Cool Science: Restore Silver with Electrochemistry

Uploaded by NurdRage on 05.02.2009

Hello fellow Nerds.
In this video we'll be electrochemically restoring these tarnished silver bars.
We'll show you two ways of doing this.
One using aluminum foil,
the other using a battery.
For the aluminum foil method,
get a shallow tray with a piece of aluminum foil much larger than your silver.
Add a solution of salt and baking soda to cover both pieces.
Now when we add it,
as long as the silver does not touch the aluminum,
nothing will happen!
Because we need an electrical connection between the them.
The tarnish is only removed when it directly receives electrons from the aluminum.
So to get it to work,
we simply place the silver on the aluminum to make a connection.
As you can see, the results are very quick and quite dramatic.
We did not time lapse the restoration process.
What you saw actually happened that fast.
Let's try that again with another piece of tarnished silver.
This one is going slower because of the very thick layer of tarnish.
As you can see,
you need the solution of baking soda to touch all parts of the silver in order to restore it.
Now let's try this experiment again with a piece of copper instead of a piece of aluminum foil.
Aluminum gives electrons very easily but copper does not,
so let's see what happens.
As you can see,
nothing will happen because the copper won't easily give its electrons to silver.
However, we can force the electron flow using a battery.
To do this, we simply connect the copper to the positive end of the battery
and then connect the negative end to the silver.
This setup will use the energy of the battery
to force electrons from the copper into the silver.
This is quite dramatic so watch carefully.
Did you miss it? Let me show you again
As long as you have a battery,
this process will occur with any electrode, not just copper.
So there you have it, we've restored tarnished silver with both aluminum and a battery.
Thanks for watching another NurdRage original video.
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