- Anonymous2 decades agoFavorite Answer
There are two kinds of zinc/copper couples
1. Simple cell
Dip the two metals in copper (II) sulphate solution(or other electrolyte).
Use a connecting wire to connect the two metals .
As Zinc is higher than Copper in the electrochemical series, zinc loses electrons
more readily than copper and electrons will flow from zinc to copper through the
Ionic half equation(Use Copper (II) sulphate as electrolyte:
at zinc electrode: Zn→Zn2+ + 2e
at copper electrode: Cu2+ +2e →Cu(because Cu2+ lower than H+ in electrolyte)
Disadvantage: When zinc is dipped into copper (II) sulphate solution, there is direct
electrons transfer from zinc to copper ions in the electrolyte.
As a result, zinc dissolves rapidly and fewer electrons will flow
through the external circuit.
2.Simple cell with salt bridge
As mensioned by the person above.
Advantage: No displacement reaction occurs.
Disadvantage: Electrolyte soaked in salt bridge may dry out.
Pay attention: The electrolyte soaked in salt bridge should have no reaction with the
solution in the two half cells.Source(s): My brain
- 1 decade ago
- 2 decades ago