obtains the loose electrons and creates more copper from them. Basically while the zinc depletes itself, the copper is continues to coat itself with layers of new copper.
There is about a half a volt created in this reaction plenty to power a little LCD clock… as a side note… our clock is still running… almost 3 weeks later!