Electrolysis Reactions

[andie]

Hey!

I am doing an experiment of electrolysis with initially a copper strip attached to the negative terminal of a battery. A strip of aluminium is then attached to the positive terminal and both electrodes are placed in a copper sulfate solution. My observations are only that oxygen gas is formed on the aluminium electrode while in the solution, but no real reaction occurs.

 

When i switch the copper strip to the positive terminal and the aluminium strip to the negative terminal I see that copper has been deposited on the aluminium.

 

What are the reactions for these two options????

[bob000555]

When you do the first electrolysis your anode is being “eaten”(oxidized actually) and turned into copper hydroxide. In the seconded reaction you are electroplating copper from the CuSO4 on the aluminum.