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How can I show that changing certain variables affects the electroplating process

I am working with my son on a simple electroplating science experiment. I would appreciate your advice on how to introduce a variable or two into the experiment. We will electroplate using copper pennies as the cathode and zinc for the anode in a solution of water based zinc salt.

I would like to show how changing the temperature of the water solution (electrolyte) or some other variables affects the amount or rate of electroplating. What variable would you propose to show how different conditions alter the electroplating process? I would like to keep the experiment simple and be able to easily measure the variables that change -- such as a water temperature change using a thermometer. Thanks in advance for your suggestions.

Rich Merski
student - Vienna, Virginia
2004

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2004

In a nutshell, you have to keep everything constant except the variable you want to change. For example, if you want to isolate the effect of temperature, you have to keep the anode and cathode the same along with the make up of the electrolyte, electrical current, anode/cathode spacing, plating geometry, and time. Doing that, you can try a couple of different temperatures.

The real way to do this sort of thing is to use a statistical experiment design (Taguchi, Box-Bencken, etc.) with the appropriate data analysis (analysis of variance). However, I think that this sort of thing is beyond your scope.

James Totter, CEF
- Tallahassee, Florida

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It would help if we knew what age your child is and what equipment you may have. It is easy to design an experiment for a chemistry research laboratory, but it would be impossible to do that experiment in the kitchen sink! Initially I would suggest something along the lines of copper plating, so you will need a controllable power supply, ammeter and voltmeter, chemicals and suitable containers. Let us know what you have available and what age group it is being aimed at.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2004

A good solid regulated power source is a computer power supply, they have two leads one running off at 12v and another at 5v (if I remeber correctly, check on the enclosure). Anywho, the voltage is constant, and reletivly low (lower ampres as well), if the wires cross it will not short out your house, trip a breaker, or blow a fuse. I will just shut the supply down. Hope that helps some.

Marc Banks
- Elizabeth City, North Carolina
2004

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2004

The following are the deposition parameters
1) pH of the solution
2) temperature
3) potential difference
4) Dist between the electrodes
5) concentration of the solute. Keep 0ne varying by keeping the others constant.

Chandramohan Rathinam
SSA college - Devakottai, Tamil Nadu, India