Procedure :

1. Prepare solution A (0.20 M) by weighing 5 g of CuSO₄·5H₂O and transferring it to a 100 mL volumetric flask, then making up the volume with deionized water.
   
2. Prepare solution B (0.10 M) by weighing 2.5 g of CuSO₄·5H₂O and transferring it to a 100 mL volumetric flask, then making up the volume with deionized water.
   
3. Connect the two beakers using a KCl salt bridge.
   
4. Immerse clean copper electrodes of identical size into each solution.
   
5. Connect the copper electrodes to a voltmeter using crocodile clips.
   
6. The electrode in 0.20 M CuSO₄ solution was connected to the positive terminal, while the electrode in 0.10 M CuSO₄ solution was connected to the negative terminal of the voltmeter.
   
7. Record the cell voltage and observe its decrease with time until equilibrium is reached.
   
8. Add Na₂S solution to the higher concentration solution to reduce Cu²⁺ concentration and observe the reversal of the cell voltage.