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Electrochemistry

You can actually do exercises in electrolysis, electroplating, making voltaic cells and determining the reduction series of elements. The key word is 'actually' because usually scientific equipment is so expensive that experiments are at best only demonstrated at the front of a class. This series introduces you to extremely inexpensive, yet safe, equipment that is readily available. It is hard to beat a VOLTAIC CELL made from some fruit or vegetable! The set up is simple (shown to the left of the title, above. What is more as is shown, with a few added metals, the reduction potential series can be easily determined.
Show me how to make a fruit or vegetable battery !

The plastic drinking cup ELECTROLYSIS device shown at the right is rather self-explanatory, and can be easily made at home. The parts are obtained from RadioShack, grommets from a hardware store, graphite electrodes are extracted from large first-grader pencils. Interesting questions arise when the students do NOT obtain the result of two hydrogens to one oxygen. If the salt is adjusted to more or less concentrated, or away from the halides, more chemistry sneaks in to help answer the puzzled minds of the students.
I want to try my hand at doing electrolysis!

Electroplating is an interesting switch because ordinarily things would go the opposite direction as with the fruit voltaic cell in the first part above. But if we impose an opposite voltage that exceeds that of the voltaic cell, the reaction is driven in the opposite direction - often with the result that a metal is plated out on the negative electrode. Of course, out of sight, this is happening in your rechargable automotive battery when it is charging as lead metal is plating out from the PbSO₂ electrolyte. In practice, often the metal forms as needles that don't adhere well to the electrode and fall to the bottom of the container. So it happens in the figure shown to the left when you try to plate out copper from the colored solution. The copper appears black(!) as it clings to the electrode and bits fall to the bottom. BUT collect some of it and remove it from the solution and - voilà! - it is recognizably golden in color!
See: I want to see if I can make some copper!

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