Microscale chemistry with a coin and a can
Mahmoud K. El-Marsafy, Peter Schwarz

5. Spontaneous electron transfer from Cu to Cl2 in  a Galvanic Cell

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 Photos 5.1 - 5.3
Potential and current between Cu und Cl2 in a blister (1, 2), bead models (3)

After finishing the electrolysis of the  copper salt / table salt solution in experiment 4 the battery is removed and the electrodes are connected to a digital multimeter. It reads a pontial of 1.10 V (1 )and a current of 1969 µA (2).  Bead models (3)  illustrate the electrochemical and electrical steps of this spontaneous indirect electron transfer from Cu to Cl2.
                         Reduction:    Cl2(g)   + 2e-  --> 2 Cl-(aq)
                         Oxidation:            Cu(s)       --> Cu2+(aq) + 2e-
               Redox reaction:   Cu(s) + Cl2 (g)   --> Cu2+(aq) +   2 Cl-(aq)

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