Chemicals and Solutions:
1 Molar Copper Sulfate solution
10 millimolar Copper Sulfate solution
Two copper strips, each in a metal holder
Two 400 mL beakers
Fill one beaker half full with 1M copper sulfate solution and place one of the copper strips in the solution. Fill the other beaker half full with a 10 millimolar solution of copper sulfate and place another copper strip in this solution. Connect the copper strips to the digital voltmeter and then complete the circuit by inserting a salt bridge.
The potential of a concentration cell is given by the Nerst equation:
The 1 millimolar compartment is the anode:
Cu (s) ---> Cu2+(aq) + 2e-
and the 1 M compartment is the cathode
Cu2+(aq) + 2e- ---> Cu (s)
For a concentration cell Eo is zero because both compartments are identical. For the copper concentration cell, the number of electrons tranferred per copper atom is 2, so n=2.