During the process, Mg(OH)2 crystals form on the cathode, causing the current flow to be impeded over time. After each hour of testing and sample removal, the other cathode electrode was added to the beaker, and the negative electricity clip moved to the new electrode. The original electrode was transferred to the test tube labeled "HCl," where it was allowed to sit until all the Mg(OH)2 crystals were decomposed by the HCl. Then the electrode was rinsed off thoroughly to prevent contamination and set aside until the next hour test and solution retrieval.
31ml of 12% H2O2 solution was added to the CuSO4 Synthesis flask for every 20 ml of H2SO4 solution added. The volume needed was derived using the stoichiometric requirements using an average of 6.5M H2SO4 solution from table 4, then adding 10% to account for H2O2 decomposition. For the first two runs, the amount of H2O2 was calculated using equation 5, with the H2O2 Molar mass and density being 34.0147g/mol and 1.45g/ml, respectively. The variable cB represents the measured molar concentration of the sample solution in mol/liter.
(5) \(c_B\times1.10\times0.02_L\times H_2O_{2\left(molar\ mass\right)}\div H_2O_{2\left(density\right)}\div0.12=H_2O_{2\ mL}\)
Equation 5 was simplified to equation six since only cB (representing the tested solution concentration) is variable.
(6) \(c_B\times4.3=H_2O_{2\left(volume\right)}\)
When the CuSO4 synthesis flask was full, it was allowed to stand overnight to ensure thorough H2O2 decomposition. It was then emptied through a filter to ensure small particles of copper wire did not contaminate the CuSO4 solution. The CuSO4 solution was then transferred to an evaporation dish on a hot plate for drying. The solution was dried into a light blue powder and stored in a glass bottle.

2.4 MgSO4 Recycling

Each run was ended when the fluid on the outside of the PVC pipe became too milky and contaminated with Mg(OH)2. The lab power supply current draw which would reach 0.80A during the beginning of the run would start to struggle to reach 0.65A. After each run, the PVC pipe was removed and the filter paper flushed with distilled H2O. The remaining contents in the beaker were stirred with a glass stirrer. The sides of the beaker were scraped as well. The milky contents were then vacuum filtered through a 10-micron filter paper. The result was a clear liquid that could be used for future runs.