Hello chemistry enthusiasts,
I study physical engineering and as one of the physics internship experiments I have conducted an electrolysis experiment which aimed to find the electrochemical equivalent of copper.
I have written a report on it and for this particular experiment, relative error was 3,74% which is in my eyes pretty satisfactory.
To give some background on the experiment, as electrodes copper rods were used and copper sulfate was placed in an aqueous solution. 3 trials were conducted, each with increasing current (200 300 500 [mA]) and I weighed the liberated mass of material on the cathode, calculated the relevant statistical values such as standard deviation, absolute deviation, standard error, relative error etc. In the discussion part I was to comment on the outcome of this experiment as well as evaluate the error analysis, in which I felt like I did a poor job.
Thankfully I passed, but I am curious so I wanted to ask you what could, other than the weighing error (including the part where you rinse the rods as well), could cause the error in this experiment? Some error related to the energy source perhaps? Or in a more chemical way could something in the solution could lead to this?
Thank you in advance and have a great day.