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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: Walkier on October 13, 2014, 12:23:38 AM

Title: Does temperature affect electrolysis of CuSO4 to make copper?
Post by: Walkier on October 13, 2014, 12:23:38 AM

I'm currently in grade 10 and I'm doing a lab where we are investigating the effect of temperature electrolysis of CuSO4 to make copper. The data we got was inconclusive. However, I still need to explain what would actually happen and reasons behind it in the conclusion. After some research, I found some sources that it has should no effect but some says it does affect certain reactions. I also asked my teacher and even though he has a brief answer, he still remains skeptical.  All out all the sources, none of them seemed really convincing or reliable so I'm really confused right now.

So does temperature affect electrolysis of CuSO4 to make copper?

Title: Re: Does temperature affect electrolysis of CuSO4 to make copper?
Post by: Hunter2 on October 13, 2014, 01:23:11 AM

Temperature has an effect on the quality of the plated copper. Higher temperature accelerate chemical reaction, so the deposit is very rough and non ductile.

Title: Re: Does temperature affect electrolysis of CuSO4 to make copper?
Post by: Borek on October 13, 2014, 03:18:53 AM

No idea what was the investigation you did, so it is hard to comment on.

In general - things definitely change with temperature. If the changes are small, they can be masked by the experimental errors. My bet is that is the case here.

Of things that definitely change - see the Nernst equation, it has a temperature dependent term. Changes are small, and in the controlled current experiments completely irrelevant - but they do exist.

Title: Re: Does temperature affect electrolysis of CuSO4 to make copper?
Post by: Arkcon on October 13, 2014, 05:21:19 AM

Usually, these sorts of questions, "What is wrong with my experiment" tend to go nowhere on this board.  This time, you've gotten good answers.  Use the Nernst equation, plugging in your various temperatures, and see how your measured parameter (what was that, I can't tell) could theoretically change.  If that change is less than you can measure, that should satisfy your instructor.  Note that in the formula:  http://en.wikipedia.org/wiki/Nernst_equation#Expression  temperature is in the numerator, multiplied by a power function.  You should be able to see an effect, but how much of one will depend on how much temperature difference there was, and what you're able to measure.