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In our last post: Electrolysis of Some Typical Electrolytes (Part I) , we studied the electrolysis of acidified water, dilute sodium chloride and brine under different conditions. Here, we will be looking at the electrolysis of copper (II) tetraoxosulphate (VI), CuSO4, solution. In solution, copper (II) tetraoxosulphate (VI) undergoes complete ionization to form copper (II) ions, Cu2+, and tetraoxosulphate (VI) ions, SO4--, according to the equation:                                          CuSO4(aq) ----> Cu2+(aq) + SO4--(aq) .....................(i) Note that the two minus signs attached to the SO4 stand for 2- Electrolysis of Dilute Copper (II) tetraoxosulphate (VI) Using Inert (Platinum or Carbon) Electrodes The ions present in copper (II) tetraoxosulphate (VI) solution are Cu2+, SO4-- and H+, OH-; with the latter pair coming from the dissociation of water. Expectedly, the OH- and SO4-- ions migrate to the anode, while the H+ and Cu2+ ions migrate to the cathode. 

Electrolysis is a word formed from two Latin words - 'electrum', which means electricity and 'lysis', which means to breakdown. Therefore, electrolysis is defined as the use electrical energy to breakdown a compound into its constituent elements. For instance, using electricity to decompose sodium chloride into sodium metal and chlorine gas, as depicted by their state symbols (s) and (g) in the equation below:                       2NaCl(aq) ----> 2Na(s) + Cl2(g) It is a redox process, and one needs a good understanding of redox reactions to understand it. (Kindly refer to our posts on Redox Reactions: Overview ,   Balancing Redox Equations and Oxidation Numbers ) Before we continue, it is imperative to understand the meanings of some terminologies in electrolysis. Definition of Terms Electrolyte This is a substance which conducts electricity in the aqueous or molten state and gets decomposed in the process. An aqueous solution is formed when a substanc